New JoinVarArgsContains inspection that will detect multiple .contains(), .doesNotContain(), and .containsOnlyOnce() calls within the same statement that could be joined together using variadic arguments.

Unrelated: Upgraded Gradle to 5.4.1. Upgraded kotlin to 1.3.40. Upgraded jacoco to 0.8.4. Minor style change for immediate returns. Increased test/branch coverage.

README.md

@@ -79,12 +79,35 @@ You can toggle the various inspections in the Settings/Editor/Inspections in the
   ```
   from: assertThat(expected).someCondition();
         assertThat(expected).anotherCondition();
-    to: assertThat(expected).someCondition().anotherCondition();
+    to: assertThat(expected).someCondition()
+                            .anotherCondition();
   ```
-  Joining will work on actual expressions inside assertThat() that are equivalent expressions,
-  except for method calls with known side-effect methods such as ```Iterator.next()``` -- please notify me about others.
+  Joining will work on actual expressions inside ```assertThat()``` that are equivalent expressions,
+  except for method calls with known side-effect methods such as ```Iterator.next()``` and
+  pre/post-increment/decrement operations -- please notify me about others.
 
-  The comments of the statements will be preserved. When using ```.extracting()``` or similar, the statements will not be merged.
+  The comments of the statements will be preserved. When using ```extracting()``` or similar,
+  the statements will not be merged.
+  
+  The behavior regarding the insertion of line breaks between the expressions can be configured in the
+  inspection settings.
+
+- JoinVarArgsContains
+
+  Looks for ```.contains()```, ```.doesNotContain()```, and .```containsOnlyOnce()``` calls for iterables 
+  within the same statement. The available quickfix can join the arguments to variadic version of the call
+  and remove the surplus one.
+  
+  ```
+  from: assertThat(expected).contains("foo").doesNotContain("bar").contains("etc").doesNotContain("huh");
+    to: assertThat(expected).contains("foo", "etc").doesNotContain("bar", "huh");
+  ```
+  Will not be performed on more complex statements with ```.extracting()``` or ```.as()``` to avoid
+  changing semantics or losing descriptions.
+
+  Note that the quickfix does not handle comments very well and might remove them during the operation.
+  
+  You may need to perform some manual reformatting, if the line gets too long after applying the fix.
 
 - AssertThatObjectIsNullOrNotNull
 
@@ -145,7 +168,7 @@ You can toggle the various inspections in the Settings/Editor/Inspections in the
 
 - AssertThatStringExpression
   
-  Moves string operations inside assertThat() out.
+  Moves string operations inside ```assertThat()``` out.
   
   ```
   from: assertThat(stringActual.isEmpty()).isTrue();
@@ -169,6 +192,46 @@ You can toggle the various inspections in the Settings/Editor/Inspections in the
   ```
   Analogously with ```isFalse()```.
 
+- AssertThatObjectExpression
+
+  Handles equals(), toString() and hashCode() inside an expected expression.
+  
+  ```
+  from: assertThat(objActual.equals(objExpected)).isTrue();
+    to: assertThat(objActual).isEqualTo(objExpected);
+
+  from: assertThat(objActual.toString()).isEqualTo(stringExpected);
+    to: assertThat(objActual).hasToString(stringExpected);
+
+  from: assertThat(objActual.hashCode()).isEqualTo(objExpected.hashCode());
+    to: assertThat(objActual).hasSameHashCodeAs(objExpected);
+  ```
+
+- AssertThatCollectionOrMapExpression
+
+  Moves collection and map operations inside ```assertThat()``` out.
+
+  ```
+  from: assertThat(collection.isEmpty()).isTrue();
+    to: assertThat(collection).isEmpty();
+
+  from: assertThat(collection.contains("foobar")).isTrue();
+    to: assertThat(collection).contains("foobar");
+    
+  from: assertThat(collection.containsAll(otherCollection)).isTrue();
+    to: assertThat(collection).containsAll(otherCollection);
+
+  from: assertThat(map.isEmpty()).isTrue();
+    to: assertThat(map).isEmpty();
+
+  from: assertThat(map.containsKey(key)).isTrue();
+    to: assertThat(map).containsKey(key);
+    
+  from: assertThat(map.containsValue(value)).isTrue();
+    to: assertThat(map).containsValue(value);
+  ```
+  Analogously with ```isFalse()``` (except for ```containsAll()```).
+
 - AssertThatEnumerableIsEmpty
 
   Uses ```isEmpty()``` for ```hasSize(0)``` iterable assertions instead.
@@ -239,22 +302,37 @@ You can toggle the various inspections in the Settings/Editor/Inspections in the
     to: assertThat(primActual).isEqualTo(primExpected);
 
   from: assertThat(10 < primActual).isNotEqualTo(false);
-    to: assertThat(primActual).isGreaterThan(primExpected);
+    to: assertThat(primActual).isGreaterThan(10);
 
   from: assertThat(objActual != objExpected).isEqualTo(true);
     to: assertThat(objActual).isNotSameAs(objExpected);
 
   from: assertThat(null == objActual).isFalse();
     to: assertThat(objActual).isNotNull();
-
-  from: assertThat(objActual.equals(objExpected).isTrue();
-    to: assertThat(objActual).isEqualTo(objExpected);
   ```
   ...and many, many more combinations (more than 150).
 
+- ImplicitAssertion
+
+  Detects and removes implicit use of ```isNotNull()```, ```isNotEmpty()``` and
+  ```isPresent()``` when followed by an assertion that will implicitly cover this
+  check.
+
+  ```
+  from: assertThat(string).isNotNull().startsWith("foo");
+    to: assertThat(string).startsWith("foo");
+
+  from: assertThat(list).isNotEmpty().hasSize(10);
+    to: assertThat(list).hasSize(10);
+
+  from: assertThat(optional).isPresent().contains("foo");
+    to: assertThat(optional).contains("foo");
+  ```
+  ...and many more combinations (more than 100).
+
 - AssertThatJava8Optional
 
-  Examines the statement for Java 8 Optional type and whether the statement
+  Examines the statement for Java 8 ```Optional``` type and whether the statement
   effectively tries to assert the presence, absence or content and then 
   replaces the statement by better assertions.
   
@@ -275,8 +353,14 @@ You can toggle the various inspections in the Settings/Editor/Inspections in the
   from: assertThat(opt.get()).isSameAs("foo");
     to: assertThat(opt).containsSame("foo"); 
 
+  from: assertThat(opt.orElse(null)).isEqualTo(null);
+    to: assertThat(opt).isNotPresent();
+     
+  from: assertThat(opt.orElse(null)).isNotEqualTo(null);
+    to: assertThat(opt).isPresent();
+     
   from: assertThat(opt).isEqualTo(Optional.of("foo"));
-  from: assertThat(opt).isEqualTo(Optional.ofNullable("foo"));
+  from: assertThat(opt).isEqualTo(Optional.ofNullable("foo")); // only for constant "foo"
     to: assertThat(opt).contains("foo"); 
 
   from: assertThat(opt).isEqualTo(Optional.empty());
@@ -288,7 +372,7 @@ You can toggle the various inspections in the Settings/Editor/Inspections in the
 
 - AssertThatGuavaOptional
 
-  Examines the statement for Google Guava Optional type and whether the statement
+  Examines the statement for Google Guava ```Optional``` type and whether the statement
   effectively tries to assert the presence, absence or content and then 
   replaces the statement by better assertions.
 
@@ -306,8 +390,14 @@ You can toggle the various inspections in the Settings/Editor/Inspections in the
   from: assertThat(opt.get()).isEqualTo("foo");
     to: assertThat(opt).contains("foo");
      
+  from: assertThat(opt.orNull()).isEqualTo(null);
+    to: assertThat(opt).isAbsent();
+     
+  from: assertThat(opt.orNull()).isNotEqualTo(null);
+    to: assertThat(opt).isPresent();
+     
   from: assertThat(opt).isEqualTo(Optional.of("foo"));
-  from: assertThat(opt).isEqualTo(Optional.fromNullable("foo"));
+  from: assertThat(opt).isEqualTo(Optional.fromNullable("foo")); // only for constant "foo"
     to: assertThat(opt).contains("foo"); 
 
   from: assertThat(opt).isEqualTo(Optional.absent());
@@ -328,14 +418,17 @@ You can toggle the various inspections in the Settings/Editor/Inspections in the
   as being skipped.
 
   Return statements in ```if``` statements in main test methods (must be annotated with JUnit 4 or 
-  Jupiter @Test annotations) will be verified to have at least one ```assertThat()``` statement in the code flow.
+  Jupiter ```@Test``` annotations) will be verified to have at least one ```assertThat()``` statement in the code flow.
   Method calls within the same class will be examined for ```assertThat()``` statements, too.
   However, at most 50 statements and down to five recursions will be tolerated before giving up.
   
   Currently, the quickfix may lose some comments during operation. The other branch of the ```if``` statement
   will be inlined (blocks with declarations will remain a code block due to variable scope).
+  The quickfix will only work with AssertJ >= 2.9.0 (for 2.x releases) or >= 3.9.0 (for 3.x releases).
   
-  The generated ```assumeThat()``` statement could be optimized further (similar to ```assertThat()```).
+  The generated ```assumeThat()``` statement could be optimized further (similar to ```assertThat()```), but
+  there is currently no support in Cajon for this (you could rename the method to ```assertThat()``` optimize it
+  and turn it back into ```assumeThat()``` in the end).
 
   Example:
   
@@ -361,7 +454,10 @@ You can toggle the various inspections in the Settings/Editor/Inspections in the
 
 - JUnitAssertToAssertJ
 
-  Tries to convert most of the JUnit 4 assertions to AssertJ format.
+  Tries to convert most of the JUnit 4 assertions and assumptions to AssertJ format.
+  Sometimes the expected and actual expressions are specified in wrong order -- 
+  Cajon tries to swap these when it detects the supposed actual expression to be a
+  constant while the expected one is not.
 
   Does not support Hamcrest-Matchers.
   If you need that kind of conversion, you might want to check out the
@@ -374,8 +470,8 @@ You can toggle the various inspections in the Settings/Editor/Inspections in the
   assertFalse(message, condition);
   assertNull(object);
   assertNull(message, object);
-  assertNonNull(object);
-  assertNonNull(message, object);
+  assertNotNull(object);
+  assertNotNull(message, object);
   assertEquals(expected, actual);
   assertEquals(message, expected, actual);
   assertEquals(expectedDoubleOrFloat, actualDoubleOrFloat, delta);
@@ -392,6 +488,14 @@ You can toggle the various inspections in the Settings/Editor/Inspections in the
   assertArrayEquals(message, expectedArray, actualArray);
   assertArrayEquals(expectedDoubleOrFloatArray, actualDoubleOrFloatArray, delta);
   assertArrayEquals(message, expectedDoubleOrFloatArray, actualDoubleOrFloatArray, delta);
+  
+  assumeTrue(condition);
+  assumeTrue(message, condition);
+  assumeFalse(condition);
+  assumeFalse(message, condition);
+  assumeNotNull(object); // single argument only!
+  assumeNoException(throwable);
+  assumeNoException(message, throwable);
   ```
 
 ### Implemented referencing
@@ -410,8 +514,8 @@ You can toggle the various inspections in the Settings/Editor/Inspections in the
   .flatExtracting(Extractors.resultOf("bareMethod")
   ```
   Works on both POJOs and ```Iterable```s/```Array```s. 
-  Implementation is very basic though and does not work with fancy cascaded .extracting() sequences.
-  If there's demand, I will add it.
+  Implementation is very basic though and does not work with fancy cascaded ```.extracting()``` sequences.
+  If there's demand, I could add it.
 
 ## Development notice
 
@@ -419,19 +523,48 @@ Cajon is written in Kotlin 1.3.
 
 Cajon is probably the only plugin that uses JUnit 5 Jupiter for unit testing so far (or at least the only one that I'm aware of ;) ).
 The IntelliJ framework actually uses the JUnit 3 TestCase for plugin testing and it took me quite a while to make it work with JUnit 5.
-Feel free to use the code (in package de.platon42.intellij.jupiter) for your projects (with attribution).
+Feel free to use the code (in package ```de.platon42.intellij.jupiter```) for your projects (with attribution).
 
 ## Planned features
+- More Optional fixes such as opt1.get() == opt2.get() etc.
+- Converting ```foo.compareTo(bar) == 0``` to ```isEqualTo()``` (yes, I've *really* seen code like that)
 - Extraction with property names to lambda with Java 8
+
   ```
   from: assertThat(object).extracting("propOne", "propNoGetter", "propTwo.innerProp")...
     to: assertThat(object).extracting(type::getPropOne, it -> it.propNoGetter, it -> it.getPropTwo().getInnerProp())...
   ```
 
-- Kotlin support (right now, however, with less than 100 downloads after a month, this is unlikely to happen)
-
 ## Changelog
 
+#### V1.3 (03-Aug-19)
+- New JoinVarArgsContains inspection that will detect multiple ```.contains()```, ```.doesNotContain()```,
+  and ```.containsOnlyOnce()``` calls within the same statement that could be joined together using variadic arguments.
+- AssertJ 3.13.0 broke some inspections due to new ```AbstractStringAssert::isEqualTo()``` method.
+- AssertThatJava8Optional and AssertThatGuavaOptional inspections do not longer try to fix
+  ```assertThat(optional).isEqualTo(Optional.fromNullable(expression))``` to ```contains()```
+  when ```expression``` is not a non-null constant expression.
+  
+#### V1.2 (23-Jun-19)
+- Due to popular demand the JoinAssertThatStatements inspection will now add line breaks on joining statements.
+  The amount of statements joined without causing line breaks can be configured but defaults to 1 (always).
+          
+#### V1.1 (09-Jun-19)
+- Improved JoinAssertThatStatements detection of expressions with side-effects and added pre/post-increment/decrement detection.
+- Added Guava Optional ```opt.orNull() == null``` case. You know, I'm not making this stuff up, people actually write this kind of code.
+- Added Java 8 Optional ```opt.orElse(null) == null``` case, too.
+- Extended JUnitAssertToAssertJ inspection to convert JUnit ```assume``` statements, too.
+- Improved JUnitAssertToAssertJ quick fix to swap expected and actual expressions if the actual one is a constant.
+- New ImplicitAssertion inspection for implicit ```isNotNull()```, ```isNotEmpty()``` and ```isPresent()``` assertions that will be covered by chained assertions.
+- Fix for multiple JUnit Conversions in batch mode with and without delta creating an exception.
+- Added new AssertThatObjectExpression inspection for ```toString()``` and ```hashCode()``` and moved ```equals()``` from AssertThatBinaryExpression there.
+
+#### V1.0 (06-May-19)
+- First release to be considered stable enough for production use.
+- Fixed a NPE in AssumeThatInsteadOfReturn inspection quickfix for empty else branches.
+- Fixed missing description for AssumeThatInsteadOfReturn inspection.
+- Added new AssertThatCollectionOrMapExpression inspection that tries to pull out methods such as ```isEmpty()``` or ```contains()``` out of an actual ```assertThat()``` expression.
+
 #### V0.8 (05-May-19)
 - Fixed missing description for JoinAssertThatStatements and detection of equivalent expressions (sorry, released it too hastily).
 - Fixed ```isEmpty()``` for enumerables and strings and ```isNull()``` for object conversions to be applied only if it is the terminal method call as ```isEmpty()``` and ```isNull()``` return void.

build.gradle

@@ -1,13 +1,13 @@
 plugins {
     id 'java'
-    id 'org.jetbrains.intellij' version '0.4.8'
-    id 'org.jetbrains.kotlin.jvm' version '1.3.31'
+    id 'org.jetbrains.intellij' version '0.4.9'
+    id 'org.jetbrains.kotlin.jvm' version '1.3.41'
     id 'jacoco'
-    id 'com.github.kt3k.coveralls' version '2.8.2'
+    id 'com.github.kt3k.coveralls' version '2.8.4'
 }
 
 group 'de.platon42'
-version '0.8'
+version '1.3'
 
 repositories {
     mavenCentral()
@@ -20,10 +20,10 @@ repositories {
 
 dependencies {
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
-    testCompile "org.assertj:assertj-core:3.12.2"
+    testCompile "org.assertj:assertj-core:3.13.0"
     testCompile "org.assertj:assertj-guava:3.2.1"
-    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.4.0'
-    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.4.0'
+    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.5.1'
+    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.5.1'
     testImplementation "org.jetbrains.kotlin:kotlin-test"
 //    testImplementation "org.jetbrains.kotlin:kotlin-test-junit"
 }
@@ -35,31 +35,22 @@ compileTestKotlin {
     kotlinOptions.jvmTarget = "1.8"
 }
 intellij {
-    version '2019.1.1'
+    version '2019.2'
 //    pluginName 'Concise AssertJ Optimizing Nitpicker (Cajon)'
     updateSinceUntilBuild false
+    plugins = ['java']
 }
 
 patchPluginXml {
     changeNotes """
-  <h4>V0.8 (05-May-19)</h4>
+  <h4>V1.3 (03-Aug-19)</h4>
     <ul>
-      <li>Fixed missing description for JoinAssertThatStatements and detection of equivalent expressions (sorry, released it too hastily).
-      <li>Fixed isEmpty() for enumerables and strings and isNull() for object conversions to be applied only if it is the terminal method call as isEmpty() and isNull() return void.
-      <li>Heavily reworked inspections for edge cases, such as multiple isEqualTo() calls inside a single statement.
-      <li>Some inspections could generate bogus code for weird situations, this has been made more fool-proof.
-      <li>Corrected highlighting for many inspections.
-      <li>Fixed family names for inspections in batch mode.
-      <li>Reworded many inspection messages for better understanding.
-      <li>Added a first version of a new inspection that tries to detect bogus uses of return statements in test methods and replaces them by assumeThat() calls.
-    </ul>
-  <h4>V0.7 (28-Apr-19)</h4>
-    <ul>
-      <li>Another fix for AssertThatGuavaOptional inspection regarding using the same family name for slightly different quick fix executions
-          (really, Jetbrains, this sucks for no reason).
-      <li>Extended AssertThatSize inspection to transform hasSize() into hasSameSizeAs(), if possible.
-      <li>Implemented first version of JoinAssertThatStatements inspection that will try to merge assertThat() statements with the same
-          actual object together, preserving comments.
+      <li>New JoinVarArgsContains inspection that will detect multiple .contains(), .doesNotContain(), and .containsOnlyOnce()
+          calls within the same statement that could be joined together using variadic arguments.
+      <li>AssertJ 3.13.0 broke some inspections due to new AbstractStringAssert::isEqualTo() method.
+      <li>AssertThatJava8Optional and AssertThatGuavaOptional inspections do not longer try to fix
+          assertThat(optional).isEqualTo(Optional.fromNullable(expression)) to contains()
+          when expression is not a non-null constant expression.
     </ul>
   <p>Full changelog available at <a href="https://github.com/chrisly42/cajon-plugin#changelog">Github project site</a>.</p>
 """
@@ -73,7 +64,7 @@ test {
 }
 
 jacoco {
-    toolVersion = '0.8.3'
+    toolVersion = '0.8.4'
 }
 
 jacocoTestReport {

gradle/wrapper/gradle-wrapper.properties

@@ -3,4 +3,4 @@ distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-5.2.1-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-5.4.1-all.zip

src/main/java/de/platon42/intellij/plugins/cajon/AssertJClassNames.kt

@@ -14,6 +14,10 @@ class AssertJClassNames {
         const val DESCRIPTABLE_INTERFACE = "org.assertj.core.api.Descriptable"
         @NonNls
         const val EXTENSION_POINTS_INTERFACE = "org.assertj.core.api.ExtensionPoints"
+        @NonNls
+        const val ENUMERABLE_ASSERT_INTERFACE = "org.assertj.core.api.EnumerableAssert"
+        @NonNls
+        const val OBJECT_ENUMERABLE_ASSERT_INTERFACE = "org.assertj.core.api.ObjectEnumerableAssert"
 
         @NonNls
         const val ASSERT_INTERFACE = "org.assertj.core.api.Assert"
@@ -34,7 +38,7 @@ class AssertJClassNames {
         @NonNls
         const val ABSTRACT_ITERABLE_ASSERT_CLASSNAME = "org.assertj.core.api.AbstractIterableAssert"
         @NonNls
-        const val ABSTRACT_ENUMERABLE_ASSERT_CLASSNAME = "org.assertj.core.api.EnumerableAssert"
+        const val ABSTRACT_OPTIONAL_ASSERT_CLASSNAME = "org.assertj.core.api.AbstractOptionalAssert"
         @NonNls
         const val EXTRACTORS_CLASSNAME = "org.assertj.core.extractor.Extractors"
 
@@ -42,5 +46,7 @@ class AssertJClassNames {
         const val GUAVA_OPTIONAL_CLASSNAME = "com.google.common.base.Optional"
         @NonNls
         const val GUAVA_ASSERTIONS_CLASSNAME = "org.assertj.guava.api.Assertions"
+        @NonNls
+        const val GUAVA_OPTIONAL_ASSERTIONS_CLASSNAME = "org.assertj.guava.api.OptionalAssert"
     }
 }

src/main/java/de/platon42/intellij/plugins/cajon/CommonMatchers.kt

@@ -23,16 +23,31 @@ val DESCRIBED_AS = CallMatcher.instanceCall(AssertJClassNames.DESCRIPTABLE_INTER
 val WITH_REPRESENTATION_AND_SUCH = CallMatcher.instanceCall(AssertJClassNames.ASSERT_INTERFACE, "withRepresentation", "withThreadDumpOnError")!!
 val USING_COMPARATOR = CallMatcher.instanceCall(AssertJClassNames.ASSERT_INTERFACE, "usingComparator", "usingDefaultComparator")!!
 val IN_HEXADECIMAL_OR_BINARY = CallMatcher.instanceCall(AssertJClassNames.ABSTRACT_ASSERT_CLASSNAME, MethodNames.IN_HEXADECIMAL, MethodNames.IN_BINARY)!!
-val EXTENSION_POINTS = CallMatcher.instanceCall(AssertJClassNames.EXTENSION_POINTS_INTERFACE, "is", "isNot", "has", "doesNotHave", "satisfies")!!
+val EXTENSION_POINTS = CallMatcher.instanceCall(
+    AssertJClassNames.EXTENSION_POINTS_INTERFACE,
+    "is", "isNot", "has", "doesNotHave",
+    "satisfies"
+)!!
+val MORE_EXTENSION_POINTS = CallMatcher.instanceCall(
+    AssertJClassNames.OBJECT_ENUMERABLE_ASSERT_INTERFACE,
+    "are", "areNot", "have", "doNotHave",
+    "areAtLeast", "areAtLeastOne", "areAtMost", "areExactly",
+    "haveAtLeastOne", "haveAtLeast", "haveAtMost", "haveExactly",
+    "hasOnlyOneElementSatisfying", "anyMatch", "noneMatch", "anySatisfy", "noneSatisfy"
+)!!
 
-val NOT_ACTUAL_ASSERTIONS = CallMatcher.anyOf(
-    ALL_ASSERT_THAT_MATCHERS,
+val COMPLEX_CALLS_THAT_MAKES_STUFF_TRICKY = CallMatcher.anyOf(
     DESCRIBED_AS,
     WITH_REPRESENTATION_AND_SUCH,
     USING_COMPARATOR,
     IN_HEXADECIMAL_OR_BINARY
 )!!
 
+val NOT_ACTUAL_ASSERTIONS = CallMatcher.anyOf(
+    ALL_ASSERT_THAT_MATCHERS,
+    COMPLEX_CALLS_THAT_MAKES_STUFF_TRICKY
+)!!
+
 val KNOWN_METHODS_WITH_SIDE_EFFECTS = CallMatcher.anyOf(
     CallMatcher.instanceCall(CommonClassNames.JAVA_UTIL_ITERATOR, "next")
 )!!

src/main/java/de/platon42/intellij/plugins/cajon/Extensions.kt

@@ -100,13 +100,31 @@ fun PsiMethodCallExpression.getExpectedBooleanResult(): Boolean? {
     return null
 }
 
+fun PsiMethodCallExpression.getExpectedNullNonNullResult(): Boolean? {
+    val isNull = AbstractAssertJInspection.IS_NULL.test(this)
+    val isNotNull = AbstractAssertJInspection.IS_NOT_NULL.test(this)
+    if (isNull || isNotNull) {
+        return isNotNull
+    } else {
+        val isEqualTo = CallMatcher.anyOf(AbstractAssertJInspection.IS_EQUAL_TO_OBJECT, AbstractAssertJInspection.IS_EQUAL_TO_STRING).test(this)
+        val isNotEqualTo = AbstractAssertJInspection.IS_NOT_EQUAL_TO_OBJECT.test(this)
+        if ((isEqualTo || isNotEqualTo) && firstArg.type == PsiType.NULL) {
+            return isNotEqualTo
+        }
+    }
+    return null
+}
+
 fun PsiMethodCallExpression.calculateConstantParameterValue(argIndex: Int): Any? {
     if (argIndex >= argumentList.expressions.size) return null
-    val valueExpression = getArg(argIndex)
+    return getArg(argIndex).calculateConstantValue()
+}
+
+fun PsiExpression.calculateConstantValue(): Any? {
     val constantEvaluationHelper = JavaPsiFacade.getInstance(project).constantEvaluationHelper
-    val value = constantEvaluationHelper.computeConstantExpression(valueExpression)
+    val value = constantEvaluationHelper.computeConstantExpression(this)
     if (value == null) {
-        val field = (valueExpression as? PsiReferenceExpression)?.resolve() as? PsiField
+        val field = (this as? PsiReferenceExpression)?.resolve() as? PsiField
         if (field?.containingClass?.qualifiedName == CommonClassNames.JAVA_LANG_BOOLEAN) {
             return when (field.name) {
                 "TRUE" -> true
@@ -126,21 +144,41 @@ fun PsiExpression.getAllTheSameExpectedBooleanConstants(): Boolean? {
     for (methodCall in methodsToView) {
         val expectedResult = methodCall.getExpectedBooleanResult()
         if (expectedResult != null) {
-            if ((lockedResult != null) && (lockedResult != expectedResult)) {
-                return null
-            }
+            if ((lockedResult != null) && (lockedResult != expectedResult)) return null
             lockedResult = expectedResult
         } else {
             val isNotConstant = CallMatcher.anyOf(
                 EXTENSION_POINTS,
+                MORE_EXTENSION_POINTS,
                 AbstractAssertJInspection.IS_EQUAL_TO_BOOLEAN,
                 AbstractAssertJInspection.IS_EQUAL_TO_OBJECT,
                 AbstractAssertJInspection.IS_NOT_EQUAL_TO_BOOLEAN,
                 AbstractAssertJInspection.IS_NOT_EQUAL_TO_OBJECT
             ).test(methodCall)
-            if (isNotConstant) {
-                return null
-            }
+            if (isNotConstant) return null
+        }
+    }
+    return lockedResult
+}
+
+fun PsiExpression.getAllTheSameNullNotNullConstants(): Boolean? {
+    val assertThatMethodCall = findStaticMethodCall() ?: return null
+    var lockedResult: Boolean? = null
+    val methodsToView = generateSequence(assertThatMethodCall) { PsiTreeUtil.getParentOfType(it, PsiMethodCallExpression::class.java) }
+
+    for (methodCall in methodsToView) {
+        val expectedResult = methodCall.getExpectedNullNonNullResult()
+        if (expectedResult != null) {
+            if ((lockedResult != null) && (lockedResult != expectedResult)) return null
+            lockedResult = expectedResult
+        } else {
+            val isNotConstant = CallMatcher.anyOf(
+                EXTENSION_POINTS,
+                MORE_EXTENSION_POINTS,
+                AbstractAssertJInspection.IS_EQUAL_TO_OBJECT,
+                AbstractAssertJInspection.IS_NOT_EQUAL_TO_OBJECT
+            ).test(methodCall)
+            if (isNotConstant) return null
         }
     }
     return lockedResult

src/main/java/de/platon42/intellij/plugins/cajon/Helper.kt

@@ -18,6 +18,10 @@ fun createAssertThat(context: PsiElement, baseclass: String, actualExpression: P
     return createMethodCall(context, "$baseclass.${MethodNames.ASSERT_THAT}", actualExpression)
 }
 
+fun createAssumeThat(context: PsiElement, actualExpression: PsiExpression): PsiMethodCallExpression {
+    return createMethodCall(context, "${AssertJClassNames.ASSUMPTIONS_CLASSNAME}.${MethodNames.ASSUME_THAT}", actualExpression)
+}
+
 fun createExpectedMethodCall(context: PsiElement, methodName: String, vararg arguments: PsiElement): PsiMethodCallExpression {
     return createMethodCall(context, "a.$methodName", *arguments)
 }

src/main/java/de/platon42/intellij/plugins/cajon/MethodNames.kt

@@ -32,6 +32,10 @@ class MethodNames {
         const val IS_SAME_AS = "isSameAs"
         @NonNls
         const val IS_NOT_SAME_AS = "isNotSameAs"
+
+        @NonNls
+        const val HAS_TO_STRING = "hasToString"
+
         @NonNls
         const val IS_GREATER_THAN = "isGreaterThan"
         @NonNls
@@ -61,6 +65,8 @@ class MethodNames {
         @NonNls
         const val IS_NOT_INSTANCE_OF = "isNotInstanceOf"
 
+        @NonNls
+        const val IS_NULL_OR_EMPTY = "isNullOrEmpty" // terminal, returns void
         @NonNls
         const val IS_EMPTY = "isEmpty" // terminal, returns void
         @NonNls
@@ -80,10 +86,22 @@ class MethodNames {
         @NonNls
         const val CONTAINS = "contains"
         @NonNls
+        const val CONTAINS_ONLY_ONCE = "containsOnlyOnce"
+        @NonNls
         const val DOES_NOT_CONTAIN = "doesNotContain"
         @NonNls
         const val CONTAINS_EXACTLY = "containsExactly"
         @NonNls
+        const val CONTAINS_ALL = "containsAll"
+        @NonNls
+        const val CONTAINS_KEY = "containsKey"
+        @NonNls
+        const val DOES_NOT_CONTAIN_KEY = "doesNotContainKey"
+        @NonNls
+        const val CONTAINS_VALUE = "containsValue"
+        @NonNls
+        const val DOES_NOT_CONTAIN_VALUE = "doesNotContainValue"
+        @NonNls
         const val IS_EQUAL_TO_IC = "isEqualToIgnoringCase"
         @NonNls
         const val IS_NOT_EQUAL_TO_IC = "isNotEqualToIgnoringCase"

src/main/java/de/platon42/intellij/plugins/cajon/inspections/AbstractAssertJInspection.kt

@@ -12,10 +12,11 @@ import com.siyeh.ig.callMatcher.CallMatcher
 import de.platon42.intellij.plugins.cajon.AssertJClassNames.Companion.ABSTRACT_ASSERT_CLASSNAME
 import de.platon42.intellij.plugins.cajon.AssertJClassNames.Companion.ABSTRACT_BOOLEAN_ASSERT_CLASSNAME
 import de.platon42.intellij.plugins.cajon.AssertJClassNames.Companion.ABSTRACT_COMPARABLE_ASSERT_CLASSNAME
-import de.platon42.intellij.plugins.cajon.AssertJClassNames.Companion.ABSTRACT_ENUMERABLE_ASSERT_CLASSNAME
 import de.platon42.intellij.plugins.cajon.AssertJClassNames.Companion.ABSTRACT_INTEGER_ASSERT_CLASSNAME
+import de.platon42.intellij.plugins.cajon.AssertJClassNames.Companion.ABSTRACT_STRING_ASSERT_CLASSNAME
 import de.platon42.intellij.plugins.cajon.AssertJClassNames.Companion.ASSERTIONS_CLASSNAME
 import de.platon42.intellij.plugins.cajon.AssertJClassNames.Companion.ASSERT_INTERFACE
+import de.platon42.intellij.plugins.cajon.AssertJClassNames.Companion.ENUMERABLE_ASSERT_INTERFACE
 import de.platon42.intellij.plugins.cajon.AssertJClassNames.Companion.GUAVA_ASSERTIONS_CLASSNAME
 import de.platon42.intellij.plugins.cajon.AssertJClassNames.Companion.GUAVA_OPTIONAL_CLASSNAME
 import de.platon42.intellij.plugins.cajon.MethodNames
@@ -81,6 +82,8 @@ open class AbstractAssertJInspection : AbstractBaseJavaLocalInspectionTool() {
 
         val IS_EQUAL_TO_OBJECT = CallMatcher.instanceCall(ASSERT_INTERFACE, MethodNames.IS_EQUAL_TO)
             .parameterTypes(CommonClassNames.JAVA_LANG_OBJECT)!!
+        val IS_EQUAL_TO_STRING = CallMatcher.instanceCall(ABSTRACT_STRING_ASSERT_CLASSNAME, MethodNames.IS_EQUAL_TO)
+            .parameterTypes(CommonClassNames.JAVA_LANG_STRING)!!
         val IS_NOT_EQUAL_TO_OBJECT = CallMatcher.instanceCall(ASSERT_INTERFACE, MethodNames.IS_NOT_EQUAL_TO)
             .parameterTypes(CommonClassNames.JAVA_LANG_OBJECT)!!
         val IS_EQUAL_TO_BOOLEAN = CallMatcher.instanceCall(ABSTRACT_BOOLEAN_ASSERT_CLASSNAME, MethodNames.IS_EQUAL_TO)
@@ -93,7 +96,14 @@ open class AbstractAssertJInspection : AbstractBaseJavaLocalInspectionTool() {
         val IS_NOT_SAME_AS_OBJECT = CallMatcher.instanceCall(ASSERT_INTERFACE, MethodNames.IS_NOT_SAME_AS)
             .parameterTypes(CommonClassNames.JAVA_LANG_OBJECT)!!
 
-        val HAS_SIZE = CallMatcher.instanceCall(ABSTRACT_ENUMERABLE_ASSERT_CLASSNAME, MethodNames.HAS_SIZE)
+        val IS_NULL = CallMatcher.instanceCall(ASSERT_INTERFACE, MethodNames.IS_NULL)
+            .parameterCount(0)!!
+        val IS_NOT_NULL = CallMatcher.instanceCall(ASSERT_INTERFACE, MethodNames.IS_NOT_NULL)
+            .parameterCount(0)!!
+
+        val IS_NOT_EMPTY = CallMatcher.instanceCall(ENUMERABLE_ASSERT_INTERFACE, MethodNames.IS_NOT_EMPTY)
+            .parameterCount(0)!!
+        val HAS_SIZE = CallMatcher.instanceCall(ENUMERABLE_ASSERT_INTERFACE, MethodNames.HAS_SIZE)
             .parameterTypes("int")!!
 
         val IS_EQUAL_TO_INT = CallMatcher.instanceCall(ABSTRACT_ASSERT_CLASSNAME, MethodNames.IS_EQUAL_TO)
@@ -129,6 +139,8 @@ open class AbstractAssertJInspection : AbstractBaseJavaLocalInspectionTool() {
             .parameterCount(0)!!
         val OPTIONAL_IS_PRESENT = CallMatcher.instanceCall(CommonClassNames.JAVA_UTIL_OPTIONAL, "isPresent")
             .parameterCount(0)!!
+        val OPTIONAL_OR_ELSE = CallMatcher.instanceCall(CommonClassNames.JAVA_UTIL_OPTIONAL, "orElse")
+            .parameterCount(1)!!
 
         val OPTIONAL_OF = CallMatcher.staticCall(CommonClassNames.JAVA_UTIL_OPTIONAL, "of")
             .parameterCount(1)!!
@@ -141,6 +153,8 @@ open class AbstractAssertJInspection : AbstractBaseJavaLocalInspectionTool() {
             .parameterCount(0)!!
         val GUAVA_OPTIONAL_IS_PRESENT = CallMatcher.instanceCall(GUAVA_OPTIONAL_CLASSNAME, "isPresent")
             .parameterCount(0)!!
+        val GUAVA_OPTIONAL_OR_NULL = CallMatcher.instanceCall(GUAVA_OPTIONAL_CLASSNAME, "orNull")
+            .parameterCount(0)!!
 
         val GUAVA_OPTIONAL_OF = CallMatcher.staticCall(GUAVA_OPTIONAL_CLASSNAME, "of")
             .parameterCount(1)!!

src/main/java/de/platon42/intellij/plugins/cajon/inspections/AbstractJUnitAssertInspection.kt

@@ -9,6 +9,8 @@ open class AbstractJUnitAssertInspection : AbstractBaseJavaLocalInspectionTool()
     companion object {
         @NonNls
         const val JUNIT_ASSERT_CLASSNAME = "org.junit.Assert"
+        @NonNls
+        const val JUNIT_ASSUME_CLASSNAME = "org.junit.Assume"
 
         @NonNls
         const val ASSERT_TRUE_METHOD = "assertTrue"
@@ -28,6 +30,16 @@ open class AbstractJUnitAssertInspection : AbstractBaseJavaLocalInspectionTool()
         const val ASSERT_NOT_SAME_METHOD = "assertNotSame"
         @NonNls
         const val ASSERT_ARRAY_EQUALS_METHOD = "assertArrayEquals"
+
+        @NonNls
+        const val ASSUME_TRUE_METHOD = "assumeTrue"
+        @NonNls
+        const val ASSUME_FALSE_METHOD = "assumeFalse"
+        @NonNls
+        const val ASSUME_NOT_NULL_METHOD = "assumeNotNull"
+        @NonNls
+        const val ASSUME_NO_EXCEPTION = "assumeNoException"
+
     }
 
     override fun getGroupDisplayName(): String {

src/main/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatBinaryExpressionInspection.kt

@@ -5,15 +5,14 @@ import com.intellij.codeInspection.ProblemsHolder
 import com.intellij.psi.*
 import com.intellij.psi.util.TypeConversionUtil
 import de.platon42.intellij.plugins.cajon.*
-import de.platon42.intellij.plugins.cajon.quickfixes.MoveOutMethodCallExpressionQuickFix
 import de.platon42.intellij.plugins.cajon.quickfixes.SplitBinaryExpressionMethodCallQuickFix
 
 class AssertThatBinaryExpressionInspection : AbstractAssertJInspection() {
 
     companion object {
         private const val DISPLAY_NAME = "Asserting a binary expression"
-        private const val SPLIT_EXPRESSION_DESCRIPTION_TEMPLATE = "Split %s expression out of assertThat()"
-        private const val MORE_MEANINGFUL_MESSAGE_TEMPLATE = "Moving %s expression out of assertThat() would be more meaningful"
+        private const val SPLIT_EXPRESSION_DESCRIPTION_TEMPLATE = "Split binary expression out of assertThat()"
+        private const val MORE_MEANINGFUL_MESSAGE_TEMPLATE = "Moving binary expression out of assertThat() would be more meaningful"
     }
 
     override fun getDisplayName() = DISPLAY_NAME
@@ -22,36 +21,25 @@ class AssertThatBinaryExpressionInspection : AbstractAssertJInspection() {
         return object : JavaElementVisitor() {
             override fun visitExpressionStatement(statement: PsiExpressionStatement) {
                 super.visitExpressionStatement(statement)
-                if (!statement.hasAssertThat()) {
-                    return
-                }
+                if (!statement.hasAssertThat()) return
                 val staticMethodCall = statement.findStaticMethodCall() ?: return
-                if (!ASSERT_THAT_BOOLEAN.test(staticMethodCall)) {
-                    return
-                }
+                if (!ASSERT_THAT_BOOLEAN.test(staticMethodCall)) return
 
                 val expectedCallExpression = statement.findOutmostMethodCall() ?: return
                 val expectedResult = expectedCallExpression.getAllTheSameExpectedBooleanConstants() ?: return
 
-                val assertThatArgument = staticMethodCall.firstArg
-                if (assertThatArgument is PsiMethodCallExpression && OBJECT_EQUALS.test(assertThatArgument)) {
-                    val replacementMethod = expectedResult.map(MethodNames.IS_EQUAL_TO, MethodNames.IS_NOT_EQUAL_TO)
-                    registerSplitMethod(holder, expectedCallExpression, "${MethodNames.EQUALS}()", replacementMethod, ::MoveOutMethodCallExpressionQuickFix)
-                    return
-                }
-
-                val binaryExpression = assertThatArgument as? PsiBinaryExpression ?: return
+                val binaryExpression = staticMethodCall.firstArg as? PsiBinaryExpression ?: return
 
                 val leftType = binaryExpression.lOperand.type ?: return
                 val rightType = binaryExpression.rOperand?.type ?: return
 
                 val bothTypes = listOf(leftType, rightType)
                 val (isLeftNull, isRightNull) = bothTypes.map(TypeConversionUtil::isNullType)
-                if (isLeftNull && isRightNull) {
-                    return
-                } else if (isLeftNull || isRightNull) {
+
+                if (isLeftNull && isRightNull) return
+                if (isLeftNull || isRightNull) {
                     val replacementMethod = expectedResult.map(MethodNames.IS_NULL, MethodNames.IS_NOT_NULL)
-                    registerSplitMethod(holder, expectedCallExpression, "binary", replacementMethod) { desc, method ->
+                    registerSplitMethod(holder, expectedCallExpression, replacementMethod) { desc, method ->
                         SplitBinaryExpressionMethodCallQuickFix(desc, method, pickRightOperand = isLeftNull, noExpectedExpression = true)
                     }
                     return
@@ -73,7 +61,7 @@ class AssertThatBinaryExpressionInspection : AbstractAssertJInspection() {
                     (isPrimitive || isNumericType).map(TOKEN_TO_ASSERTJ_FOR_PRIMITIVE_MAP, TOKEN_TO_ASSERTJ_FOR_OBJECT_MAPPINGS)
                 val replacementMethod = mappingToUse[tokenType] ?: return
 
-                registerSplitMethod(holder, expectedCallExpression, "binary", replacementMethod) { desc, method ->
+                registerSplitMethod(holder, expectedCallExpression, replacementMethod) { desc, method ->
                     SplitBinaryExpressionMethodCallQuickFix(desc, method, pickRightOperand = swapExpectedAndActual)
                 }
             }
@@ -83,13 +71,10 @@ class AssertThatBinaryExpressionInspection : AbstractAssertJInspection() {
     private fun registerSplitMethod(
         holder: ProblemsHolder,
         expression: PsiMethodCallExpression,
-        type: String,
         replacementMethod: String,
         quickFixSupplier: (String, String) -> LocalQuickFix
     ) {
-        val description = SPLIT_EXPRESSION_DESCRIPTION_TEMPLATE.format(type)
-        val message = MORE_MEANINGFUL_MESSAGE_TEMPLATE.format(type)
-        val quickfix = quickFixSupplier(description, replacementMethod)
-        holder.registerProblem(expression, message, quickfix)
+        val quickfix = quickFixSupplier(SPLIT_EXPRESSION_DESCRIPTION_TEMPLATE, replacementMethod)
+        holder.registerProblem(expression, MORE_MEANINGFUL_MESSAGE_TEMPLATE, quickfix)
     }
 }

src/main/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatBooleanConditionInspection.kt

@@ -20,24 +20,17 @@ class AssertThatBooleanConditionInspection : AbstractAssertJInspection() {
         return object : JavaElementVisitor() {
             override fun visitMethodCallExpression(expression: PsiMethodCallExpression) {
                 super.visitMethodCallExpression(expression)
-                if (!expression.hasAssertThat()) {
-                    return
-                }
+                if (!expression.hasAssertThat()) return
                 val matchingCalls = listOf(
                     IS_EQUAL_TO_OBJECT, IS_EQUAL_TO_BOOLEAN,
                     IS_NOT_EQUAL_TO_OBJECT, IS_NOT_EQUAL_TO_BOOLEAN
                 ).map { it.test(expression) }
-                if (matchingCalls.none { it }) {
-                    return
-                }
-                if (!checkAssertedType(expression, ABSTRACT_BOOLEAN_ASSERT_CLASSNAME)) {
-                    return
-                }
+                if (matchingCalls.none { it }) return
+                if (!checkAssertedType(expression, ABSTRACT_BOOLEAN_ASSERT_CLASSNAME)) return
 
                 val expectedExpression = expression.firstArg
-                if (!TypeConversionUtil.isBooleanType(expectedExpression.type)) {
-                    return
-                }
+                if (!TypeConversionUtil.isBooleanType(expectedExpression.type)) return
+
                 val expectedResult = expression.calculateConstantParameterValue(0) as? Boolean ?: return
                 val flippedBooleanTest = matchingCalls.drop(2).any { it }
 

src/main/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatCollectionOrMapExpressionInspection.kt

@@ -0,0 +1,70 @@
+package de.platon42.intellij.plugins.cajon.inspections
+
+import com.intellij.codeInspection.ProblemsHolder
+import com.intellij.psi.*
+import com.siyeh.ig.callMatcher.CallMatcher
+import de.platon42.intellij.plugins.cajon.*
+import de.platon42.intellij.plugins.cajon.quickfixes.MoveOutMethodCallExpressionQuickFix
+
+class AssertThatCollectionOrMapExpressionInspection : AbstractAssertJInspection() {
+
+    companion object {
+        private const val DISPLAY_NAME = "Asserting a collection or map specific expression"
+
+        private val MAPPINGS = listOf(
+            Mapping(
+                CallMatcher.anyOf(
+                    CallMatcher.instanceCall(CommonClassNames.JAVA_UTIL_COLLECTION, "isEmpty").parameterCount(0),
+                    CallMatcher.instanceCall(CommonClassNames.JAVA_UTIL_MAP, "isEmpty").parameterCount(0)
+                ),
+                MethodNames.IS_EMPTY, MethodNames.IS_NOT_EMPTY
+            ),
+            Mapping(
+                CallMatcher.instanceCall(CommonClassNames.JAVA_UTIL_COLLECTION, "contains").parameterCount(1),
+                MethodNames.CONTAINS, MethodNames.DOES_NOT_CONTAIN
+            ),
+            Mapping(
+                CallMatcher.instanceCall(CommonClassNames.JAVA_UTIL_COLLECTION, "containsAll").parameterCount(1),
+                MethodNames.CONTAINS_ALL, null
+            ),
+            Mapping(
+                CallMatcher.instanceCall(CommonClassNames.JAVA_UTIL_MAP, "containsKey").parameterCount(1),
+                MethodNames.CONTAINS_KEY, MethodNames.DOES_NOT_CONTAIN_KEY
+            ),
+            Mapping(
+                CallMatcher.instanceCall(CommonClassNames.JAVA_UTIL_MAP, "containsValue").parameterCount(1),
+                MethodNames.CONTAINS_VALUE, MethodNames.DOES_NOT_CONTAIN_VALUE
+            )
+        )
+    }
+
+    override fun getDisplayName() = DISPLAY_NAME
+
+    override fun buildVisitor(holder: ProblemsHolder, isOnTheFly: Boolean): PsiElementVisitor {
+        return object : JavaElementVisitor() {
+            override fun visitExpressionStatement(statement: PsiExpressionStatement) {
+                super.visitExpressionStatement(statement)
+                if (!statement.hasAssertThat()) return
+                val staticMethodCall = statement.findStaticMethodCall() ?: return
+                if (!ASSERT_THAT_BOOLEAN.test(staticMethodCall)) return
+
+                val assertThatArgument = staticMethodCall.firstArg as? PsiMethodCallExpression ?: return
+                val mapping = MAPPINGS.firstOrNull { it.callMatcher.test(assertThatArgument) } ?: return
+
+                val expectedCallExpression = statement.findOutmostMethodCall() ?: return
+                val expectedResult = expectedCallExpression.getAllTheSameExpectedBooleanConstants() ?: return
+
+                val replacementMethod = if (expectedResult) mapping.replacementForTrue else mapping.replacementForFalse ?: return
+                registerMoveOutMethod(holder, expectedCallExpression, assertThatArgument, replacementMethod) { desc, method ->
+                    MoveOutMethodCallExpressionQuickFix(desc, method)
+                }
+            }
+        }
+    }
+
+    private class Mapping(
+        val callMatcher: CallMatcher,
+        val replacementForTrue: String,
+        val replacementForFalse: String?
+    )
+}

src/main/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatEnumerableIsEmptyInspection.kt

@@ -21,13 +21,9 @@ class AssertThatEnumerableIsEmptyInspection : AbstractAssertJInspection() {
         return object : JavaElementVisitor() {
             override fun visitMethodCallExpression(expression: PsiMethodCallExpression) {
                 super.visitMethodCallExpression(expression)
-                if (!expression.hasAssertThat()) {
-                    return
-                }
+                if (!expression.hasAssertThat()) return
                 val isLastExpression = expression.parent is PsiStatement
-                if (!(HAS_SIZE.test(expression) && isLastExpression)) {
-                    return
-                }
+                if (!(HAS_SIZE.test(expression) && isLastExpression)) return
 
                 val value = expression.calculateConstantParameterValue(0) ?: return
                 if (value == 0) {

src/main/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatGuavaOptionalInspection.kt

@@ -21,20 +21,16 @@ class AssertThatGuavaOptionalInspection : AbstractAssertJInspection() {
         return object : JavaElementVisitor() {
             override fun visitExpressionStatement(statement: PsiExpressionStatement) {
                 super.visitExpressionStatement(statement)
-                if (!statement.hasAssertThat()) {
-                    return
-                }
+                if (!statement.hasAssertThat()) return
                 val staticMethodCall = statement.findStaticMethodCall() ?: return
 
-                if (!checkPreconditions(staticMethodCall)) {
-                    return
-                }
-                val actualExpression = staticMethodCall.firstArg as? PsiMethodCallExpression ?: return
+                if (!checkPreconditions(staticMethodCall)) return
 
+                val actualExpression = staticMethodCall.firstArg as? PsiMethodCallExpression ?: return
                 val outmostMethodCall = statement.findOutmostMethodCall() ?: return
                 if (GUAVA_OPTIONAL_GET.test(actualExpression)) {
                     val expectedCallExpression = staticMethodCall.gatherAssertionCalls().singleOrNull() ?: return
-                    if (IS_EQUAL_TO_OBJECT.test(expectedCallExpression)) {
+                    if (CallMatcher.anyOf(IS_EQUAL_TO_OBJECT, IS_EQUAL_TO_STRING).test(expectedCallExpression)) {
                         registerMoveOutMethod(holder, outmostMethodCall, actualExpression, MethodNames.CONTAINS) { desc, method ->
                             QuickFixWithPostfixDelegate(
                                 RemoveActualOutmostMethodCallQuickFix(desc, method),
@@ -51,23 +47,32 @@ class AssertThatGuavaOptionalInspection : AbstractAssertJInspection() {
                             ForGuavaPostFix.REPLACE_BY_GUAVA_ASSERT_THAT_AND_STATIC_IMPORT
                         )
                     }
+                } else if (GUAVA_OPTIONAL_OR_NULL.test(actualExpression)) {
+                    val expectedPresence = outmostMethodCall.getAllTheSameNullNotNullConstants() ?: return
+                    val replacementMethod = expectedPresence.map(MethodNames.IS_PRESENT, MethodNames.IS_ABSENT)
+                    registerMoveOutMethod(holder, outmostMethodCall, actualExpression, replacementMethod) { desc, method ->
+                        QuickFixWithPostfixDelegate(
+                            MoveOutMethodCallExpressionQuickFix(desc, method, useNullNonNull = true),
+                            ForGuavaPostFix.REPLACE_BY_GUAVA_ASSERT_THAT_AND_STATIC_IMPORT
+                        )
+                    }
                 }
             }
 
             override fun visitMethodCallExpression(expression: PsiMethodCallExpression) {
                 super.visitMethodCallExpression(expression)
-                if (!expression.hasAssertThat()) {
-                    return
-                }
+                if (!expression.hasAssertThat()) return
                 val staticMethodCall = expression.findStaticMethodCall() ?: return
-                if (!checkPreconditions(staticMethodCall)) {
-                    return
-                }
+                if (!checkPreconditions(staticMethodCall)) return
+
                 // We're not calling an assertThat() from Guava, but a core-AssertJ one!
                 // We need to replace that by the Guava one, if we want to apply a formally correct fix.
                 if (IS_EQUAL_TO_OBJECT.test(expression)) {
                     val innerExpectedCall = expression.firstArg as? PsiMethodCallExpression ?: return
                     if (CallMatcher.anyOf(GUAVA_OPTIONAL_OF, GUAVA_OPTIONAL_FROM_NULLABLE).test(innerExpectedCall)) {
+                        if (GUAVA_OPTIONAL_FROM_NULLABLE.test(innerExpectedCall)) {
+                            innerExpectedCall.firstArg.calculateConstantValue() ?: return
+                        }
                         registerRemoveExpectedOutmostMethod(holder, expression, expression, MethodNames.CONTAINS) { desc, method ->
                             QuickFixWithPostfixDelegate(
                                 UnwrapExpectedStaticMethodCallQuickFix(desc, method),

src/main/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatInstanceOfInspection.kt

@@ -20,13 +20,9 @@ class AssertThatInstanceOfInspection : AbstractAssertJInspection() {
         return object : JavaElementVisitor() {
             override fun visitExpressionStatement(statement: PsiExpressionStatement) {
                 super.visitExpressionStatement(statement)
-                if (!statement.hasAssertThat()) {
-                    return
-                }
+                if (!statement.hasAssertThat()) return
                 val staticMethodCall = statement.findStaticMethodCall() ?: return
-                if (!ASSERT_THAT_BOOLEAN.test(staticMethodCall)) {
-                    return
-                }
+                if (!ASSERT_THAT_BOOLEAN.test(staticMethodCall)) return
 
                 val expectedCallExpression = statement.findOutmostMethodCall() ?: return
                 val expectedResult = expectedCallExpression.getAllTheSameExpectedBooleanConstants() ?: return

src/main/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatInvertedBooleanConditionInspection.kt

@@ -18,13 +18,9 @@ class AssertThatInvertedBooleanConditionInspection : AbstractAssertJInspection()
         return object : JavaElementVisitor() {
             override fun visitMethodCallExpression(expression: PsiMethodCallExpression) {
                 super.visitMethodCallExpression(expression)
-                if (!expression.hasAssertThat()) {
-                    return
-                }
+                if (!expression.hasAssertThat()) return
                 val staticMethodCall = expression.findStaticMethodCall() ?: return
-                if (!ASSERT_THAT_BOOLEAN.test(staticMethodCall)) {
-                    return
-                }
+                if (!ASSERT_THAT_BOOLEAN.test(staticMethodCall)) return
                 expression.getExpectedBooleanResult() ?: return
 
                 val prefixExpression = staticMethodCall.firstArg as? PsiPrefixExpression ?: return

src/main/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatJava8OptionalInspection.kt

@@ -1,10 +1,7 @@
 package de.platon42.intellij.plugins.cajon.inspections
 
 import com.intellij.codeInspection.ProblemsHolder
-import com.intellij.psi.JavaElementVisitor
-import com.intellij.psi.PsiElementVisitor
-import com.intellij.psi.PsiExpressionStatement
-import com.intellij.psi.PsiMethodCallExpression
+import com.intellij.psi.*
 import com.siyeh.ig.callMatcher.CallMatcher
 import de.platon42.intellij.plugins.cajon.*
 import de.platon42.intellij.plugins.cajon.quickfixes.MoveOutMethodCallExpressionQuickFix
@@ -23,19 +20,15 @@ class AssertThatJava8OptionalInspection : AbstractAssertJInspection() {
         return object : JavaElementVisitor() {
             override fun visitExpressionStatement(statement: PsiExpressionStatement) {
                 super.visitExpressionStatement(statement)
-                if (!statement.hasAssertThat()) {
-                    return
-                }
+                if (!statement.hasAssertThat()) return
                 val staticMethodCall = statement.findStaticMethodCall() ?: return
-                if (!ASSERT_THAT_ANY.test(staticMethodCall)) {
-                    return
-                }
-                val actualExpression = staticMethodCall.firstArg as? PsiMethodCallExpression ?: return
+                if (!ASSERT_THAT_ANY.test(staticMethodCall)) return
 
+                val actualExpression = staticMethodCall.firstArg as? PsiMethodCallExpression ?: return
                 val outmostMethodCall = statement.findOutmostMethodCall() ?: return
                 if (OPTIONAL_GET.test(actualExpression)) {
                     val expectedCallExpression = staticMethodCall.gatherAssertionCalls().singleOrNull() ?: return
-                    if (IS_EQUAL_TO_OBJECT.test(expectedCallExpression)) {
+                    if (CallMatcher.anyOf(IS_EQUAL_TO_OBJECT, IS_EQUAL_TO_STRING).test(expectedCallExpression)) {
                         registerMoveOutMethod(holder, outmostMethodCall, actualExpression, MethodNames.CONTAINS) { desc, method ->
                             RemoveActualOutmostMethodCallQuickFix(desc, method)
                         }
@@ -50,21 +43,26 @@ class AssertThatJava8OptionalInspection : AbstractAssertJInspection() {
                     registerMoveOutMethod(holder, outmostMethodCall, actualExpression, replacementMethod) { desc, method ->
                         MoveOutMethodCallExpressionQuickFix(desc, method)
                     }
+                } else if (OPTIONAL_OR_ELSE.test(actualExpression) && (actualExpression.firstArg.type == PsiType.NULL)) {
+                    val expectedPresence = outmostMethodCall.getAllTheSameNullNotNullConstants() ?: return
+                    val replacementMethod = expectedPresence.map(MethodNames.IS_PRESENT, MethodNames.IS_NOT_PRESENT)
+                    registerMoveOutMethod(holder, outmostMethodCall, actualExpression, replacementMethod) { desc, method ->
+                        MoveOutMethodCallExpressionQuickFix(desc, method, useNullNonNull = true, noExpectedExpression = true)
+                    }
                 }
             }
 
             override fun visitMethodCallExpression(expression: PsiMethodCallExpression) {
                 super.visitMethodCallExpression(expression)
-                if (!expression.hasAssertThat()) {
-                    return
-                }
+                if (!expression.hasAssertThat()) return
                 val staticMethodCall = expression.findStaticMethodCall() ?: return
-                if (!ASSERT_THAT_JAVA8_OPTIONAL.test(staticMethodCall)) {
-                    return
-                }
+                if (!ASSERT_THAT_JAVA8_OPTIONAL.test(staticMethodCall)) return
                 if (IS_EQUAL_TO_OBJECT.test(expression)) {
                     val innerExpectedCall = expression.firstArg as? PsiMethodCallExpression ?: return
                     if (CallMatcher.anyOf(OPTIONAL_OF, OPTIONAL_OF_NULLABLE).test(innerExpectedCall)) {
+                        if (OPTIONAL_OF_NULLABLE.test(innerExpectedCall)) {
+                            innerExpectedCall.firstArg.calculateConstantValue() ?: return
+                        }
                         registerRemoveExpectedOutmostMethod(holder, expression, expression, MethodNames.CONTAINS, ::UnwrapExpectedStaticMethodCallQuickFix)
                     } else if (OPTIONAL_EMPTY.test(innerExpectedCall)) {
                         registerSimplifyMethod(holder, expression, MethodNames.IS_NOT_PRESENT)

src/main/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatObjectExpressionInspection.kt

@@ -0,0 +1,57 @@
+package de.platon42.intellij.plugins.cajon.inspections
+
+import com.intellij.codeInspection.ProblemsHolder
+import com.intellij.psi.*
+import com.siyeh.ig.callMatcher.CallMatcher
+import de.platon42.intellij.plugins.cajon.*
+import de.platon42.intellij.plugins.cajon.quickfixes.HasHashCodeQuickFix
+import de.platon42.intellij.plugins.cajon.quickfixes.MoveOutMethodCallExpressionQuickFix
+import de.platon42.intellij.plugins.cajon.quickfixes.RemoveActualOutmostMethodCallQuickFix
+
+class AssertThatObjectExpressionInspection : AbstractAssertJInspection() {
+
+    companion object {
+        private const val DISPLAY_NAME = "Asserting equals(), toString(), or hashCode()"
+        private const val HASHCODE_MESSAGE_TEMPLATE = "Replacing hashCode() expressions by hasSameHashCode() would be more concise"
+
+        private val OBJECT_TO_STRING = CallMatcher.instanceCall(CommonClassNames.JAVA_LANG_OBJECT, "toString").parameterCount(0)
+        private val OBJECT_HASHCODE = CallMatcher.instanceCall(CommonClassNames.JAVA_LANG_OBJECT, "hashCode").parameterCount(0)
+    }
+
+    override fun getDisplayName() = DISPLAY_NAME
+
+    override fun buildVisitor(holder: ProblemsHolder, isOnTheFly: Boolean): PsiElementVisitor {
+        return object : JavaElementVisitor() {
+            override fun visitExpressionStatement(statement: PsiExpressionStatement) {
+                super.visitExpressionStatement(statement)
+                if (!statement.hasAssertThat()) return
+                val staticMethodCall = statement.findStaticMethodCall() ?: return
+
+                val assertThatArgument = staticMethodCall.firstArg as? PsiMethodCallExpression ?: return
+                val expectedCallExpression = statement.findOutmostMethodCall() ?: return
+                when {
+                    OBJECT_EQUALS.test(assertThatArgument) -> {
+                        val expectedResult = expectedCallExpression.getAllTheSameExpectedBooleanConstants() ?: return
+                        val replacementMethod = expectedResult.map(MethodNames.IS_EQUAL_TO, MethodNames.IS_NOT_EQUAL_TO)
+                        registerMoveOutMethod(holder, expectedCallExpression, assertThatArgument, replacementMethod) { desc, method ->
+                            MoveOutMethodCallExpressionQuickFix(desc, method)
+                        }
+                    }
+                    OBJECT_TO_STRING.test(assertThatArgument) -> {
+                        staticMethodCall.findFluentCallTo(IS_EQUAL_TO_OBJECT) ?: staticMethodCall.findFluentCallTo(IS_EQUAL_TO_STRING) ?: return
+                        registerMoveOutMethod(holder, expectedCallExpression, assertThatArgument, MethodNames.HAS_TO_STRING) { desc, method ->
+                            RemoveActualOutmostMethodCallQuickFix(desc, method)
+                        }
+                    }
+                    OBJECT_HASHCODE.test(assertThatArgument) -> {
+                        val isEqualTo = staticMethodCall.findFluentCallTo(IS_EQUAL_TO_INT) ?: return
+                        val expectedExpression = isEqualTo.firstArg as? PsiMethodCallExpression ?: return
+                        if (OBJECT_HASHCODE.test(expectedExpression)) {
+                            holder.registerProblem(expectedCallExpression, HASHCODE_MESSAGE_TEMPLATE, HasHashCodeQuickFix())
+                        }
+                    }
+                }
+            }
+        }
+    }
+}

src/main/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatObjectIsNullOrNotNullInspection.kt

@@ -2,6 +2,7 @@ package de.platon42.intellij.plugins.cajon.inspections
 
 import com.intellij.codeInspection.ProblemsHolder
 import com.intellij.psi.*
+import com.siyeh.ig.callMatcher.CallMatcher
 import de.platon42.intellij.plugins.cajon.MethodNames
 import de.platon42.intellij.plugins.cajon.firstArg
 import de.platon42.intellij.plugins.cajon.hasAssertThat
@@ -19,15 +20,11 @@ class AssertThatObjectIsNullOrNotNullInspection : AbstractAssertJInspection() {
         return object : JavaElementVisitor() {
             override fun visitMethodCallExpression(expression: PsiMethodCallExpression) {
                 super.visitMethodCallExpression(expression)
-                if (!expression.hasAssertThat()) {
-                    return
-                }
+                if (!expression.hasAssertThat()) return
                 val isNotEqualTo = IS_NOT_EQUAL_TO_OBJECT.test(expression)
-                val isEqualTo = IS_EQUAL_TO_OBJECT.test(expression)
+                val isEqualTo = CallMatcher.anyOf(IS_EQUAL_TO_OBJECT, IS_EQUAL_TO_STRING).test(expression)
                 val isLastExpression = expression.parent is PsiStatement
-                if (!((isEqualTo && isLastExpression) || isNotEqualTo)) {
-                    return
-                }
+                if (!((isEqualTo && isLastExpression) || isNotEqualTo)) return
 
                 if (expression.firstArg.type == PsiType.NULL) {
                     registerSimplifyMethod(holder, expression, isEqualTo.map(MethodNames.IS_NULL, MethodNames.IS_NOT_NULL))

src/main/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatSizeInspection.kt

@@ -74,19 +74,15 @@ class AssertThatSizeInspection : AbstractAssertJInspection() {
         return object : JavaElementVisitor() {
             override fun visitExpressionStatement(statement: PsiExpressionStatement) {
                 super.visitExpressionStatement(statement)
-                if (!statement.hasAssertThat()) {
-                    return
-                }
+                if (!statement.hasAssertThat()) return
                 val staticMethodCall = statement.findStaticMethodCall() ?: return
-                if (!ASSERT_THAT_INT.test(staticMethodCall)) {
-                    return
-                }
+                if (!ASSERT_THAT_INT.test(staticMethodCall)) return
+
                 val actualExpression = staticMethodCall.firstArg
                 val isForArrayOrCollection = isArrayLength(actualExpression) || isCollectionSize(actualExpression)
                 val isForString = isCharSequenceLength(actualExpression)
-                if (!(isForArrayOrCollection || isForString)) {
-                    return
-                }
+                if (!(isForArrayOrCollection || isForString)) return
+
                 val matches = staticMethodCall.collectMethodCallsUpToStatement()
                     .mapNotNull { getMatch(it, isForArrayOrCollection, isForString) }
                     .toList()
@@ -112,22 +108,16 @@ class AssertThatSizeInspection : AbstractAssertJInspection() {
 
             override fun visitMethodCallExpression(expression: PsiMethodCallExpression) {
                 super.visitMethodCallExpression(expression)
-                if (!expression.hasAssertThat()) {
-                    return
-                }
-                val isHasSize = HAS_SIZE.test(expression)
-                if (!(isHasSize)) {
-                    return
-                }
+                if (!expression.hasAssertThat()) return
+                if (!HAS_SIZE.test(expression)) return
                 val actualExpression = expression.firstArg
 
                 val isForArrayOrCollection = isArrayLength(actualExpression) || isCollectionSize(actualExpression)
                 val isForString = isCharSequenceLength(actualExpression)
                 if (!(isForArrayOrCollection
                             || (isForString && checkAssertedType(expression, ABSTRACT_CHAR_SEQUENCE_ASSERT_CLASSNAME)))
-                ) {
-                    return
-                }
+                ) return
+
                 registerConciseMethod(
                     REMOVE_SIZE_DESCRIPTION_TEMPLATE,
                     holder,

src/main/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatStringExpressionInspection.kt

@@ -13,30 +13,30 @@ class AssertThatStringExpressionInspection : AbstractAssertJInspection() {
 
         private val MAPPINGS = listOf(
             Mapping(
-                CallMatcher.instanceCall(CommonClassNames.JAVA_LANG_STRING, "isEmpty").parameterCount(0)!!,
+                CallMatcher.instanceCall(CommonClassNames.JAVA_LANG_STRING, "isEmpty").parameterCount(0),
                 MethodNames.IS_EMPTY, MethodNames.IS_NOT_EMPTY
             ),
             Mapping(
                 CallMatcher.anyOf(
-                    CallMatcher.instanceCall(CommonClassNames.JAVA_LANG_STRING, "equals").parameterCount(1)!!,
-                    CallMatcher.instanceCall(CommonClassNames.JAVA_LANG_STRING, "contentEquals").parameterCount(1)!!
+                    CallMatcher.instanceCall(CommonClassNames.JAVA_LANG_STRING, "equals").parameterCount(1),
+                    CallMatcher.instanceCall(CommonClassNames.JAVA_LANG_STRING, "contentEquals").parameterCount(1)
                 ),
                 MethodNames.IS_EQUAL_TO, MethodNames.IS_NOT_EQUAL_TO
             ),
             Mapping(
-                CallMatcher.instanceCall(CommonClassNames.JAVA_LANG_STRING, "equalsIgnoreCase").parameterTypes(CommonClassNames.JAVA_LANG_STRING)!!,
+                CallMatcher.instanceCall(CommonClassNames.JAVA_LANG_STRING, "equalsIgnoreCase").parameterTypes(CommonClassNames.JAVA_LANG_STRING),
                 MethodNames.IS_EQUAL_TO_IC, MethodNames.IS_NOT_EQUAL_TO_IC
             ),
             Mapping(
-                CallMatcher.instanceCall(CommonClassNames.JAVA_LANG_STRING, "contains").parameterCount(1)!!,
+                CallMatcher.instanceCall(CommonClassNames.JAVA_LANG_STRING, "contains").parameterCount(1),
                 MethodNames.CONTAINS, MethodNames.DOES_NOT_CONTAIN
             ),
             Mapping(
-                CallMatcher.instanceCall(CommonClassNames.JAVA_LANG_STRING, "startsWith").parameterTypes(CommonClassNames.JAVA_LANG_STRING)!!,
+                CallMatcher.instanceCall(CommonClassNames.JAVA_LANG_STRING, "startsWith").parameterTypes(CommonClassNames.JAVA_LANG_STRING),
                 MethodNames.STARTS_WITH, MethodNames.DOES_NOT_START_WITH
             ),
             Mapping(
-                CallMatcher.instanceCall(CommonClassNames.JAVA_LANG_STRING, "endsWith").parameterTypes(CommonClassNames.JAVA_LANG_STRING)!!,
+                CallMatcher.instanceCall(CommonClassNames.JAVA_LANG_STRING, "endsWith").parameterTypes(CommonClassNames.JAVA_LANG_STRING),
                 MethodNames.ENDS_WITH, MethodNames.DOES_NOT_END_WITH
             )
         )
@@ -48,13 +48,10 @@ class AssertThatStringExpressionInspection : AbstractAssertJInspection() {
         return object : JavaElementVisitor() {
             override fun visitExpressionStatement(statement: PsiExpressionStatement) {
                 super.visitExpressionStatement(statement)
-                if (!statement.hasAssertThat()) {
-                    return
-                }
+                if (!statement.hasAssertThat()) return
                 val staticMethodCall = statement.findStaticMethodCall() ?: return
-                if (!ASSERT_THAT_BOOLEAN.test(staticMethodCall)) {
-                    return
-                }
+                if (!ASSERT_THAT_BOOLEAN.test(staticMethodCall)) return
+
                 val assertThatArgument = staticMethodCall.firstArg as? PsiMethodCallExpression ?: return
                 val mapping = MAPPINGS.firstOrNull { it.callMatcher.test(assertThatArgument) } ?: return
 
@@ -62,7 +59,9 @@ class AssertThatStringExpressionInspection : AbstractAssertJInspection() {
                 val expectedResult = expectedCallExpression.getAllTheSameExpectedBooleanConstants() ?: return
 
                 val replacementMethod = if (expectedResult) mapping.replacementForTrue else mapping.replacementForFalse
-                registerMoveOutMethod(holder, expectedCallExpression, assertThatArgument, replacementMethod, ::MoveOutMethodCallExpressionQuickFix)
+                registerMoveOutMethod(holder, expectedCallExpression, assertThatArgument, replacementMethod) { desc, method ->
+                    MoveOutMethodCallExpressionQuickFix(desc, method)
+                }
             }
         }
     }

src/main/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatStringIsEmptyInspection.kt

@@ -5,6 +5,7 @@ import com.intellij.psi.JavaElementVisitor
 import com.intellij.psi.PsiElementVisitor
 import com.intellij.psi.PsiMethodCallExpression
 import com.intellij.psi.PsiStatement
+import com.siyeh.ig.callMatcher.CallMatcher
 import de.platon42.intellij.plugins.cajon.AssertJClassNames.Companion.ABSTRACT_CHAR_SEQUENCE_ASSERT_CLASSNAME
 import de.platon42.intellij.plugins.cajon.MethodNames
 import de.platon42.intellij.plugins.cajon.calculateConstantParameterValue
@@ -22,19 +23,13 @@ class AssertThatStringIsEmptyInspection : AbstractAssertJInspection() {
         return object : JavaElementVisitor() {
             override fun visitMethodCallExpression(expression: PsiMethodCallExpression) {
                 super.visitMethodCallExpression(expression)
-                if (!expression.hasAssertThat()) {
-                    return
-                }
-                val isEqual = IS_EQUAL_TO_OBJECT.test(expression)
+                if (!expression.hasAssertThat()) return
+                val isEqual = CallMatcher.anyOf(IS_EQUAL_TO_OBJECT, IS_EQUAL_TO_STRING).test(expression)
                 val hasSize = HAS_SIZE.test(expression)
                 val isLastExpression = expression.parent is PsiStatement
-                if (!((isEqual || hasSize) && isLastExpression)) {
-                    return
-                }
+                if (!((isEqual || hasSize) && isLastExpression)) return
 
-                if (!checkAssertedType(expression, ABSTRACT_CHAR_SEQUENCE_ASSERT_CLASSNAME)) {
-                    return
-                }
+                if (!checkAssertedType(expression, ABSTRACT_CHAR_SEQUENCE_ASSERT_CLASSNAME)) return
 
                 val value = expression.calculateConstantParameterValue(0) ?: return
                 if ((isEqual && (value == "")) || (hasSize && (value == 0))) {

src/main/java/de/platon42/intellij/plugins/cajon/inspections/AssumeThatInsteadOfReturnInspection.kt

@@ -15,7 +15,7 @@ class AssumeThatInsteadOfReturnInspection : AbstractAssertJInspection() {
         private const val MAX_RECURSION_DEPTH = 5
         private const val MAX_STATEMENTS_COUNT = 50
 
-        private val TEST_ANNOTATIONS = listOf(
+        private val TEST_ANNOTATIONS = setOf(
             "org.junit.Test",
             "org.junit.jupiter.api.Test",
             "org.junit.jupiter.api.TestTemplate",
@@ -52,9 +52,9 @@ class AssumeThatInsteadOfReturnInspection : AbstractAssertJInspection() {
         return object : JavaElementVisitor() {
             override fun visitMethod(method: PsiMethod) {
                 super.visitMethod(method)
-                if (TEST_ANNOTATIONS.none(method::hasAnnotation)) {
-                    return
-                }
+                // Note: replace with if(TEST_ANNOTATIONS.none(method::hasAnnotation)) for IDEA >= 2018.2
+                val annotations = method.annotations.mapNotNull { it.qualifiedName }
+                if (annotations.none(TEST_ANNOTATIONS::contains)) return
                 val containingClass = method.containingClass ?: return
                 val visitor: PsiElementVisitor = TestMethodVisitor(holder, isOnTheFly, containingClass)
                 method.accept(visitor)
@@ -117,9 +117,7 @@ class AssumeThatInsteadOfReturnInspection : AbstractAssertJInspection() {
         var aborted = false
 
         override fun visitExpressionStatement(statement: PsiExpressionStatement) {
-            if (foundAssertThat || aborted) {
-                return
-            }
+            if (foundAssertThat || aborted) return
             if (++statementCount > MAX_STATEMENTS_COUNT) {
                 aborted = true
                 return

src/main/java/de/platon42/intellij/plugins/cajon/inspections/ImplicitAssertionInspection.kt

@@ -0,0 +1,130 @@
+package de.platon42.intellij.plugins.cajon.inspections
+
+import com.intellij.codeInspection.ProblemsHolder
+import com.intellij.openapi.util.TextRange
+import com.intellij.psi.JavaElementVisitor
+import com.intellij.psi.PsiElementVisitor
+import com.intellij.psi.PsiMethodCallExpression
+import com.siyeh.ig.callMatcher.CallMatcher
+import de.platon42.intellij.plugins.cajon.*
+import de.platon42.intellij.plugins.cajon.quickfixes.DeleteMethodCallQuickFix
+
+class ImplicitAssertionInspection : AbstractAssertJInspection() {
+
+    companion object {
+        private const val DISPLAY_NAME = "Asserting implicitly covered conditions"
+        private const val DELETE_IMPLICIT_DESCRIPTION_TEMPLATE = "Delete implicit %s() covered by %s()"
+        private const val SURPLUS_ASSERTION_MESSAGE = "Implicit %s() assertion is covered by %s()"
+
+        private val IS_PRESENT = CallMatcher.instanceCall(AssertJClassNames.ABSTRACT_OPTIONAL_ASSERT_CLASSNAME, MethodNames.IS_PRESENT, MethodNames.IS_NOT_EMPTY)
+            .parameterCount(0)!!
+        private val IS_NOT_PRESENT = CallMatcher.instanceCall(AssertJClassNames.ABSTRACT_OPTIONAL_ASSERT_CLASSNAME, MethodNames.IS_NOT_PRESENT, MethodNames.IS_EMPTY)
+            .parameterCount(0)!!
+        private val OPTIONAL_CONTAINS =
+            CallMatcher.instanceCall(
+                AssertJClassNames.ABSTRACT_OPTIONAL_ASSERT_CLASSNAME,
+                MethodNames.CONTAINS, MethodNames.CONTAINS_SAME,
+                "hasValue", "hasValueSatisfying", "containsInstanceOf"
+            ).parameterCount(1)!!
+
+        private val OBJECT_ENUMERABLE_ANY_CONTENT_ASSERTIONS = CallMatcher.instanceCall(
+            AssertJClassNames.OBJECT_ENUMERABLE_ASSERT_INTERFACE,
+            MethodNames.CONTAINS, "containsOnly", "containsOnlyNulls", MethodNames.CONTAINS_ONLY_ONCE,
+            "containsExactly", "containsExactlyInAnyOrder", "containsExactlyInAnyOrderElementsOf",
+            "containsAll", "containsAnyOf",
+            "containsAnyElementsOf", "containsExactlyElementsOf", "containsOnlyElementsOf",
+            "isSubsetOf", "containsSequence", "containsSubsequence",
+            "doesNotContainSequence", "doesNotContainSubsequence", "doesNotContain",
+            "doesNotContainAnyElementsOf", "doesNotHaveDuplicates",
+            "startsWith", "endsWith", "containsNull", "doesNotContainNull",
+            "are", "areNot", "have", "doNotHave", "areAtLeastOne", "areAtLeast", "areAtMost", "areExactly",
+            "haveAtLeastOne", "haveAtLeast", "haveAtMost", "haveExactly",
+            "doesNotHave", "doesNotHaveSameClassAs",
+            "hasAtLeastOneElementOfType", "hasOnlyElementsOfType", "hasOnlyElementsOfTypes",
+            "doesNotHaveAnyElementsOfTypes",
+            "has", "doesNotHave",
+            "hasOnlyOneElementSatisfying", "hasSameElementsAs",
+            "allMatch", "allSatisfy", "anyMatch", "anySatisfy", "noneMatch", "noneSatisfy"
+        )!!
+
+        private val OBJECT_ENUMERABLE_AT_LEAST_ONE_CONTENT_ASSERTIONS = CallMatcher.instanceCall(
+            AssertJClassNames.OBJECT_ENUMERABLE_ASSERT_INTERFACE,
+            "containsOnlyNulls",
+            "startsWith", "endsWith", "containsNull",
+            "areAtLeastOne",
+            "haveAtLeastOne",
+            "hasAtLeastOneElementOfType",
+            "anyMatch", "anySatisfy"
+        )!!
+
+        private val ENUMERABLE_NON_NULL_ASSERTIONS = CallMatcher.instanceCall(
+            AssertJClassNames.ENUMERABLE_ASSERT_INTERFACE,
+            MethodNames.IS_EMPTY, MethodNames.IS_NOT_EMPTY,
+            MethodNames.HAS_SIZE, MethodNames.HAS_SIZE_GREATER_THAN, MethodNames.HAS_SIZE_GREATER_THAN_OR_EQUAL_TO,
+            MethodNames.HAS_SIZE_LESS_THAN, MethodNames.HAS_SIZE_LESS_THAN_OR_EQUAL_TO,
+            "hasSizeBetween", MethodNames.HAS_SAME_SIZE_AS
+        )!!
+
+        private val ENUMERABLE_AT_LEAST_ONE_CONTENT_ASSERTIONS = CallMatcher.instanceCall(
+            AssertJClassNames.ENUMERABLE_ASSERT_INTERFACE,
+            MethodNames.HAS_SIZE, MethodNames.HAS_SIZE_GREATER_THAN,
+            MethodNames.HAS_SAME_SIZE_AS
+        )!!
+
+        private val NON_NULL_CORE_ASSERTIONS = CallMatcher.instanceCall(
+            AssertJClassNames.ASSERT_INTERFACE,
+            "isInstanceOf", "isInstanceOfSatisfying", "isInstanceOfAny", "isExactlyInstanceOf", "isOfAnyClassIn",
+            "isNotInstanceOf", "isNotInstanceOfAny", "isNotExactlyInstanceOf", "isNotOfAnyClassIn",
+            "hasSameClassAs", "doesNotHaveSameClassAs",
+            "hasToString", "hasSameHashCodeAs"
+        )!!
+
+        private val GUAVA_IS_PRESENT = CallMatcher.instanceCall(AssertJClassNames.GUAVA_OPTIONAL_ASSERTIONS_CLASSNAME, MethodNames.IS_PRESENT)
+            .parameterCount(0)!!
+        private val GUAVA_IS_ABSENT = CallMatcher.instanceCall(AssertJClassNames.GUAVA_OPTIONAL_ASSERTIONS_CLASSNAME, MethodNames.IS_ABSENT)
+            .parameterCount(0)!!
+        private val GUAVA_OPTIONAL_CONTAINS = CallMatcher.instanceCall(
+            AssertJClassNames.GUAVA_OPTIONAL_ASSERTIONS_CLASSNAME,
+            MethodNames.CONTAINS, "extractingValue", "extractingCharSequence"
+        )!!
+
+        private val MAPPINGS = listOf(
+            IS_NOT_NULL to CallMatcher.anyOf(
+                NON_NULL_CORE_ASSERTIONS,
+                ENUMERABLE_NON_NULL_ASSERTIONS,
+                OBJECT_ENUMERABLE_ANY_CONTENT_ASSERTIONS,
+                IS_PRESENT, IS_NOT_PRESENT, OPTIONAL_CONTAINS,
+                GUAVA_IS_PRESENT, GUAVA_IS_ABSENT, GUAVA_OPTIONAL_CONTAINS
+            )!!,
+
+            IS_NOT_EMPTY to CallMatcher.anyOf(
+                ENUMERABLE_AT_LEAST_ONE_CONTENT_ASSERTIONS,
+                OBJECT_ENUMERABLE_AT_LEAST_ONE_CONTENT_ASSERTIONS
+            )!!,
+
+            IS_PRESENT to OPTIONAL_CONTAINS,
+            GUAVA_IS_PRESENT to GUAVA_OPTIONAL_CONTAINS
+        )
+    }
+
+    override fun getDisplayName() = DISPLAY_NAME
+
+    override fun buildVisitor(holder: ProblemsHolder, isOnTheFly: Boolean): PsiElementVisitor {
+        return object : JavaElementVisitor() {
+            override fun visitMethodCallExpression(expression: PsiMethodCallExpression) {
+                super.visitMethodCallExpression(expression)
+                if (!expression.hasAssertThat()) return
+
+                val mapping = MAPPINGS.firstOrNull { it.first.test(expression) } ?: return
+                val followupExpression = expression.findFluentCallTo(mapping.second) ?: return
+                val redundantName = getOriginalMethodName(expression) ?: return
+                val followupName = getOriginalMethodName(followupExpression) ?: return
+                val description = DELETE_IMPLICIT_DESCRIPTION_TEMPLATE.format(redundantName, followupName)
+                val quickFix = DeleteMethodCallQuickFix(description)
+
+                val textRange = TextRange(expression.qualifierExpression.textLength, expression.textLength)
+                holder.registerProblem(expression, textRange, SURPLUS_ASSERTION_MESSAGE.format(redundantName, followupName), quickFix)
+            }
+        }
+    }
+}

src/main/java/de/platon42/intellij/plugins/cajon/inspections/JUnitAssertToAssertJInspection.kt

@@ -10,43 +10,44 @@ import com.siyeh.ig.callMatcher.CallMatcher.staticCall
 import de.platon42.intellij.plugins.cajon.AssertJClassNames
 import de.platon42.intellij.plugins.cajon.MethodNames
 import de.platon42.intellij.plugins.cajon.quickfixes.ReplaceJUnitAssertMethodCallQuickFix
+import de.platon42.intellij.plugins.cajon.quickfixes.ReplaceJUnitAssumeMethodCallQuickFix
 import de.platon42.intellij.plugins.cajon.quickfixes.ReplaceJUnitDeltaAssertMethodCallQuickFix
 
 class JUnitAssertToAssertJInspection : AbstractJUnitAssertInspection() {
 
     companion object {
-        private const val DISPLAY_NAME = "Convert JUnit assertions to AssertJ"
+        private const val DISPLAY_NAME = "Convert JUnit assertions/assumptions to AssertJ"
         private const val CONVERT_MESSAGE_TEMPLATE = "%s can be converted to AssertJ style"
-        private const val CONVERT_DESCRIPTION_TEMPLATE = "Convert %s() to assertThat().%s()"
+        private const val CONVERT_DESCRIPTION_TEMPLATE = "Convert %s() to %s().%s()"
 
-        private val MAPPINGS = listOf(
+        private val ASSERT_MAPPINGS = listOf(
             Mapping(
                 anyOf(
                     staticCall(JUNIT_ASSERT_CLASSNAME, ASSERT_TRUE_METHOD).parameterTypes(CommonClassNames.JAVA_LANG_STRING, "boolean"),
                     staticCall(JUNIT_ASSERT_CLASSNAME, ASSERT_TRUE_METHOD).parameterTypes("boolean")
                 ),
-                MethodNames.IS_TRUE, false
+                MethodNames.IS_TRUE, hasExpected = false
             ),
             Mapping(
                 anyOf(
                     staticCall(JUNIT_ASSERT_CLASSNAME, ASSERT_FALSE_METHOD).parameterTypes(CommonClassNames.JAVA_LANG_STRING, "boolean"),
                     staticCall(JUNIT_ASSERT_CLASSNAME, ASSERT_FALSE_METHOD).parameterTypes("boolean")
                 ),
-                MethodNames.IS_FALSE, false
+                MethodNames.IS_FALSE, hasExpected = false
             ),
             Mapping(
                 anyOf(
                     staticCall(JUNIT_ASSERT_CLASSNAME, ASSERT_NULL_METHOD).parameterTypes(CommonClassNames.JAVA_LANG_STRING, CommonClassNames.JAVA_LANG_OBJECT),
                     staticCall(JUNIT_ASSERT_CLASSNAME, ASSERT_NULL_METHOD).parameterTypes(CommonClassNames.JAVA_LANG_OBJECT)
                 ),
-                MethodNames.IS_NULL, false
+                MethodNames.IS_NULL, hasExpected = false
             ),
             Mapping(
                 anyOf(
                     staticCall(JUNIT_ASSERT_CLASSNAME, ASSERT_NOT_NULL_METHOD).parameterTypes(CommonClassNames.JAVA_LANG_STRING, CommonClassNames.JAVA_LANG_OBJECT),
                     staticCall(JUNIT_ASSERT_CLASSNAME, ASSERT_NOT_NULL_METHOD).parameterTypes(CommonClassNames.JAVA_LANG_OBJECT)
                 ),
-                MethodNames.IS_NOT_NULL, false
+                MethodNames.IS_NOT_NULL, hasExpected = false
             ),
             Mapping(
                 anyOf(
@@ -111,6 +112,34 @@ class JUnitAssertToAssertJInspection : AbstractJUnitAssertInspection() {
                 MethodNames.CONTAINS_EXACTLY
             )
         )
+
+        private val ASSUME_MAPPINGS = listOf(
+            Mapping(
+                anyOf(
+                    staticCall(JUNIT_ASSUME_CLASSNAME, ASSUME_TRUE_METHOD).parameterTypes(CommonClassNames.JAVA_LANG_STRING, "boolean"),
+                    staticCall(JUNIT_ASSUME_CLASSNAME, ASSUME_TRUE_METHOD).parameterTypes("boolean")
+                ),
+                MethodNames.IS_TRUE, hasExpected = false
+            ),
+            Mapping(
+                anyOf(
+                    staticCall(JUNIT_ASSUME_CLASSNAME, ASSUME_FALSE_METHOD).parameterTypes(CommonClassNames.JAVA_LANG_STRING, "boolean"),
+                    staticCall(JUNIT_ASSUME_CLASSNAME, ASSUME_FALSE_METHOD).parameterTypes("boolean")
+                ),
+                MethodNames.IS_FALSE, hasExpected = false
+            ),
+            Mapping(
+                staticCall(JUNIT_ASSUME_CLASSNAME, ASSUME_NOT_NULL_METHOD).parameterCount(1),
+                MethodNames.IS_NOT_NULL, hasExpected = false, singleArgument = true
+            ),
+            Mapping(
+                anyOf(
+                    staticCall(JUNIT_ASSUME_CLASSNAME, ASSUME_NO_EXCEPTION).parameterTypes(CommonClassNames.JAVA_LANG_STRING, CommonClassNames.JAVA_LANG_THROWABLE),
+                    staticCall(JUNIT_ASSUME_CLASSNAME, ASSUME_NO_EXCEPTION).parameterTypes(CommonClassNames.JAVA_LANG_THROWABLE)
+                ),
+                "doesNotThrowAnyException", hasExpected = false
+            )
+        )
     }
 
     override fun getDisplayName() = DISPLAY_NAME
@@ -119,21 +148,31 @@ class JUnitAssertToAssertJInspection : AbstractJUnitAssertInspection() {
         return object : JavaElementVisitor() {
             override fun visitMethodCallExpression(expression: PsiMethodCallExpression) {
                 super.visitMethodCallExpression(expression)
-                val isJUnitAssertCall = expression.resolveMethod()?.containingClass?.qualifiedName == JUNIT_ASSERT_CLASSNAME
-                if (!isJUnitAssertCall) {
-                    return // early exit
-                }
+                when (expression.resolveMethod()?.containingClass?.qualifiedName) {
+                    JUNIT_ASSERT_CLASSNAME -> {
                         JavaPsiFacade.getInstance(expression.project)
                             .findClass(AssertJClassNames.ASSERTIONS_CLASSNAME, GlobalSearchScope.allScope(expression.project)) ?: return
-                val mapping = MAPPINGS.firstOrNull { it.callMatcher.test(expression) } ?: return
+                        val mapping = ASSERT_MAPPINGS.firstOrNull { it.callMatcher.test(expression) } ?: return
                         if (mapping.hasDelta) {
-                    registerConvertMethod(holder, expression, mapping.replacement, ::ReplaceJUnitDeltaAssertMethodCallQuickFix)
+                            registerConvertMethod(holder, expression, mapping.replacement, MethodNames.ASSERT_THAT, ::ReplaceJUnitDeltaAssertMethodCallQuickFix)
                         } else {
-                    registerConvertMethod(holder, expression, mapping.replacement) { desc, method ->
+                            registerConvertMethod(holder, expression, mapping.replacement, MethodNames.ASSERT_THAT) { desc, method ->
                                 ReplaceJUnitAssertMethodCallQuickFix(desc, method, !mapping.hasExpected)
                             }
                         }
                     }
+                    JUNIT_ASSUME_CLASSNAME -> {
+                        JavaPsiFacade.getInstance(expression.project)
+                            .findClass(AssertJClassNames.ASSUMPTIONS_CLASSNAME, GlobalSearchScope.allScope(expression.project)) ?: return
+                        val mapping = ASSUME_MAPPINGS.firstOrNull { it.callMatcher.test(expression) } ?: return
+                        if (!mapping.singleArgument || expression.argumentList.expressions.size == 1) {
+                            registerConvertMethod(holder, expression, mapping.replacement, MethodNames.ASSUME_THAT) { desc, method ->
+                                ReplaceJUnitAssumeMethodCallQuickFix(desc, method)
+                            }
+                        }
+                    }
+                }
+            }
         }
     }
 
@@ -141,10 +180,11 @@ class JUnitAssertToAssertJInspection : AbstractJUnitAssertInspection() {
         holder: ProblemsHolder,
         expression: PsiMethodCallExpression,
         replacementMethod: String,
+        staticMethod: String,
         quickFixSupplier: (String, String) -> LocalQuickFix
     ) {
         val originalMethod = getOriginalMethodName(expression) ?: return
-        val description = CONVERT_DESCRIPTION_TEMPLATE.format(originalMethod, replacementMethod)
+        val description = CONVERT_DESCRIPTION_TEMPLATE.format(originalMethod, staticMethod, replacementMethod)
         val message = CONVERT_MESSAGE_TEMPLATE.format(originalMethod)
         val quickfix = quickFixSupplier(description, replacementMethod)
         holder.registerProblem(expression, message, quickfix)
@@ -154,6 +194,7 @@ class JUnitAssertToAssertJInspection : AbstractJUnitAssertInspection() {
         val callMatcher: CallMatcher,
         val replacement: String,
         val hasExpected: Boolean = true,
-        val hasDelta: Boolean = false
+        val hasDelta: Boolean = false,
+        val singleArgument: Boolean = false
     )
 }

src/main/java/de/platon42/intellij/plugins/cajon/inspections/JoinAssertThatStatementsInspection.kt

@@ -2,19 +2,25 @@ package de.platon42.intellij.plugins.cajon.inspections
 
 import com.intellij.codeInspection.ProblemHighlightType
 import com.intellij.codeInspection.ProblemsHolder
+import com.intellij.codeInspection.ui.SingleIntegerFieldOptionsPanel
 import com.intellij.psi.*
 import com.intellij.psi.util.PsiTreeUtil
-import com.siyeh.ig.psiutils.TrackingEquivalenceChecker
+import com.siyeh.ig.psiutils.EquivalenceChecker
 import de.platon42.intellij.plugins.cajon.*
 import de.platon42.intellij.plugins.cajon.quickfixes.JoinStatementsQuickFix
+import javax.swing.JComponent
 
 class JoinAssertThatStatementsInspection : AbstractAssertJInspection() {
 
     companion object {
         private const val DISPLAY_NAME = "Join multiple assertThat() statements with same actual expression"
         private const val CAN_BE_JOINED_DESCRIPTION = "Multiple assertThat() statements can be joined together"
+        private const val DEFAULT_SEPARATE_LINE_LIMIT = 1
     }
 
+    @JvmField
+    var separateLineLimit: Int = DEFAULT_SEPARATE_LINE_LIMIT
+
     override fun getDisplayName() = DISPLAY_NAME
 
     override fun buildVisitor(holder: ProblemsHolder, isOnTheFly: Boolean): PsiElementVisitor {
@@ -25,7 +31,8 @@ class JoinAssertThatStatementsInspection : AbstractAssertJInspection() {
                 var sameCount = 0
                 var firstStatement: PsiStatement? = null
                 var lastStatement: PsiStatement? = null
-                val equivalenceChecker = TrackingEquivalenceChecker()
+                // Note: replace with TrackingEquivalenceChecker() for IDEA >= 2019.1
+                val equivalenceChecker = EquivalenceChecker.getCanonicalPsiEquivalence()!!
                 for (statement in block.statements) {
                     val assertThatCall = isLegitAssertThatCall(statement)
                     var reset = true
@@ -34,15 +41,9 @@ class JoinAssertThatStatementsInspection : AbstractAssertJInspection() {
                         reset = (lastActualExpression == null)
                         actualExpression = assertThatCall.firstArg
                         if (!reset) {
-                            val isSame = when (actualExpression) {
-                                is PsiMethodCallExpression -> equivalenceChecker.expressionsAreEquivalent(actualExpression, lastActualExpression)
-                                        && PsiTreeUtil.findChildrenOfAnyType(
-                                    actualExpression,
-                                    false,
-                                    PsiMethodCallExpression::class.java
-                                ).none { KNOWN_METHODS_WITH_SIDE_EFFECTS.test(it) }
-                                else -> equivalenceChecker.expressionsAreEquivalent(actualExpression, lastActualExpression)
-                            }
+                            val isSame = equivalenceChecker.expressionsAreEquivalent(actualExpression, lastActualExpression)
+                                    && !hasExpressionWithSideEffects(actualExpression)
+
                             if (isSame) {
                                 sameCount++
                                 lastStatement = statement
@@ -68,15 +69,37 @@ class JoinAssertThatStatementsInspection : AbstractAssertJInspection() {
 
             private fun isLegitAssertThatCall(statement: PsiStatement?): PsiMethodCallExpression? {
                 if ((statement is PsiExpressionStatement) && (statement.expression is PsiMethodCallExpression)) {
-                    if (!statement.hasAssertThat()) {
-                        return null
-                    }
+                    if (!statement.hasAssertThat()) return null
+
                     val assertThatCall = PsiTreeUtil.findChildrenOfType(statement, PsiMethodCallExpression::class.java).find { ALL_ASSERT_THAT_MATCHERS.test(it) }
                     return assertThatCall?.takeIf { it.findFluentCallTo(EXTRACTING_CALL_MATCHERS) == null }
                 }
                 return null
             }
+
+            private fun hasExpressionWithSideEffects(actualExpression: PsiExpression): Boolean {
+                var result = false
+                PsiTreeUtil.processElements(actualExpression) { element ->
+                    val matched = when (element) {
+                        is PsiUnaryExpression -> (element.operationTokenType == JavaTokenType.PLUSPLUS)
+                                || (element.operationTokenType == JavaTokenType.MINUSMINUS)
+                        is PsiMethodCallExpression -> KNOWN_METHODS_WITH_SIDE_EFFECTS.test(element)
+                        else -> false
                     }
+                    if (matched) {
+                        result = true
+                        false
+                    } else {
+                        true
+                    }
+                }
+                return result
+            }
+        }
+    }
+
+    override fun createOptionsPanel(): JComponent {
+        return SingleIntegerFieldOptionsPanel("Limit for joins before adding line breaks:", this, "separateLineLimit")
     }
 
     private fun registerProblem(holder: ProblemsHolder, isOnTheFly: Boolean, firstStatement: PsiStatement, lastStatement: PsiStatement) {
@@ -86,7 +109,7 @@ class JoinAssertThatStatementsInspection : AbstractAssertJInspection() {
             CAN_BE_JOINED_DESCRIPTION,
             ProblemHighlightType.GENERIC_ERROR_OR_WARNING,
             isOnTheFly,
-            JoinStatementsQuickFix()
+            JoinStatementsQuickFix(separateLineLimit)
         )
         holder.registerProblem(problemDescriptor)
     }

src/main/java/de/platon42/intellij/plugins/cajon/inspections/JoinVarArgsContainsInspection.kt

@@ -0,0 +1,53 @@
+package de.platon42.intellij.plugins.cajon.inspections
+
+import com.intellij.codeInspection.ProblemsHolder
+import com.intellij.openapi.util.TextRange
+import com.intellij.psi.JavaElementVisitor
+import com.intellij.psi.PsiElementVisitor
+import com.intellij.psi.PsiExpressionStatement
+import com.intellij.psi.PsiMethodCallExpression
+import com.intellij.psi.util.PsiTreeUtil
+import com.siyeh.ig.callMatcher.CallMatcher
+import de.platon42.intellij.plugins.cajon.*
+import de.platon42.intellij.plugins.cajon.quickfixes.JoinVarArgsContainsQuickFix
+
+class JoinVarArgsContainsInspection : AbstractAssertJInspection() {
+
+    companion object {
+        private const val DISPLAY_NAME = "Join variadic arguments of contains()/containsOnlyOnce()/doesNotContain()"
+        private const val JOIN_VARARGS_MESSAGE = "Calls to same methods may be joined to variadic version"
+
+        private val MATCHERS = listOf(MethodNames.CONTAINS, MethodNames.CONTAINS_ONLY_ONCE, MethodNames.DOES_NOT_CONTAIN)
+            .map { CallMatcher.instanceCall(AssertJClassNames.ABSTRACT_ITERABLE_ASSERT_CLASSNAME, it) }
+    }
+
+    override fun getDisplayName() = DISPLAY_NAME
+
+    override fun buildVisitor(holder: ProblemsHolder, isOnTheFly: Boolean): PsiElementVisitor {
+        return object : JavaElementVisitor() {
+            override fun visitExpressionStatement(statement: PsiExpressionStatement) {
+                super.visitStatement(statement)
+                if (!statement.hasAssertThat()) return
+                val assertThatCall = PsiTreeUtil.findChildrenOfType(statement, PsiMethodCallExpression::class.java).find { ALL_ASSERT_THAT_MATCHERS.test(it) } ?: return
+
+                val allCalls = assertThatCall.collectMethodCallsUpToStatement().toList()
+
+                if (allCalls.find(COMPLEX_CALLS_THAT_MAKES_STUFF_TRICKY::test) != null) return
+
+                val onlyAssertionCalls = allCalls
+                    .filterNot { NOT_ACTUAL_ASSERTIONS.test(it) }
+                    .toList()
+
+                for (methodMatcher in MATCHERS) {
+                    if (onlyAssertionCalls.count(methodMatcher::test) > 1) {
+                        val outmostMethodCall = statement.findOutmostMethodCall() ?: return
+                        val quickFix = JoinVarArgsContainsQuickFix(MATCHERS)
+                        val textRange = TextRange(outmostMethodCall.qualifierExpression.textLength, outmostMethodCall.textLength)
+                        holder.registerProblem(outmostMethodCall, textRange, JOIN_VARARGS_MESSAGE, quickFix)
+                        return
+                    }
+                }
+            }
+        }
+    }
+}

src/main/java/de/platon42/intellij/plugins/cajon/quickfixes/DeleteMethodCallQuickFix.kt

@@ -0,0 +1,23 @@
+package de.platon42.intellij.plugins.cajon.quickfixes
+
+import com.intellij.codeInspection.ProblemDescriptor
+import com.intellij.openapi.project.Project
+import com.intellij.psi.PsiMethodCallExpression
+import de.platon42.intellij.plugins.cajon.qualifierExpression
+
+class DeleteMethodCallQuickFix(description: String) : AbstractCommonQuickFix(description) {
+
+    companion object {
+        private const val DELETE_METHOD_DESCRIPTION = "Delete unnecessary method calls"
+    }
+
+    override fun getFamilyName(): String {
+        return DELETE_METHOD_DESCRIPTION
+    }
+
+    override fun applyFix(project: Project, descriptor: ProblemDescriptor) {
+        val methodCallExpression = descriptor.startElement as? PsiMethodCallExpression ?: return
+
+        methodCallExpression.replace(methodCallExpression.qualifierExpression)
+    }
+}

src/main/java/de/platon42/intellij/plugins/cajon/quickfixes/HasHashCodeQuickFix.kt

@@ -0,0 +1,37 @@
+package de.platon42.intellij.plugins.cajon.quickfixes
+
+import com.intellij.codeInspection.ProblemDescriptor
+import com.intellij.openapi.project.Project
+import com.intellij.psi.PsiMethodCallExpression
+import de.platon42.intellij.plugins.cajon.*
+
+class HasHashCodeQuickFix :
+    AbstractCommonQuickFix(HASHCODE_DESCRIPTION) {
+
+    companion object {
+        private const val HASHCODE_DESCRIPTION = "Replace calls to hashCode() with hasSameHashCodeAs()"
+    }
+
+    override fun getFamilyName(): String {
+        return HASHCODE_DESCRIPTION
+    }
+
+    override fun applyFix(project: Project, descriptor: ProblemDescriptor) {
+        val outmostCallExpression = descriptor.startElement as? PsiMethodCallExpression ?: return
+        val assertThatMethodCall = outmostCallExpression.findStaticMethodCall() ?: return
+
+        val assertExpression = assertThatMethodCall.firstArg as? PsiMethodCallExpression ?: return
+
+        val methodsToFix = assertThatMethodCall.gatherAssertionCalls()
+
+        assertExpression.replace(assertExpression.qualifierExpression)
+
+        methodsToFix
+            .forEach {
+                val innerHashCodeObject = (it.firstArg as PsiMethodCallExpression).qualifierExpression
+                val expectedExpression = createExpectedMethodCall(it, "hasSameHashCodeAs", innerHashCodeObject)
+                expectedExpression.replaceQualifierFromMethodCall(it)
+                it.replace(expectedExpression)
+            }
+    }
+}

src/main/java/de/platon42/intellij/plugins/cajon/quickfixes/JoinStatementsQuickFix.kt

@@ -7,7 +7,7 @@ import com.intellij.psi.util.PsiTreeUtil
 import de.platon42.intellij.plugins.cajon.findStaticMethodCall
 import de.platon42.intellij.plugins.cajon.shortenAndReformat
 
-class JoinStatementsQuickFix : AbstractCommonQuickFix(JOIN_STATEMENTS_MESSAGE) {
+class JoinStatementsQuickFix(private val separateLineLimit: Int) : AbstractCommonQuickFix(JOIN_STATEMENTS_MESSAGE) {
 
     companion object {
         private const val JOIN_STATEMENTS_MESSAGE = "Join assertThat() statements"
@@ -16,31 +16,35 @@ class JoinStatementsQuickFix : AbstractCommonQuickFix(JOIN_STATEMENTS_MESSAGE) {
     override fun applyFix(project: Project, descriptor: ProblemDescriptor) {
         val firstStatement = descriptor.startElement as PsiExpressionStatement
         val lastStatement = descriptor.endElement as PsiExpressionStatement
+
+        val expressionCount = countExpressions(firstStatement, lastStatement)
+        val addLineBreaks = (expressionCount > separateLineLimit)
+
         do {
             val commentsToKeep = ArrayList<PsiComment>()
             val stuffToDelete = ArrayList<PsiElement>()
-            var previousStatement = lastStatement.prevSibling ?: throw IllegalStateException("Internal error")
+            var previousStatement = lastStatement.prevSibling!!
             while (previousStatement !is PsiExpressionStatement) {
                 if (previousStatement is PsiComment) {
                     commentsToKeep.add(previousStatement.copy() as PsiComment)
                 }
                 stuffToDelete.add(previousStatement)
-                previousStatement = previousStatement.prevSibling ?: throw IllegalStateException("Internal error")
+                previousStatement = previousStatement.prevSibling!!
             }
             stuffToDelete.forEach { if (it.isValid) it.delete() }
 
             val statementComments = PsiTreeUtil.getChildrenOfAnyType(previousStatement, PsiComment::class.java)
             commentsToKeep.addAll(statementComments)
 
-            val assertThatCallOfCursorStatement = lastStatement.findStaticMethodCall() ?: throw IllegalStateException("Internal error")
+            val assertThatCallOfCursorStatement = lastStatement.findStaticMethodCall()!!
 
             val lastElementBeforeConcat = assertThatCallOfCursorStatement.parent
             commentsToKeep.forEach {
                 lastElementBeforeConcat.addAfter(it, lastElementBeforeConcat.firstChild)
-                val newLineNode =
-                    PsiParserFacade.SERVICE.getInstance(project).createWhiteSpaceFromText("\n\t")
-
-                lastElementBeforeConcat.addAfter(newLineNode, lastElementBeforeConcat.firstChild)
+                addLineBreak(project, lastElementBeforeConcat)
+            }
+            if (commentsToKeep.isEmpty() && addLineBreaks) {
+                addLineBreak(project, lastElementBeforeConcat)
             }
 
             val newLeaf = previousStatement.firstChild
@@ -50,4 +54,27 @@ class JoinStatementsQuickFix : AbstractCommonQuickFix(JOIN_STATEMENTS_MESSAGE) {
         val codeBlock = PsiTreeUtil.getParentOfType(lastStatement, PsiCodeBlock::class.java) ?: return
         codeBlock.shortenAndReformat()
     }
+
+    private fun addLineBreak(project: Project, lastElementBeforeConcat: PsiElement) {
+        val newLineNode =
+            PsiParserFacade.SERVICE.getInstance(project).createWhiteSpaceFromText("\n\t")
+
+        lastElementBeforeConcat.addAfter(newLineNode, lastElementBeforeConcat.firstChild)
+    }
+
+    private fun countExpressions(firstStatement: PsiElement, lastStatement: PsiElement): Int {
+        var count = 0
+        var currentStatement = firstStatement
+        do {
+            while (currentStatement !is PsiExpressionStatement) {
+                currentStatement = currentStatement.nextSibling!!
+            }
+            count++
+            if (currentStatement === lastStatement) {
+                break
+            }
+            currentStatement = currentStatement.nextSibling!!
+        } while (true)
+        return count
+    }
 }

src/main/java/de/platon42/intellij/plugins/cajon/quickfixes/JoinVarArgsContainsQuickFix.kt

@@ -0,0 +1,38 @@
+package de.platon42.intellij.plugins.cajon.quickfixes
+
+import com.intellij.codeInspection.ProblemDescriptor
+import com.intellij.openapi.project.Project
+import com.intellij.psi.PsiMethodCallExpression
+import com.siyeh.ig.callMatcher.CallMatcher
+import de.platon42.intellij.plugins.cajon.*
+
+class JoinVarArgsContainsQuickFix(private val matchers: Iterable<CallMatcher>) : AbstractCommonQuickFix(JOIN_VARARGS_DESCRIPTION) {
+
+    companion object {
+        private const val JOIN_VARARGS_DESCRIPTION = "Join multiple arguments to variadic argument method calls"
+    }
+
+    override fun applyFix(project: Project, descriptor: ProblemDescriptor) {
+        var outmostCallExpression = descriptor.startElement as? PsiMethodCallExpression ?: return
+
+        for (matcher in matchers) {
+            val assertThatMethodCall = outmostCallExpression.findStaticMethodCall() ?: return
+            val methodsToFix = assertThatMethodCall.gatherAssertionCalls()
+            val matchedCalls = methodsToFix.filter(matcher::test)
+            if (matchedCalls.size > 1) {
+                val mainCall = matchedCalls.first()
+                val args = mutableListOf(*mainCall.argumentList.expressions)
+                for (secondaryCall in matchedCalls.asSequence().drop(1)) {
+                    args.addAll(secondaryCall.argumentList.expressions)
+                }
+                val newMainCall = createExpectedMethodCall(mainCall, mainCall.methodExpression.qualifiedName, *args.toTypedArray())
+                newMainCall.replaceQualifierFromMethodCall(mainCall)
+                mainCall.replace(newMainCall)
+                for (secondaryCall in matchedCalls.asSequence().drop(1)) {
+                    val newQualifier = secondaryCall.qualifierExpression
+                    outmostCallExpression = secondaryCall.replace(newQualifier).findOutmostMethodCall() ?: return
+                }
+            }
+        }
+    }
+}

src/main/java/de/platon42/intellij/plugins/cajon/quickfixes/MoveOutMethodCallExpressionQuickFix.kt

@@ -5,7 +5,13 @@ import com.intellij.openapi.project.Project
 import com.intellij.psi.PsiMethodCallExpression
 import de.platon42.intellij.plugins.cajon.*
 
-class MoveOutMethodCallExpressionQuickFix(description: String, private val replacementMethod: String) : AbstractCommonQuickFix(description) {
+class MoveOutMethodCallExpressionQuickFix(
+    description: String,
+    private val replacementMethod: String,
+    private val useNullNonNull: Boolean = false,
+    private val noExpectedExpression: Boolean = false
+) :
+    AbstractCommonQuickFix(description) {
 
     companion object {
         private const val REMOVE_ACTUAL_EXPRESSION_DESCRIPTION = "Move method calls in actual expressions out of assertThat()"
@@ -19,10 +25,10 @@ class MoveOutMethodCallExpressionQuickFix(description: String, private val repla
         val outmostCallExpression = descriptor.startElement as? PsiMethodCallExpression ?: return
         val assertThatMethodCall = outmostCallExpression.findStaticMethodCall() ?: return
         val assertExpression = assertThatMethodCall.firstArg as? PsiMethodCallExpression ?: return
-        val assertExpressionArg = assertExpression.getArgOrNull(0)?.copy()
+        val assertExpressionArg = if (noExpectedExpression) null else assertExpression.getArgOrNull(0)?.copy()
 
         val methodsToFix = assertThatMethodCall.collectMethodCallsUpToStatement()
-            .filter { it.getExpectedBooleanResult() != null }
+            .filter { (if (useNullNonNull) it.getExpectedNullNonNullResult() else it.getExpectedBooleanResult()) != null }
             .toList()
 
         assertExpression.replace(assertExpression.qualifierExpression)

src/main/java/de/platon42/intellij/plugins/cajon/quickfixes/ReplaceIfByAssumeThatQuickFix.kt

@@ -34,12 +34,14 @@ class ReplaceIfByAssumeThatQuickFix(private val removeElse: Boolean) : AbstractC
             val anchorElement = ifStatement.nextSibling
             if (branchToKeep is PsiBlockStatement) {
                 val codeBlock = branchToKeep.codeBlock
+                if (codeBlock.statements.isNotEmpty()) {
                     val hasDeclarations = codeBlock.statements.any { it is PsiDeclarationStatement }
                     if (hasDeclarations) {
                         parentBlock.addAfter(branchToKeep, anchorElement)
                     } else {
                         parentBlock.addRangeAfter(codeBlock.firstBodyElement, codeBlock.lastBodyElement, anchorElement)
                     }
+                }
             } else {
                 parentBlock.addAfter(branchToKeep, anchorElement)
             }

src/main/java/de/platon42/intellij/plugins/cajon/quickfixes/ReplaceJUnitAssertMethodCallQuickFix.kt

@@ -24,7 +24,7 @@ class ReplaceJUnitAssertMethodCallQuickFix(description: String, private val repl
         val args = methodCallExpression.argumentList
         val count = args.expressions.size
         val actualExpression = args.expressions[count - 1] ?: return
-        val (expectedExpression, messageExpression) = if (noExpectedExpression) {
+        val (expectedExpressions, messageExpression) = if (noExpectedExpression) {
             val message = args.expressions.getOrNull(count - 2)
             emptyArray<PsiExpression>() to message
         } else {
@@ -33,8 +33,15 @@ class ReplaceJUnitAssertMethodCallQuickFix(description: String, private val repl
             arrayOf(expected) to message
         }
 
-        val expectedMethodCall = createExpectedMethodCall(element, replacementMethod, *expectedExpression)
-        val newMethodCall = createAssertThat(element, actualExpression)
+        val swapActualAndExpected = ((expectedExpressions.getOrNull(0)?.calculateConstantValue() == null)
+                && (actualExpression.calculateConstantValue() != null))
+        val (expectedMethodCall, newMethodCall) = if (swapActualAndExpected) {
+            createExpectedMethodCall(element, replacementMethod, actualExpression) to
+                    createAssertThat(element, expectedExpressions.single())
+        } else {
+            createExpectedMethodCall(element, replacementMethod, *expectedExpressions) to
+                    createAssertThat(element, actualExpression)
+        }
 
         if (messageExpression != null) {
             val asExpression = createExpectedMethodCall(element, MethodNames.AS, messageExpression)

src/main/java/de/platon42/intellij/plugins/cajon/quickfixes/ReplaceJUnitAssumeMethodCallQuickFix.kt

@@ -0,0 +1,41 @@
+package de.platon42.intellij.plugins.cajon.quickfixes
+
+import com.intellij.codeInspection.ProblemDescriptor
+import com.intellij.openapi.project.Project
+import com.intellij.psi.PsiMethodCallExpression
+import de.platon42.intellij.plugins.cajon.*
+
+class ReplaceJUnitAssumeMethodCallQuickFix(description: String, private val replacementMethod: String) :
+    AbstractCommonQuickFix(description) {
+
+    companion object {
+        private const val CONVERT_DESCRIPTION = "Convert JUnit assumptions to assertJ"
+    }
+
+    override fun getFamilyName(): String {
+        return CONVERT_DESCRIPTION
+    }
+
+    override fun applyFix(project: Project, descriptor: ProblemDescriptor) {
+        val element = descriptor.startElement
+        val methodCallExpression = element as? PsiMethodCallExpression ?: return
+        val args = methodCallExpression.argumentList
+        val count = args.expressions.size
+        val actualExpression = args.expressions[count - 1] ?: return
+        val messageExpression = args.expressions.getOrNull(count - 2)
+
+        val expectedMethodCall = createExpectedMethodCall(element, replacementMethod)
+        val newMethodCall = createAssumeThat(element, actualExpression)
+
+        if (messageExpression != null) {
+            val asExpression = createExpectedMethodCall(element, MethodNames.AS, messageExpression)
+            asExpression.replaceQualifier(newMethodCall)
+            expectedMethodCall.replaceQualifier(asExpression)
+        } else {
+            expectedMethodCall.replaceQualifier(newMethodCall)
+        }
+
+        newMethodCall.resolveMethod()?.addAsStaticImport(element)
+        element.replace(expectedMethodCall).shortenAndReformat()
+    }
+}

src/main/java/de/platon42/intellij/plugins/cajon/quickfixes/ReplaceJUnitDeltaAssertMethodCallQuickFix.kt

@@ -9,7 +9,7 @@ import de.platon42.intellij.plugins.cajon.AssertJClassNames.Companion.GUAVA_ASSE
 class ReplaceJUnitDeltaAssertMethodCallQuickFix(description: String, private val replacementMethod: String) : AbstractCommonQuickFix(description) {
 
     companion object {
-        private const val CONVERT_DESCRIPTION = "Convert JUnit assertions to assertJ"
+        private const val CONVERT_DESCRIPTION = "Convert JUnit assertions with delta to assertJ"
     }
 
     override fun getFamilyName(): String {
@@ -27,8 +27,16 @@ class ReplaceJUnitDeltaAssertMethodCallQuickFix(description: String, private val
         val deltaExpression = args.expressions[count - 1] ?: return
 
         val offsetMethodCall = createMethodCall(element, "org.assertj.core.data.Offset.offset", deltaExpression)
-        val expectedMethodCall = createExpectedMethodCall(element, replacementMethod, expectedExpression, offsetMethodCall)
-        val newMethodCall = createAssertThat(element, actualExpression)
+
+        val swapActualAndExpected = ((expectedExpression.calculateConstantValue() == null)
+                && (actualExpression.calculateConstantValue() != null))
+        val (expectedMethodCall, newMethodCall) = if (swapActualAndExpected) {
+            createExpectedMethodCall(element, replacementMethod, actualExpression, offsetMethodCall) to
+                    createAssertThat(element, expectedExpression)
+        } else {
+            createExpectedMethodCall(element, replacementMethod, expectedExpression, offsetMethodCall) to
+                    createAssertThat(element, actualExpression)
+        }
 
         if (messageExpression != null) {
             val asExpression = createExpectedMethodCall(element, MethodNames.AS, messageExpression)

src/main/java/de/platon42/intellij/plugins/cajon/references/ExtractorReferenceContributor.kt

@@ -56,12 +56,10 @@ class ExtractorReferenceContributor : PsiReferenceContributor() {
 
         private fun findAndCreateReferences(element: PsiElement, finder: (PsiLiteralExpression) -> List<Pair<TextRange, List<PsiElement>>>?): Array<PsiReference> {
             val literal = element as PsiLiteralExpression
-            val results = finder(literal)
-            if (results != null) {
+            val results = finder(literal) ?: return PsiReference.EMPTY_ARRAY
+
             return results.map { ExtractorReference(literal, it.first, it.second) }.toTypedArray()
         }
-            return PsiReference.EMPTY_ARRAY
-        }
     }
 
     override fun registerReferenceProviders(registrar: PsiReferenceRegistrar) {
@@ -73,6 +71,7 @@ class ExtractorReferenceContributor : PsiReferenceContributor() {
     class ExtractorReference(literal: PsiLiteralExpression, range: TextRange, private val targets: List<PsiElement>) :
         PsiPolyVariantReferenceBase<PsiLiteralExpression>(literal, range, true) {
 
+        // Do not remove due to compatiblity issue with IDEA <= 2018.2
         override fun getVariants(): Array<Any> {
             return ArrayUtil.EMPTY_OBJECT_ARRAY
         }
@@ -88,9 +87,7 @@ class ExtractorReferenceContributor : PsiReferenceContributor() {
 
     class PropertyOrFieldReferenceProvider : PsiReferenceProvider() {
 
-        override fun getReferencesByElement(element: PsiElement, context: ProcessingContext): Array<PsiReference> {
-            return findAndCreateReferences(element, ::findReferences)
-        }
+        override fun getReferencesByElement(element: PsiElement, context: ProcessingContext): Array<PsiReference> = findAndCreateReferences(element, ::findReferences)
 
         fun findReferences(element: PsiLiteralExpression): List<Pair<TextRange, List<PsiElement>>>? {
             val literal = element.value as? String ?: return null
@@ -112,9 +109,7 @@ class ExtractorReferenceContributor : PsiReferenceContributor() {
 
     class IterablePropertyOrFieldReferenceProvider : PsiReferenceProvider() {
 
-        override fun getReferencesByElement(element: PsiElement, context: ProcessingContext): Array<PsiReference> {
-            return findAndCreateReferences(element, ::findReferences)
-        }
+        override fun getReferencesByElement(element: PsiElement, context: ProcessingContext): Array<PsiReference> = findAndCreateReferences(element, ::findReferences)
 
         fun findReferences(element: PsiLiteralExpression): List<Pair<TextRange, List<PsiElement>>>? {
             val literal = element.value as? String ?: return null
@@ -127,9 +122,8 @@ class ExtractorReferenceContributor : PsiReferenceContributor() {
                 isResultOf = true
             }
 
-            if (!CallMatcher.anyOf(EXTRACTING_FROM_ITERABLE, FLAT_EXTRACTING_FROM_ITERABLE).test(methodCallExpression)) {
-                return null
-            }
+            if (!CallMatcher.anyOf(EXTRACTING_FROM_ITERABLE, FLAT_EXTRACTING_FROM_ITERABLE).test(methodCallExpression)) return null
+
             val iterableType = findActualType(methodCallExpression) ?: return null
             val innerType = iterableType.resolveGenerics().substitutor.substitute(iterableType.parameters[0])
             val containingClass = PsiTypesUtil.getPsiClass(innerType) ?: return null
@@ -139,16 +133,13 @@ class ExtractorReferenceContributor : PsiReferenceContributor() {
 
     class IterableResultOfReferenceProvider : PsiReferenceProvider() {
 
-        override fun getReferencesByElement(element: PsiElement, context: ProcessingContext): Array<PsiReference> {
-            return findAndCreateReferences(element, ::findReferences)
-        }
+        override fun getReferencesByElement(element: PsiElement, context: ProcessingContext): Array<PsiReference> = findAndCreateReferences(element, ::findReferences)
 
         fun findReferences(element: PsiLiteralExpression): List<Pair<TextRange, List<PsiElement>>>? {
             val literal = element.value as? String ?: return null
             val methodCallExpression = PsiTreeUtil.getParentOfType(element, PsiMethodCallExpression::class.java) ?: return null
-            if (!EXTRACTING_RESULT_OF_FROM_ITERABLE.test(methodCallExpression)) {
-                return null
-            }
+            if (!EXTRACTING_RESULT_OF_FROM_ITERABLE.test(methodCallExpression)) return null
+
             val iterableType = findActualType(methodCallExpression) ?: return null
             val innerType = iterableType.resolveGenerics().substitutor.substitute(iterableType.parameters[0])
             val containingClass = PsiTypesUtil.getPsiClass(innerType) ?: return null

src/main/resources/META-INF/plugin.xml

@@ -1,21 +1,20 @@
 <idea-plugin>
     <id>de.platon42.cajon</id>
     <name>Concise AssertJ Optimizing Nitpicker (Cajon)</name>
-    <vendor email="chrisly@platon42.de" url="https://github.com/chrisly42/cajon-plugin">Platon42</vendor>
+    <vendor email="chrisly@platon42.de" url="https://github.com/chrisly42/cajon-plugin">Chris 'platon42' Hodges</vendor>
 
     <description><![CDATA[
     Cajon is an IntelliJ IDEA Plugin for shortening and optimizing AssertJ assertions.
     It adds several inspections and quick fixes to fully use the fluent assertion methods
     and thus makes the intention clear and concise, also generating better messages on test failures.
-    It can also be used to convert JUnit 4 assertions to AssertJ.
+    It can also be used to convert JUnit 4 assertions and assumptions to AssertJ.
     It supports referencing inside extracting()-methods with strings, adding refactoring safety.
+    <p>
+    <a href="https://github.com/chrisly42/cajon-plugin/blob/master/README.md">Full documentation here...</a>
     ]]></description>
 
-    <!-- please see http://www.jetbrains.org/intellij/sdk/docs/basics/getting_started/build_number_ranges.html for description -->
     <idea-version since-build="173.2696.26"/>
 
-    <!-- please see http://www.jetbrains.org/intellij/sdk/docs/basics/getting_started/plugin_compatibility.html
-         on how to target different products -->
     <depends>com.intellij.modules.lang</depends>
     <depends>com.intellij.modules.platform</depends>
     <depends>com.intellij.modules.java</depends>
@@ -40,12 +39,18 @@
 
         <localInspection groupPath="Java" shortName="AssertThatBinaryExpression" enabledByDefault="true" level="WARNING"
                          implementationClass="de.platon42.intellij.plugins.cajon.inspections.AssertThatBinaryExpressionInspection"/>
+        <localInspection groupPath="Java" shortName="AssertThatObjectExpression" enabledByDefault="true" level="WARNING"
+                         implementationClass="de.platon42.intellij.plugins.cajon.inspections.AssertThatObjectExpressionInspection"/>
         <localInspection groupPath="Java" shortName="AssertThatStringExpression" enabledByDefault="true" level="WARNING"
                          implementationClass="de.platon42.intellij.plugins.cajon.inspections.AssertThatStringExpressionInspection"/>
+        <localInspection groupPath="Java" shortName="AssertThatCollectionOrMapExpression" enabledByDefault="true" level="WARNING"
+                         implementationClass="de.platon42.intellij.plugins.cajon.inspections.AssertThatCollectionOrMapExpressionInspection"/>
 
         <localInspection groupPath="Java" shortName="JoinAssertThatStatements" enabledByDefault="true" level="WARNING"
                          implementationClass="de.platon42.intellij.plugins.cajon.inspections.JoinAssertThatStatementsInspection"/>
-        <localInspection groupPath="Java" shortName="AssumeThatInsteadOfReturnInspection" enabledByDefault="true" level="WARNING"
+        <localInspection groupPath="Java" shortName="JoinVarArgsContains" enabledByDefault="true" level="WARNING"
+                         implementationClass="de.platon42.intellij.plugins.cajon.inspections.JoinVarArgsContainsInspection"/>
+        <localInspection groupPath="Java" shortName="AssumeThatInsteadOfReturn" enabledByDefault="true" level="WARNING"
                          implementationClass="de.platon42.intellij.plugins.cajon.inspections.AssumeThatInsteadOfReturnInspection"/>
 
         <localInspection groupPath="Java" shortName="AssertThatJava8Optional" enabledByDefault="true" level="WARNING"
@@ -53,6 +58,9 @@
         <localInspection groupPath="Java" shortName="AssertThatGuavaOptional" enabledByDefault="true" level="WARNING"
                          implementationClass="de.platon42.intellij.plugins.cajon.inspections.AssertThatGuavaOptionalInspection"/>
 
+        <localInspection groupPath="Java" shortName="ImplicitAssertion" enabledByDefault="true" level="WARNING"
+                         implementationClass="de.platon42.intellij.plugins.cajon.inspections.ImplicitAssertionInspection"/>
+
         <localInspection groupPath="Java" shortName="JUnitAssertToAssertJ" enabledByDefault="true" level="WARNING"
                          implementationClass="de.platon42.intellij.plugins.cajon.inspections.JUnitAssertToAssertJInspection"/>
     </extensions>

src/main/resources/inspectionDescriptions/AssertThatBinaryExpression.html

@@ -4,7 +4,6 @@ Turns a binary expression in the kind of assertThat(actual <operator> expe
 into assertThat(actual).is<operator>(expected).
 <!-- tooltip end -->
 There are over 150 combinations that are found with this inspections.
-It also detects assertThat(actual.equals(expected)) assertions.
 Also works with constant expressions on the expected side.
 Swaps actual and expected when actual is a constant expression (correctly transforming the used operator).
 </body>

src/main/resources/inspectionDescriptions/AssertThatCollectionOrMapExpression.html

@@ -0,0 +1,8 @@
+<html>
+<body>
+Turns assertThat(collectionOrMap.someMethod(arg)).isTrue/isFalse() into assertThat(collectionOrMap).someMethod(arg).
+<!-- tooltip end -->
+<br>someMethod() can be isEmpty(), contains(), and containsAll() for collections and
+isEmpty(), containsKey(), and containsValue() for maps.
+</body>
+</html>

src/main/resources/inspectionDescriptions/AssertThatObjectExpression.html

@@ -0,0 +1,9 @@
+<html>
+<body>
+Tries to simplify Object method calls such as toString, hashCode() and equals().
+<!-- tooltip end -->
+<br>Turns assertThat(object.toString()).isEqualTo(expression) into assertThat(object).hasToString(expression).
+<br>Turns assertThat(object.hashCode()).isEqualTo(otherObject.hashCode()) into assertThat(object).hasSameHashCodeAs(otherObject).
+<br>Turns assertThat(object.equals(otherObject)).isEqualTo(true) into assertThat(object).isEqualTo(otherObject) (and variations).
+</body>
+</html>

src/main/resources/inspectionDescriptions/AssertThatStringExpression.html

@@ -2,6 +2,6 @@
 <body>
 Turns assertThat(string.someMethod(arg)).isTrue/isFalse() into assertThat(string).someMethod(arg).
 <!-- tooltip end -->
-<br>someMethod() can be equals(), equalsIgnoreCase(), contentEquals(), contains(), startsWith(), and endsWith().
+<br>someMethod() can be isEmpty(), equals(), equalsIgnoreCase(), contentEquals(), contains(), startsWith(), and endsWith().
 </body>
 </html>

src/main/resources/inspectionDescriptions/ImplicitAssertion.html

@@ -0,0 +1,8 @@
+<html>
+<body>
+Finds assertion method calls that are already implicitly covered by prior assertions.
+<!-- tooltip end -->
+This works for isNotNull(), isNotEmpty() and isPresent(). It does not cover all edge cases, such as .isNotNull().isNullOrEmpty()
+or comparing against non-null literals and is conservative to not eliminate legitimate assertions.
+</body>
+</html>

src/main/resources/inspectionDescriptions/JUnitAssertToAssertJ.html

@@ -1,9 +1,10 @@
 <html>
 <body>
-Tries to convert most of the JUnit 4 assertions to AssertJ format.
+Tries to convert most of the JUnit 4 assertions and assumptions to AssertJ format.
 <!-- tooltip end -->
 <br>Works for assertTrue(), assertFalse(), assertNull(), assertNotNull(), assertEquals(), assertNotEquals(), assertSame() assertNotSame(), assertArrayEquals().
 Copes with variants with message and without, handles special versions for double and float types (including arrays).
+Also converts assumeTrue(), assumeFalse(), assumeNotNull(), assumeNoException() to assumeThat().
 <p>
     Does not support Hamcrest-Matchers. If you need that kind of conversion, you might want to check out the Assertions2AssertJ plugin by Ric Emery.
 </p>

src/main/resources/inspectionDescriptions/JoinAssertThatStatements.html

@@ -2,6 +2,9 @@
 <body>
 Joins consecutive assertThat() statements with the same actual expression together.
 <!-- tooltip end -->
-<br>Retains comments during operation. If the AssertThat()-Statement contains .extracting() methods, they will not be joined.
+<br>If the AssertThat()-Statement contains .extracting() methods, they will not be joined.
+<br>During joining multiple statements, line breaks may be added to avoid too long lines. The number of statements to join without
+adding line breaks can be configured.
+<br>Also retains comments during operation and forces a line break for these cases.
 </body>
 </html>

src/main/resources/inspectionDescriptions/JoinVarArgsContains.html

@@ -0,0 +1,11 @@
+<html>
+<body>
+Finds assertions where multiple .contains(), .containsOnlyOnce() or .doesNotContain() are
+used in a single statement that could be joined together.
+<!-- tooltip end -->
+Only works when variadic arguments are possible and will not be performed on more complex
+statements with .extracting() or .as() to avoid changing semantics.
+<br>
+Note that the quickfix does not handle comments very well and might remove them during the operation.
+</body>
+</html>

src/test/java/de/platon42/intellij/jupiter/LightCodeInsightExtension.java

@@ -8,17 +8,17 @@ import com.intellij.openapi.roots.ModifiableRootModel;
 import com.intellij.openapi.util.Disposer;
 import com.intellij.openapi.vfs.LocalFileSystem;
 import com.intellij.openapi.vfs.VirtualFile;
-import com.intellij.testFramework.LightProjectDescriptor;
-import com.intellij.testFramework.PsiTestUtil;
-import com.intellij.testFramework.UsefulTestCase;
+import com.intellij.testFramework.*;
+import com.intellij.testFramework.fixtures.IdeaTestExecutionPolicy;
 import com.intellij.testFramework.fixtures.JavaCodeInsightTestFixture;
-import com.intellij.testFramework.fixtures.LightCodeInsightFixtureTestCase;
+import com.intellij.testFramework.fixtures.LightJavaCodeInsightFixtureTestCase;
 import org.jetbrains.annotations.NotNull;
 import org.junit.jupiter.api.extension.*;
 import org.junit.jupiter.api.extension.ExtensionContext.Namespace;
 import org.junit.jupiter.api.extension.ExtensionContext.Store;
 
 import java.lang.annotation.Annotation;
+import java.lang.reflect.Method;
 import java.lang.reflect.Parameter;
 import java.net.URISyntaxException;
 import java.nio.file.Path;
@@ -26,7 +26,7 @@ import java.nio.file.Paths;
 import java.util.logging.Logger;
 import java.util.stream.Stream;
 
-public class LightCodeInsightExtension implements ParameterResolver, AfterTestExecutionCallback {
+public class LightCodeInsightExtension implements ParameterResolver, AfterTestExecutionCallback, InvocationInterceptor {
 
     private static final Logger LOG = Logger.getLogger(LightCodeInsightExtension.class.getName());
 
@@ -77,7 +77,41 @@ public class LightCodeInsightExtension implements ParameterResolver, AfterTestEx
         return context.getStore(Namespace.create(LightCodeInsightExtension.class, context.getRequiredTestMethod()));
     }
 
-    private static class LightCodeInsightFixtureTestCaseWrapper extends LightCodeInsightFixtureTestCase {
+    @Override
+    public void interceptTestMethod(Invocation<Void> invocation, ReflectiveInvocationContext<Method> invocationContext, ExtensionContext extensionContext) throws Throwable {
+        Throwable[] throwables = new Throwable[1];
+
+        Runnable runnable = () -> {
+            try {
+                TestLoggerFactory.onTestStarted();
+                invocation.proceed();
+                TestLoggerFactory.onTestFinished(true);
+            } catch (Throwable e) {
+                TestLoggerFactory.onTestFinished(false);
+                throwables[0] = e;
+            }
+        };
+
+        invokeTestRunnable(runnable);
+
+        if (throwables[0] != null) {
+            throw throwables[0];
+        }
+    }
+
+    private static void invokeTestRunnable(@NotNull Runnable runnable) {
+        IdeaTestExecutionPolicy policy = IdeaTestExecutionPolicy.current();
+        if (policy != null && !policy.runInDispatchThread()) {
+            runnable.run();
+        } else {
+            EdtTestUtilKt.runInEdtAndWait(() -> {
+                runnable.run();
+                return null;
+            });
+        }
+    }
+
+    private static class LightCodeInsightFixtureTestCaseWrapper extends LightJavaCodeInsightFixtureTestCase {
         private final ExtensionContext extensionContext;
 
         private LightCodeInsightFixtureTestCaseWrapper(ExtensionContext extensionContext) {
@@ -124,7 +158,7 @@ public class LightCodeInsightExtension implements ParameterResolver, AfterTestEx
             };
         }
 
-        protected void addJarContaining(ModifiableRootModel model, Class clazz) {
+        void addJarContaining(ModifiableRootModel model, Class clazz) {
             try {
                 Path jarPath = Paths.get(clazz.getProtectionDomain().getCodeSource().getLocation().toURI());
 

src/test/java/de/platon42/intellij/jupiter/WorkaroundUntilJupiterGetsExecutorProvider.java

@@ -1,44 +0,0 @@
-package de.platon42.intellij.jupiter;
-
-import com.intellij.testFramework.EdtTestUtilKt;
-import com.intellij.testFramework.TestLoggerFactory;
-import com.intellij.testFramework.fixtures.IdeaTestExecutionPolicy;
-import org.jetbrains.annotations.NotNull;
-
-// See https://github.com/junit-team/junit5/issues/157
-public class WorkaroundUntilJupiterGetsExecutorProvider {
-
-    protected static void runTest(Runnable test) throws Throwable {
-        Throwable[] throwables = new Throwable[1];
-
-        Runnable runnable = () -> {
-            try {
-                TestLoggerFactory.onTestStarted();
-                test.run();
-                TestLoggerFactory.onTestFinished(true);
-            } catch (Throwable e) {
-                TestLoggerFactory.onTestFinished(false);
-                e.fillInStackTrace();
-                throwables[0] = e;
-            }
-        };
-
-        invokeTestRunnable(runnable);
-
-        if (throwables[0] != null) {
-            throw throwables[0];
-        }
-    }
-
-    private static void invokeTestRunnable(@NotNull Runnable runnable) {
-        IdeaTestExecutionPolicy policy = IdeaTestExecutionPolicy.current();
-        if (policy != null && !policy.runInDispatchThread()) {
-            runnable.run();
-        } else {
-            EdtTestUtilKt.runInEdtAndWait(() -> {
-                runnable.run();
-                return null;
-            });
-        }
-    }
-}

src/test/java/de/platon42/intellij/plugins/cajon/AbstractCajonTest.kt

@@ -1,10 +1,7 @@
 package de.platon42.intellij.plugins.cajon
 
 import com.intellij.pom.java.LanguageLevel
-import com.intellij.testFramework.TestLoggerFactory
-import com.intellij.testFramework.fixtures.IdeaTestExecutionPolicy
 import com.intellij.testFramework.fixtures.JavaCodeInsightTestFixture
-import com.intellij.testFramework.runInEdtAndWait
 import de.platon42.intellij.jupiter.AddLocalJarToModule
 import de.platon42.intellij.jupiter.LightCodeInsightExtension
 import de.platon42.intellij.jupiter.TestDataPath
@@ -14,7 +11,6 @@ import org.assertj.core.api.Assertions.assertThat
 import org.junit.jupiter.api.DisplayNameGeneration
 import org.junit.jupiter.api.DisplayNameGenerator
 import org.junit.jupiter.api.extension.ExtendWith
-import java.lang.reflect.InvocationTargetException
 import java.lang.reflect.Method
 
 @ExtendWith(LightCodeInsightExtension::class)
@@ -24,48 +20,10 @@ import java.lang.reflect.Method
 @DisplayNameGeneration(AbstractCajonTest.CutOffFixtureDisplayNameGenerator::class)
 abstract class AbstractCajonTest {
 
-    // See https://github.com/junit-team/junit5/issues/157, should be resolved with junit5 5.5 M2
-    protected fun runTest(body: () -> Unit) {
-        val throwables = arrayOfNulls<Throwable>(1)
-
-        invokeTestRunnable {
-            try {
-                TestLoggerFactory.onTestStarted()
-                body()
-                TestLoggerFactory.onTestFinished(true)
-            } catch (e: InvocationTargetException) {
-                TestLoggerFactory.onTestFinished(false)
-                e.fillInStackTrace()
-                throwables[0] = e.targetException
-            } catch (e: IllegalAccessException) {
-                TestLoggerFactory.onTestFinished(false)
-                e.fillInStackTrace()
-                throwables[0] = e
-            } catch (e: Throwable) {
-                TestLoggerFactory.onTestFinished(false)
-                throwables[0] = e
-            }
-        }
-
-        if (throwables[0] != null) {
-            throw throwables[0]!!
-        }
-    }
-
-    private fun invokeTestRunnable(runnable: () -> Unit) {
-        val policy = IdeaTestExecutionPolicy.current()
-        if (policy != null && !policy.runInDispatchThread()) {
-            runnable()
-        } else {
-            runInEdtAndWait {
-                runnable()
-            }
-        }
-    }
-
     protected fun executeQuickFixes(myFixture: JavaCodeInsightTestFixture, regex: Regex, expectedFixes: Int) {
         val quickfixes = myFixture.getAllQuickFixes().filter { it.text.matches(regex) }
         assertThat(quickfixes).`as`("Fixes matched by $regex: ${myFixture.getAllQuickFixes().map { it.text }}").hasSize(expectedFixes)
+        quickfixes.forEach { it.familyName }
         quickfixes.forEach(myFixture::launchAction)
     }
 

src/test/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatBinaryExpressionInspectionTest.kt

@@ -11,12 +11,9 @@ internal class AssertThatBinaryExpressionInspectionTest : AbstractCajonTest() {
     @Test
     @TestDataSubPath("inspections/BinaryExpression")
     internal fun assertThat_of_binary_expression_can_be_moved_out(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.enableInspections(AssertThatBinaryExpressionInspection::class.java)
         myFixture.configureByFile("BinaryExpressionBefore.java")
         executeQuickFixes(myFixture, Regex.fromLiteral("Split binary expression out of assertThat()"), 149)
-            executeQuickFixes(myFixture, Regex.fromLiteral("Split equals() expression out of assertThat()"), 13)
         myFixture.checkResultByFile("BinaryExpressionAfter.java")
     }
-    }
 }

src/test/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatBooleanConditionInspectionTest.kt

@@ -11,7 +11,6 @@ internal class AssertThatBooleanConditionInspectionTest : AbstractCajonTest() {
     @Test
     @TestDataSubPath("inspections/BooleanCondition")
     internal fun assertThat_with_isEqualTo_true_or_false_can_use_isTrue_or_isFalse(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.enableInspections(AssertThatBooleanConditionInspection::class.java)
         myFixture.configureByFile("BooleanConditionBefore.java")
         executeQuickFixes(myFixture, Regex.fromLiteral("Replace isEqualTo() with isTrue()"), 6)
@@ -20,5 +19,4 @@ internal class AssertThatBooleanConditionInspectionTest : AbstractCajonTest() {
         executeQuickFixes(myFixture, Regex.fromLiteral("Replace isNotEqualTo() with isFalse()"), 4)
         myFixture.checkResultByFile("BooleanConditionAfter.java")
     }
-    }
 }

src/test/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatCollectionOrMapExpressionInspectionTest.kt

@@ -0,0 +1,27 @@
+package de.platon42.intellij.plugins.cajon.inspections
+
+import com.intellij.testFramework.fixtures.JavaCodeInsightTestFixture
+import de.platon42.intellij.jupiter.MyFixture
+import de.platon42.intellij.jupiter.TestDataSubPath
+import de.platon42.intellij.plugins.cajon.AbstractCajonTest
+import org.junit.jupiter.api.Test
+
+internal class AssertThatCollectionOrMapExpressionInspectionTest : AbstractCajonTest() {
+
+    @Test
+    @TestDataSubPath("inspections/CollectionMapExpression")
+    internal fun assertThat_with_certain_Collection_and_Map_methods(@MyFixture myFixture: JavaCodeInsightTestFixture) {
+        myFixture.enableInspections(AssertThatCollectionOrMapExpressionInspection::class.java)
+        myFixture.configureByFile("CollectionMapExpressionBefore.java")
+        executeQuickFixes(myFixture, Regex.fromLiteral("Remove isEmpty() of actual expression and use assertThat().isEmpty() instead"), 4)
+        executeQuickFixes(myFixture, Regex.fromLiteral("Remove contains() of actual expression and use assertThat().contains() instead"), 2)
+        executeQuickFixes(myFixture, Regex.fromLiteral("Remove containsAll() of actual expression and use assertThat().containsAll() instead"), 2)
+        executeQuickFixes(myFixture, Regex.fromLiteral("Remove containsKey() of actual expression and use assertThat().containsKey() instead"), 2)
+        executeQuickFixes(myFixture, Regex.fromLiteral("Remove containsValue() of actual expression and use assertThat().containsValue() instead"), 2)
+        executeQuickFixes(myFixture, Regex.fromLiteral("Remove isEmpty() of actual expression and use assertThat().isNotEmpty() instead"), 5)
+        executeQuickFixes(myFixture, Regex.fromLiteral("Remove contains() of actual expression and use assertThat().doesNotContain() instead"), 2)
+        executeQuickFixes(myFixture, Regex.fromLiteral("Remove containsKey() of actual expression and use assertThat().doesNotContainKey() instead"), 2)
+        executeQuickFixes(myFixture, Regex.fromLiteral("Remove containsValue() of actual expression and use assertThat().doesNotContainValue() instead"), 2)
+        myFixture.checkResultByFile("CollectionMapExpressionAfter.java")
+    }
+}

src/test/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatEnumerableIsEmptyInspectionTest.kt

@@ -11,11 +11,9 @@ internal class AssertThatEnumerableIsEmptyInspectionTest : AbstractCajonTest() {
     @Test
     @TestDataSubPath("inspections/EnumerableIsEmpty")
     internal fun assertThat_with_hasSize_zero_can_use_isEmpty(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.enableInspections(AssertThatEnumerableIsEmptyInspection::class.java)
         myFixture.configureByFile("EnumerableIsEmptyBefore.java")
         executeQuickFixes(myFixture, Regex.fromLiteral("Replace hasSize() with isEmpty()"), 5)
         myFixture.checkResultByFile("EnumerableIsEmptyAfter.java")
     }
-    }
 }

src/test/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatGuavaOptionalInspectionTest.kt

@@ -14,33 +14,30 @@ internal class AssertThatGuavaOptionalInspectionTest : AbstractCajonTest() {
 
     @Test
     internal fun assertThat_get_or_isPresent_for_Guava_Optional_can_be_simplified(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.enableInspections(AssertThatGuavaOptionalInspection::class.java)
         myFixture.configureByFile("GuavaOptionalBefore.java")
         executeQuickFixes(myFixture, Regex.fromLiteral("Remove isPresent() of actual expression and use assertThat().isPresent() instead"), 6)
         executeQuickFixes(myFixture, Regex.fromLiteral("Remove isPresent() of actual expression and use assertThat().isAbsent() instead"), 5)
+        executeQuickFixes(myFixture, Regex.fromLiteral("Remove orNull() of actual expression and use assertThat().isPresent() instead"), 2)
+        executeQuickFixes(myFixture, Regex.fromLiteral("Remove orNull() of actual expression and use assertThat().isAbsent() instead"), 2)
         executeQuickFixes(myFixture, Regex.fromLiteral("Remove get() of actual expression and use assertThat().contains() instead"), 1)
         executeQuickFixes(myFixture, Regex.fromLiteral("Unwrap expected expression and replace isEqualTo() with contains()"), 6)
         executeQuickFixes(myFixture, Regex.fromLiteral("Replace isEqualTo() with Guava assertThat().isAbsent()"), 3)
         executeQuickFixes(myFixture, Regex.fromLiteral("Replace isNotEqualTo() with Guava assertThat().isPresent()"), 3)
         myFixture.checkResultByFile("GuavaOptionalAfter.java")
     }
-    }
 
     @Test
     internal fun adds_missing_Guava_import_any_order(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.enableInspections(AssertThatGuavaOptionalInspection::class.java)
         myFixture.configureByFile("WithoutPriorGuavaImportBefore.java")
         executeQuickFixes(myFixture, Regex(".*eplace .* with .*"), 4)
         executeQuickFixes(myFixture, Regex("Remove .*"), 3)
         myFixture.checkResultByFile("WithoutPriorGuavaImportAfter.java")
     }
-    }
 
     @Test
     internal fun adds_missing_Guava_import_isAbsent_first(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.enableInspections(AssertThatGuavaOptionalInspection::class.java)
         myFixture.configureByFile("WithoutPriorGuavaImportBefore.java")
         executeQuickFixes(myFixture, Regex.fromLiteral("Replace isEqualTo() with Guava assertThat().isAbsent()"), 1)
@@ -48,5 +45,4 @@ internal class AssertThatGuavaOptionalInspectionTest : AbstractCajonTest() {
         executeQuickFixes(myFixture, Regex("Remove .*"), 3)
         myFixture.checkResultByFile("WithoutPriorGuavaImportAfter.java")
     }
-    }
 }

src/test/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatInstanceOfInspectionTest.kt

@@ -11,12 +11,10 @@ internal class AssertThatInstanceOfInspectionTest : AbstractCajonTest() {
     @Test
     @TestDataSubPath("inspections/InstanceOf")
     internal fun assertThat_with_instanceof_can_be_moved_out(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.enableInspections(AssertThatInstanceOfInspection::class.java)
         myFixture.configureByFile("InstanceOfBefore.java")
         executeQuickFixes(myFixture, Regex.fromLiteral("Remove instanceof in actual expression and use assertThat().isInstanceOf() instead"), 6)
         executeQuickFixes(myFixture, Regex.fromLiteral("Remove instanceof in actual expression and use assertThat().isNotInstanceOf() instead"), 6)
         myFixture.checkResultByFile("InstanceOfAfter.java")
     }
-    }
 }

src/test/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatInvertedBooleanConditionInspectionTest.kt

@@ -11,11 +11,9 @@ internal class AssertThatInvertedBooleanConditionInspectionTest : AbstractCajonT
     @Test
     @TestDataSubPath("inspections/InvertedBooleanCondition")
     internal fun assertThat_with_inverted_boolean_condition_can_be_inverted(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.enableInspections(AssertThatInvertedBooleanConditionInspection::class.java)
         myFixture.configureByFile("InvertedBooleanConditionBefore.java")
         executeQuickFixes(myFixture, Regex.fromLiteral("Invert condition in assertThat()"), 25)
         myFixture.checkResultByFile("InvertedBooleanConditionAfter.java")
     }
-    }
 }

src/test/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatJava8OptionalInspectionTest.kt

@@ -11,11 +11,12 @@ internal class AssertThatJava8OptionalInspectionTest : AbstractCajonTest() {
     @Test
     @TestDataSubPath("inspections/Java8Optional")
     internal fun assertThat_get_or_isPresent_for_Java8_Optional_can_be_simplified(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.enableInspections(AssertThatJava8OptionalInspection::class.java)
         myFixture.configureByFile("Java8OptionalBefore.java")
         executeQuickFixes(myFixture, Regex.fromLiteral("Remove isPresent() of actual expression and use assertThat().isPresent() instead"), 6)
         executeQuickFixes(myFixture, Regex.fromLiteral("Remove isPresent() of actual expression and use assertThat().isNotPresent() instead"), 5)
+        executeQuickFixes(myFixture, Regex.fromLiteral("Remove orElse() of actual expression and use assertThat().isPresent() instead"), 2)
+        executeQuickFixes(myFixture, Regex.fromLiteral("Remove orElse() of actual expression and use assertThat().isNotPresent() instead"), 2)
         executeQuickFixes(myFixture, Regex.fromLiteral("Remove get() of actual expression and use assertThat().contains() instead"), 1)
         executeQuickFixes(myFixture, Regex.fromLiteral("Remove get() of actual expression and use assertThat().containsSame() instead"), 1)
         executeQuickFixes(myFixture, Regex.fromLiteral("Replace isEqualTo() with isNotPresent()"), 1)
@@ -23,5 +24,4 @@ internal class AssertThatJava8OptionalInspectionTest : AbstractCajonTest() {
         executeQuickFixes(myFixture, Regex.fromLiteral("Unwrap expected expression and replace isEqualTo() with contains()"), 2)
         myFixture.checkResultByFile("Java8OptionalAfter.java")
     }
-    }
 }

src/test/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatObjectExpressionInspectionTest.kt

@@ -0,0 +1,22 @@
+package de.platon42.intellij.plugins.cajon.inspections
+
+import com.intellij.testFramework.fixtures.JavaCodeInsightTestFixture
+import de.platon42.intellij.jupiter.MyFixture
+import de.platon42.intellij.jupiter.TestDataSubPath
+import de.platon42.intellij.plugins.cajon.AbstractCajonTest
+import org.junit.jupiter.api.Test
+
+internal class AssertThatObjectExpressionInspectionTest : AbstractCajonTest() {
+
+    @Test
+    @TestDataSubPath("inspections/ObjectExpression")
+    internal fun assertThat_with_certain_Object_methods(@MyFixture myFixture: JavaCodeInsightTestFixture) {
+        myFixture.enableInspections(AssertThatObjectExpressionInspection::class.java)
+        myFixture.configureByFile("ObjectExpressionBefore.java")
+        executeQuickFixes(myFixture, Regex.fromLiteral("Remove equals() of actual expression and use assertThat().isEqualTo() instead"), 4)
+        executeQuickFixes(myFixture, Regex.fromLiteral("Remove equals() of actual expression and use assertThat().isNotEqualTo() instead"), 3)
+        executeQuickFixes(myFixture, Regex.fromLiteral("Replace calls to hashCode() with hasSameHashCodeAs()"), 1)
+        executeQuickFixes(myFixture, Regex.fromLiteral("Remove toString() of actual expression and use assertThat().hasToString() instead"), 1)
+        myFixture.checkResultByFile("ObjectExpressionAfter.java")
+    }
+}

src/test/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatObjectIsNullOrNotNullInspectionTest.kt

@@ -11,12 +11,10 @@ internal class AssertThatObjectIsNullOrNotNullInspectionTest : AbstractCajonTest
     @Test
     @TestDataSubPath("inspections/ObjectIsNullOrNotNull")
     internal fun assertThat_with_isEqualTo_null_can_use_isNull(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.enableInspections(AssertThatObjectIsNullOrNotNullInspection::class.java)
         myFixture.configureByFile("ObjectIsNullOrNotNullBefore.java")
         executeQuickFixes(myFixture, Regex.fromLiteral("Replace isEqualTo() with isNull()"), 4)
         executeQuickFixes(myFixture, Regex.fromLiteral("Replace isNotEqualTo() with isNotNull()"), 5)
         myFixture.checkResultByFile("ObjectIsNullOrNotNullAfter.java")
     }
-    }
 }

src/test/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatSizeInspectionTest.kt

@@ -13,7 +13,6 @@ internal class AssertThatSizeInspectionTest : AbstractCajonTest() {
     @Test
     @TestDataSubPath("inspections/Size")
     internal fun assertThat_size_of_array_or_collection_can_be_simplified(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.enableInspections(AssertThatSizeInspection::class.java)
         myFixture.configureByFile("SizeBefore.java")
         assertThat(myFixture.doHighlighting()).extrakting { it.description }.containsOnlyOnce("Try to operate on the iterable itself rather than its size")
@@ -34,5 +33,4 @@ internal class AssertThatSizeInspectionTest : AbstractCajonTest() {
         executeQuickFixes(myFixture, Regex.fromLiteral("Remove size determination of expected expression and replace hasSize() with hasSameSizeAs()"), 14)
         myFixture.checkResultByFile("SizeAfter.java")
     }
-    }
 }

src/test/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatStringExpressionInspectionTest.kt

@@ -11,17 +11,16 @@ internal class AssertThatStringExpressionInspectionTest : AbstractCajonTest() {
     @Test
     @TestDataSubPath("inspections/StringExpression")
     internal fun assertThat_with_certain_String_methods(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.enableInspections(AssertThatStringExpressionInspection::class.java)
         myFixture.configureByFile("StringExpressionBefore.java")
-            executeQuickFixes(myFixture, Regex.fromLiteral("Remove isEmpty() of actual expression and use assertThat().isEmpty() instead"), 2)
+        executeQuickFixes(myFixture, Regex.fromLiteral("Remove isEmpty() of actual expression and use assertThat().isEmpty() instead"), 3)
         executeQuickFixes(myFixture, Regex.fromLiteral("Remove equals() of actual expression and use assertThat().isEqualTo() instead"), 2)
         executeQuickFixes(myFixture, Regex.fromLiteral("Remove equalsIgnoreCase() of actual expression and use assertThat().isEqualToIgnoringCase() instead"), 2)
         executeQuickFixes(myFixture, Regex.fromLiteral("Remove contentEquals() of actual expression and use assertThat().isEqualTo() instead"), 4)
         executeQuickFixes(myFixture, Regex.fromLiteral("Remove contains() of actual expression and use assertThat().contains() instead"), 4)
         executeQuickFixes(myFixture, Regex.fromLiteral("Remove startsWith() of actual expression and use assertThat().startsWith() instead"), 2)
         executeQuickFixes(myFixture, Regex.fromLiteral("Remove endsWith() of actual expression and use assertThat().endsWith() instead"), 2)
-            executeQuickFixes(myFixture, Regex.fromLiteral("Remove isEmpty() of actual expression and use assertThat().isNotEmpty() instead"), 2)
+        executeQuickFixes(myFixture, Regex.fromLiteral("Remove isEmpty() of actual expression and use assertThat().isNotEmpty() instead"), 3)
         executeQuickFixes(myFixture, Regex.fromLiteral("Remove equals() of actual expression and use assertThat().isNotEqualTo() instead"), 2)
         executeQuickFixes(myFixture, Regex.fromLiteral("Remove equalsIgnoreCase() of actual expression and use assertThat().isNotEqualToIgnoringCase() instead"), 2)
         executeQuickFixes(myFixture, Regex.fromLiteral("Remove contentEquals() of actual expression and use assertThat().isNotEqualTo() instead"), 4)
@@ -30,5 +29,4 @@ internal class AssertThatStringExpressionInspectionTest : AbstractCajonTest() {
         executeQuickFixes(myFixture, Regex.fromLiteral("Remove endsWith() of actual expression and use assertThat().doesNotEndWith() instead"), 3)
         myFixture.checkResultByFile("StringExpressionAfter.java")
     }
-    }
 }

src/test/java/de/platon42/intellij/plugins/cajon/inspections/AssertThatStringIsEmptyInspectionTest.kt

@@ -13,7 +13,6 @@ internal class AssertThatStringIsEmptyInspectionTest : AbstractCajonTest() {
     @Test
     @TestDataSubPath("inspections/StringIsEmpty")
     internal fun assertThat_with_isEqualTo_emptyString_can_use_isEmpty(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.enableInspections(AssertThatStringIsEmptyInspection::class.java)
         myFixture.configureByFile("StringIsEmptyBefore.java")
         val highlights = myFixture.doHighlighting()
@@ -25,5 +24,4 @@ internal class AssertThatStringIsEmptyInspectionTest : AbstractCajonTest() {
         executeQuickFixes(myFixture, Regex.fromLiteral("Replace hasSize() with isEmpty()"), 3)
         myFixture.checkResultByFile("StringIsEmptyAfter.java")
     }
-    }
 }

src/test/java/de/platon42/intellij/plugins/cajon/inspections/AssumeThatInsteadOfReturnInspectionTest.kt

@@ -14,11 +14,9 @@ internal class AssumeThatInsteadOfReturnInspectionTest : AbstractCajonTest() {
     @Test
     @TestDataSubPath("inspections/AssumeThat")
     internal fun conditional_returns_can_be_replaced_by_assumeThat(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.enableInspections(AssumeThatInsteadOfReturnInspection::class.java)
         myFixture.configureByFile("AssumeThatBefore.java")
-            executeQuickFixes(myFixture, Regex.fromLiteral("Replace if statement by assumeTrue()"), 4)
+        executeQuickFixes(myFixture, Regex.fromLiteral("Replace if statement by assumeTrue()"), 5)
         myFixture.checkResultByFile("AssumeThatAfter.java")
     }
-    }
 }

src/test/java/de/platon42/intellij/plugins/cajon/inspections/ImplicitAssertionInspectionTest.kt

@@ -0,0 +1,24 @@
+package de.platon42.intellij.plugins.cajon.inspections
+
+import com.intellij.testFramework.fixtures.JavaCodeInsightTestFixture
+import de.platon42.intellij.jupiter.AddLocalJarToModule
+import de.platon42.intellij.jupiter.MyFixture
+import de.platon42.intellij.jupiter.TestDataSubPath
+import de.platon42.intellij.plugins.cajon.AbstractCajonTest
+import org.assertj.core.api.Assertions
+import org.junit.jupiter.api.Test
+
+@AddLocalJarToModule(com.google.common.base.Optional::class, org.assertj.guava.api.Assertions::class, Assertions::class)
+internal class ImplicitAssertionInspectionTest : AbstractCajonTest() {
+
+    @Test
+    @TestDataSubPath("inspections/ImplicitAssertion")
+    internal fun implicit_assertions_can_be_removed(@MyFixture myFixture: JavaCodeInsightTestFixture) {
+        myFixture.enableInspections(ImplicitAssertionInspection::class.java)
+        myFixture.configureByFile("ImplicitAssertionBefore.java")
+        executeQuickFixes(myFixture, Regex("Delete implicit isNotNull\\(\\) covered by .*"), 101)
+        executeQuickFixes(myFixture, Regex("Delete implicit isNotEmpty\\(\\) covered by .*"), 17)
+        executeQuickFixes(myFixture, Regex("Delete implicit isPresent\\(\\) covered by .*"), 8)
+        myFixture.checkResultByFile("ImplicitAssertionAfter.java")
+    }
+}

src/test/java/de/platon42/intellij/plugins/cajon/inspections/JUnitAssertToAssertJInspectionTest.kt

@@ -15,11 +15,10 @@ internal class JUnitAssertToAssertJInspectionTest : AbstractCajonTest() {
     @Test
     @TestDataSubPath("inspections/JUnitAssertToAssertJ")
     internal fun junit_Assertions_can_be_converted_into_AssertJ(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.enableInspections(JUnitAssertToAssertJInspection::class.java)
         myFixture.configureByFile("JUnitAssertToAssertJInspectionBefore.java")
-            executeQuickFixes(myFixture, Regex("Convert assert.*\\(\\) to assertThat\\(\\).*"), 38)
+        executeQuickFixes(myFixture, Regex("Convert assert.*\\(\\) to assertThat\\(\\).*"), 48)
+        executeQuickFixes(myFixture, Regex("Convert assume.*\\(\\) to assumeThat\\(\\).*"), 7)
         myFixture.checkResultByFile("JUnitAssertToAssertJInspectionAfter.java")
     }
-    }
 }

src/test/java/de/platon42/intellij/plugins/cajon/inspections/JoinAssertThatStatementsInspectionTest.kt

@@ -11,11 +11,9 @@ internal class JoinAssertThatStatementsInspectionTest : AbstractCajonTest() {
     @Test
     @TestDataSubPath("inspections/JoinStatements")
     internal fun assertThat_statements_can_be_joined_together(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.enableInspections(JoinAssertThatStatementsInspection::class.java)
         myFixture.configureByFile("JoinStatementsBefore.java")
         executeQuickFixes(myFixture, Regex.fromLiteral("Join assertThat() statements"), 5)
         myFixture.checkResultByFile("JoinStatementsAfter.java")
     }
-    }
 }

src/test/java/de/platon42/intellij/plugins/cajon/inspections/JoinVarArgsContainsInspectionTest.kt

@@ -0,0 +1,19 @@
+package de.platon42.intellij.plugins.cajon.inspections
+
+import com.intellij.testFramework.fixtures.JavaCodeInsightTestFixture
+import de.platon42.intellij.jupiter.MyFixture
+import de.platon42.intellij.jupiter.TestDataSubPath
+import de.platon42.intellij.plugins.cajon.AbstractCajonTest
+import org.junit.jupiter.api.Test
+
+internal class JoinVarArgsContainsInspectionTest : AbstractCajonTest() {
+
+    @Test
+    @TestDataSubPath("inspections/JoinVarArgsContains")
+    internal fun join_contains_and_doesNotContain_together_where_possible(@MyFixture myFixture: JavaCodeInsightTestFixture) {
+        myFixture.enableInspections(JoinVarArgsContainsInspection::class.java)
+        myFixture.configureByFile("JoinVarArgsContainsBefore.java")
+        executeQuickFixes(myFixture, Regex.fromLiteral("Join multiple arguments to variadic argument method calls"), 3)
+        myFixture.checkResultByFile("JoinVarArgsContainsAfter.java")
+    }
+}

src/test/java/de/platon42/intellij/plugins/cajon/references/ExtractorReferenceContributorTest.kt

@@ -5,6 +5,7 @@ import de.platon42.intellij.jupiter.MyFixture
 import de.platon42.intellij.jupiter.TestDataSubPath
 import de.platon42.intellij.plugins.cajon.AbstractCajonTest
 import org.assertj.core.api.Assertions.assertThat
+import org.assertj.core.api.Assertions.assertThatThrownBy
 import org.junit.jupiter.api.Test
 
 
@@ -13,81 +14,67 @@ internal class ExtractorReferenceContributorTest : AbstractCajonTest() {
 
     @Test
     internal fun extractor_is_able_to_find_reference_for_field_extracting(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.configureByFiles("FindReference1.java", "Address.java", "Contact.java")
         assertThat(myFixture.elementAtCaret.text).isEqualTo("private String name;")
     }
-    }
 
     @Test
     internal fun extractor_is_able_to_find_reference_for_first_part_of_a_path(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.configureByFiles("FindReference2.java", "Address.java", "Contact.java")
         assertThat(myFixture.elementAtCaret.text).isEqualTo("protected Address address;")
     }
-    }
 
     @Test
     internal fun extractor_is_able_to_find_reference_for_second_part_of_a_path_and_both_getter_and_field(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.configureByFiles("FindReference3.java", "Address.java", "Contact.java")
         assertThat(myFixture.elementAtCaret.text).startsWith("private String street;")
     }
-    }
 
     @Test
     internal fun extractor_is_able_to_find_reference_on_a_bare_method_call(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.configureByFiles("FindReference4.java", "Address.java", "Contact.java")
         assertThat(myFixture.elementAtCaret.text).startsWith("public Boolean getREALLYnoMAILINGS()")
     }
-    }
 
     @Test
     internal fun extractor_is_able_to_find_reference_with_only_Getter_on_second_part(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.configureByFiles("FindReference5.java", "Address.java", "Contact.java")
         assertThat(myFixture.elementAtCaret.text).startsWith("public boolean isNoMailings()")
     }
-    }
 
     @Test
     internal fun extractor_is_able_to_find_reference_using_byName_extractor(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.configureByFiles("FindReference6.java", "Address.java", "Contact.java")
         assertThat(myFixture.elementAtCaret.text).isEqualTo("private String name;")
     }
-    }
 
     @Test
     internal fun extractor_is_able_to_find_reference_using_resultOf_extractor(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.configureByFiles("FindReference7.java", "Address.java", "Contact.java")
         assertThat(myFixture.elementAtCaret.text).startsWith("public String getStreetName()")
     }
-    }
 
     @Test
     internal fun extractor_is_able_to_find_reference_for_field_extraction_on_list(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.configureByFiles("FindReference8.java", "Address.java", "Contact.java")
         assertThat(myFixture.elementAtCaret.text).isEqualTo("private String name;")
     }
-    }
 
     @Test
     internal fun extractor_is_able_to_find_reference_for_field_flat_extraction_of_path_on_list(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.configureByFiles("FindReference9.java", "Address.java", "Contact.java")
         assertThat(myFixture.elementAtCaret.text).startsWith("private String street;")
     }
-    }
 
     @Test
     internal fun extractor_is_able_to_find_reference_for_extraction_on_result_of_method(@MyFixture myFixture: JavaCodeInsightTestFixture) {
-        runTest {
         myFixture.configureByFiles("FindReference10.java", "Address.java", "Contact.java")
         assertThat(myFixture.elementAtCaret.text).startsWith("public String getStreetName()")
     }
+
+    @Test
+    internal fun extractor_is_unable_to_find_reference(@MyFixture myFixture: JavaCodeInsightTestFixture) {
+        myFixture.configureByFiles("FindReference11.java", "Address.java", "Contact.java")
+        assertThatThrownBy { myFixture.elementAtCaret.text }.isInstanceOf(AssertionError::class.java)
     }
 }

src/test/resources/inspections/AssumeThat/AssumeThatAfter.java

@@ -38,6 +38,13 @@ public class AssumeThat {
         assertThat(foobar).isNotEmpty();
     }
 
+    @org.junit.jupiter.api.Test
+    public void junit5_return_with_empty_else_block() {
+        String foobar = System.getProperty("car_manufacturer");
+        assumeThat(foobar.equals("Volkswagen")).isFalse();
+        assertThat(foobar).isNotEmpty();
+    }
+
     @org.junit.jupiter.api.TestTemplate
     public void junit5_return_inside_recursion_with_comments() {
         String foobar = System.getProperty("car_manufacturer");

src/test/resources/inspections/AssumeThat/AssumeThatBefore.java

@@ -39,6 +39,13 @@ public class AssumeThat {
         assertThat(foobar).isNotEmpty();
     }
 
+    @org.junit.jupiter.api.Test
+    public void junit5_return_with_empty_else_block() {
+        String foobar = System.getProperty("car_manufacturer");
+        if (foobar.equals("Volkswagen")) return; else {}
+        assertThat(foobar).isNotEmpty();
+    }
+
     @org.junit.jupiter.api.TestTemplate
     public void junit5_return_inside_recursion_with_comments() {
         String foobar = System.getProperty("car_manufacturer");

src/test/resources/inspections/BinaryExpression/BinaryExpressionAfter.java

@@ -1,4 +1,5 @@
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
 
 public class BinaryExpression {
 
@@ -146,12 +147,12 @@ public class BinaryExpression {
         assertThat(numberObjAct).isGreaterThan(1);
         assertThat(numberObjAct).isGreaterThan(1);
 
-        assertThat(numberObjAct).as("doh!").isEqualTo(numberObjExp);
-        assertThat(numberObjAct).isEqualTo(numberObjExp);
-        assertThat(numberObjAct).isEqualTo(numberObjExp);
-        assertThat(numberObjAct).isNotEqualTo(numberObjExp);
-        assertThat(numberObjAct).isNotEqualTo(numberObjExp);
-        assertThat(numberObjAct).isNotEqualTo(numberObjExp);
+        assertThat(numberObjAct.equals(numberObjExp)).as("doh!").isTrue();
+        assertThat(numberObjAct.equals(numberObjExp)).isEqualTo(true);
+        assertThat(numberObjAct.equals(numberObjExp)).isNotEqualTo(false);
+        assertThat(numberObjAct.equals(numberObjExp)).isFalse();
+        assertThat(numberObjAct.equals(numberObjExp)).isEqualTo(false);
+        assertThat(numberObjAct.equals(numberObjExp)).isNotEqualTo(true);
 
         assertThat(stringAct).as("doh!").isSameAs(stringExp);
         assertThat(stringAct).isSameAs(stringExp);
@@ -160,12 +161,12 @@ public class BinaryExpression {
         assertThat(stringAct).isNotSameAs(stringExp);
         assertThat(stringAct).isNotSameAs(stringExp);
 
-        assertThat(stringAct).as("doh!").isEqualTo(stringExp);
-        assertThat(stringAct).isEqualTo(stringExp);
-        assertThat(stringAct).isEqualTo(stringExp);
-        assertThat(stringAct).isNotEqualTo(stringExp);
-        assertThat(stringAct).isNotEqualTo(stringExp);
-        assertThat(stringAct).isNotEqualTo(stringExp);
+        assertThat(stringAct.equals(stringExp)).as("doh!").isTrue();
+        assertThat(stringAct.equals(stringExp)).isEqualTo(true);
+        assertThat(stringAct.equals(stringExp)).isNotEqualTo(false);
+        assertThat(stringAct.equals(stringExp)).isFalse();
+        assertThat(stringAct.equals(stringExp)).isEqualTo(false);
+        assertThat(stringAct.equals(stringExp)).isNotEqualTo(true);
 
         assertThat(stringAct).as("doh!").isNotSameAs(stringExp);
         assertThat(stringAct).isNotSameAs(stringExp);
@@ -194,6 +195,9 @@ public class BinaryExpression {
         assertThat(primAct).as("doh!").isEqualTo(primExp).isEqualTo(primExp);
         assertThat(primAct == primExp).isFalse().as("doh!").isEqualTo(true);
 
-        assertThat(numberObjAct).as("doh!").isEqualTo(numberObjExp).isEqualTo(numberObjExp);
+        assertThat(numberObjAct.equals(numberObjExp)).as("doh!").isTrue().isEqualTo(true);
+
+        org.junit.Assert.assertThat(stringAct, null);
+        fail("oh no!");
     }
 }

src/test/resources/inspections/BinaryExpression/BinaryExpressionBefore.java

@@ -1,4 +1,5 @@
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
 
 public class BinaryExpression {
 
@@ -195,5 +196,8 @@ public class BinaryExpression {
         assertThat(primAct == primExp).isFalse().as("doh!").isEqualTo(true);
 
         assertThat(numberObjAct.equals(numberObjExp)).as("doh!").isTrue().isEqualTo(true);
+
+        org.junit.Assert.assertThat(stringAct, null);
+        fail("oh no!");
     }
 }

src/test/resources/inspections/BooleanCondition/BooleanConditionAfter.java

@@ -1,4 +1,5 @@
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
 
 public class BooleanCondition {
 
@@ -30,5 +31,9 @@ public class BooleanCondition {
         assertThat("").isEqualTo(Boolean.TRUE);
 
         assertThat(primitive).isTrue().as("foo").isTrue().as("bar").isTrue().isFalse();
+
+        assertThat(object).isEqualTo(Boolean.TYPE);
+        org.junit.Assert.assertThat(object, null);
+        fail("oh no!");
     }
 }

src/test/resources/inspections/BooleanCondition/BooleanConditionBefore.java

@@ -1,4 +1,5 @@
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
 
 public class BooleanCondition {
 
@@ -30,5 +31,9 @@ public class BooleanCondition {
         assertThat("").isEqualTo(Boolean.TRUE);
 
         assertThat(primitive).isEqualTo(Boolean.TRUE).as("foo").isEqualTo(true).as("bar").isTrue().isFalse();
+
+        assertThat(object).isEqualTo(Boolean.TYPE);
+        org.junit.Assert.assertThat(object, null);
+        fail("oh no!");
     }
 }

src/test/resources/inspections/CollectionMapExpression/CollectionMapExpressionAfter.java

@@ -0,0 +1,48 @@
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
+
+import java.util.*;
+
+public class CollectionMapExpression {
+
+    private void collectionMapExpression() {
+        List<String> stringList = new ArrayList<>();
+        List<String> anotherList = new ArrayList<>();
+        Map<String, Integer> keyValueMap = new HashMap<>();
+
+        assertThat(stringList).as("foo").isEmpty();
+        assertThat(stringList).isEmpty();
+        assertThat(stringList).contains("foo");
+        assertThat(stringList).contains("foo");
+        assertThat(stringList).containsAll(anotherList);
+        assertThat(stringList).containsAll(anotherList);
+
+        assertThat(stringList).as("foo").isNotEmpty();
+        assertThat(stringList).isNotEmpty();
+        assertThat(stringList).doesNotContain("foo");
+        assertThat(stringList).doesNotContain("foo");
+        assertThat(stringList.containsAll(anotherList)).isEqualTo(false);
+        assertThat(stringList.containsAll(anotherList)).isFalse();
+
+        assertThat(keyValueMap).as("foo").isEmpty();
+        assertThat(keyValueMap).isEmpty();
+        assertThat(keyValueMap).containsKey("foo");
+        assertThat(keyValueMap).containsKey("foo");
+        assertThat(keyValueMap).containsValue(2);
+        assertThat(keyValueMap).containsValue(2);
+
+        assertThat(keyValueMap).as("foo").isNotEmpty();
+        assertThat(keyValueMap).isNotEmpty();
+        assertThat(keyValueMap).doesNotContainKey("foo");
+        assertThat(keyValueMap).doesNotContainKey("foo");
+        assertThat(keyValueMap).doesNotContainValue(2);
+        assertThat(keyValueMap).doesNotContainValue(2);
+
+        assertThat(stringList).as("foo").isNotEmpty().as("bar").isNotEmpty();
+        assertThat(stringList.isEmpty()).as("foo").isEqualTo(false).as("bar").isTrue();
+        assertThat(stringList.isEmpty()).as("foo").satisfies(it -> it.booleanValue()).as("bar").isFalse();
+
+        org.junit.Assert.assertThat(stringList, null);
+        fail("oh no!");
+    }
+}

src/test/resources/inspections/CollectionMapExpression/CollectionMapExpressionBefore.java

@@ -0,0 +1,48 @@
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
+
+import java.util.*;
+
+public class CollectionMapExpression {
+
+    private void collectionMapExpression() {
+        List<String> stringList = new ArrayList<>();
+        List<String> anotherList = new ArrayList<>();
+        Map<String, Integer> keyValueMap = new HashMap<>();
+
+        assertThat(stringList.isEmpty()).as("foo").isEqualTo(true);
+        assertThat(stringList.isEmpty()).isTrue();
+        assertThat(stringList.contains("foo")).isEqualTo(true);
+        assertThat(stringList.contains("foo")).isTrue();
+        assertThat(stringList.containsAll(anotherList)).isEqualTo(true);
+        assertThat(stringList.containsAll(anotherList)).isTrue();
+
+        assertThat(stringList.isEmpty()).as("foo").isEqualTo(false);
+        assertThat(stringList.isEmpty()).isFalse();
+        assertThat(stringList.contains("foo")).isEqualTo(false);
+        assertThat(stringList.contains("foo")).isFalse();
+        assertThat(stringList.containsAll(anotherList)).isEqualTo(false);
+        assertThat(stringList.containsAll(anotherList)).isFalse();
+
+        assertThat(keyValueMap.isEmpty()).as("foo").isEqualTo(true);
+        assertThat(keyValueMap.isEmpty()).isTrue();
+        assertThat(keyValueMap.containsKey("foo")).isEqualTo(true);
+        assertThat(keyValueMap.containsKey("foo")).isTrue();
+        assertThat(keyValueMap.containsValue(2)).isEqualTo(true);
+        assertThat(keyValueMap.containsValue(2)).isTrue();
+
+        assertThat(keyValueMap.isEmpty()).as("foo").isEqualTo(false);
+        assertThat(keyValueMap.isEmpty()).isFalse();
+        assertThat(keyValueMap.containsKey("foo")).isEqualTo(false);
+        assertThat(keyValueMap.containsKey("foo")).isFalse();
+        assertThat(keyValueMap.containsValue(2)).isEqualTo(false);
+        assertThat(keyValueMap.containsValue(2)).isFalse();
+
+        assertThat(stringList.isEmpty()).as("foo").isEqualTo(false).as("bar").isFalse();
+        assertThat(stringList.isEmpty()).as("foo").isEqualTo(false).as("bar").isTrue();
+        assertThat(stringList.isEmpty()).as("foo").satisfies(it -> it.booleanValue()).as("bar").isFalse();
+
+        org.junit.Assert.assertThat(stringList, null);
+        fail("oh no!");
+    }
+}

src/test/resources/inspections/EnumerableIsEmpty/EnumerableIsEmptyAfter.java

@@ -1,6 +1,7 @@
 import java.util.ArrayList;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
 
 public class EnumerableIsEmpty {
 
@@ -16,5 +17,8 @@ public class EnumerableIsEmpty {
         assertThat(new Long[1]).as("etc").hasSize(1);
 
         assertThat("string").as("foo").hasSize(0).hasSameSizeAs("foo").isEmpty();
+
+        org.junit.Assert.assertThat("foo", null);
+        fail("oh no!");
     }
 }

src/test/resources/inspections/EnumerableIsEmpty/EnumerableIsEmptyBefore.java

@@ -1,6 +1,7 @@
 import java.util.ArrayList;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
 
 public class EnumerableIsEmpty {
 
@@ -16,5 +17,8 @@ public class EnumerableIsEmpty {
         assertThat(new Long[1]).as("etc").hasSize(1);
 
         assertThat("string").as("foo").hasSize(0).hasSameSizeAs("foo").hasSize(0);
+
+        org.junit.Assert.assertThat("foo", null);
+        fail("oh no!");
     }
 }

src/test/resources/inspections/GuavaOptional/GuavaOptionalAfter.java

@@ -1,6 +1,7 @@
 import com.google.common.base.Optional;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
 import static org.assertj.guava.api.Assertions.assertThat;
 
 public class GuavaOptional {
@@ -25,8 +26,26 @@ public class GuavaOptional {
         assertThat(opt.get()).isNotEqualTo("foo");
         assertThat(opt.get()).isNotSameAs("foo");
 
+        assertThat(opt).as("foo").isAbsent();
+        assertThat(opt).isAbsent();
+        assertThat(opt).isPresent();
+        assertThat(opt).isPresent();
+
+        //assertThat(opt.get()).isEqualTo(opt.get()); // there's a better version than contains(opt.get())
+        assertThat(opt.orNull()).isEqualTo(opt.get());
+        //assertThat(opt.get()).isEqualTo(opt.orNull()); // there's a better version than contains(opt.orNull())
+
+        assertThat(opt).contains(opt.get());
+        assertThat(opt).contains(opt.orNull());
+
+        String possibleNullString = System.getProperty("username");
+        String notNullString = "Narf";
+
         assertThat(opt).as("foo").contains("foo");
         assertThat(opt).contains("foo");
+        assertThat(opt).isEqualTo(Optional.fromNullable(null));
+        assertThat(opt).isEqualTo(Optional.fromNullable(possibleNullString));
+        assertThat(opt).isEqualTo(Optional.fromNullable(notNullString));
         assertThat(opt).isNotEqualTo(Optional.of("foo"));
         assertThat(opt).isNotEqualTo(Optional.fromNullable("foo"));
 
@@ -51,5 +70,10 @@ public class GuavaOptional {
 
         assertThat(opt).as("foo").isPresent().as("bar").isPresent();
         assertThat(opt.isPresent()).as("foo").isEqualTo(true).as("bar").isEqualTo(Boolean.FALSE);
+
+        assertThat(opt.orNull()).as("foo").isEqualTo(null).isNotNull();
+
+        org.junit.Assert.assertThat(opt, null);
+        fail("oh no!");
     }
 }

src/test/resources/inspections/GuavaOptional/GuavaOptionalBefore.java

@@ -1,6 +1,7 @@
 import com.google.common.base.Optional;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
 import static org.assertj.guava.api.Assertions.assertThat;
 
 public class GuavaOptional {
@@ -25,8 +26,26 @@ public class GuavaOptional {
         assertThat(opt.get()).isNotEqualTo("foo");
         assertThat(opt.get()).isNotSameAs("foo");
 
+        assertThat(opt.orNull()).as("foo").isEqualTo(null);
+        assertThat(opt.orNull()).isNull();
+        assertThat(opt.orNull()).isNotEqualTo(null);
+        assertThat(opt.orNull()).isNotNull();
+
+        //assertThat(opt.get()).isEqualTo(opt.get()); // there's a better version than contains(opt.get())
+        assertThat(opt.orNull()).isEqualTo(opt.get());
+        //assertThat(opt.get()).isEqualTo(opt.orNull()); // there's a better version than contains(opt.orNull())
+
+        assertThat(opt).contains(opt.get());
+        assertThat(opt).contains(opt.orNull());
+
+        String possibleNullString = System.getProperty("username");
+        String notNullString = "Narf";
+
         assertThat(opt).as("foo").isEqualTo(Optional.of("foo"));
         assertThat(opt).isEqualTo(Optional.fromNullable("foo"));
+        assertThat(opt).isEqualTo(Optional.fromNullable(null));
+        assertThat(opt).isEqualTo(Optional.fromNullable(possibleNullString));
+        assertThat(opt).isEqualTo(Optional.fromNullable(notNullString));
         assertThat(opt).isNotEqualTo(Optional.of("foo"));
         assertThat(opt).isNotEqualTo(Optional.fromNullable("foo"));
 
@@ -51,5 +70,10 @@ public class GuavaOptional {
 
         assertThat(opt.isPresent()).as("foo").isEqualTo(true).as("bar").isEqualTo(Boolean.TRUE);
         assertThat(opt.isPresent()).as("foo").isEqualTo(true).as("bar").isEqualTo(Boolean.FALSE);
+
+        assertThat(opt.orNull()).as("foo").isEqualTo(null).isNotNull();
+
+        org.junit.Assert.assertThat(opt, null);
+        fail("oh no!");
     }
 }

src/test/resources/inspections/ImplicitAssertion/ImplicitAssertionAfter.java

@@ -0,0 +1,292 @@
+import org.assertj.core.api.Condition;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+import java.util.function.Consumer;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
+import static org.assertj.guava.api.Assertions.assertThat;
+
+public class ImplicitAssertion {
+
+    private void implicitAssertion() {
+        List<String> list = new ArrayList<>();
+        List<String> moreStrings = new ArrayList<>();
+        Condition<String> stringCondition = new Condition<>();
+        Condition<List<? extends String>> listCondition = new Condition<>();
+        Consumer<String> stringConsumer = (it) -> {
+        };
+
+        String string = "foo";
+
+        com.google.common.base.Optional<String> guavaOptional = com.google.common.base.Optional.absent();
+        Optional<String> java8Optional = Optional.empty();
+
+        assertThat(string).isNotNull().isNullOrEmpty(); // could be equal to .isEmpty()
+        assertThat(string).isEmpty();
+        assertThat(string).isNotEmpty();
+        assertThat(string).hasSize(1);
+        assertThat(string).hasSizeGreaterThan(1);
+        assertThat(string).hasSizeGreaterThanOrEqualTo(1);
+        assertThat(string).hasSizeLessThan(1);
+        assertThat(string).hasSizeLessThanOrEqualTo(1);
+        assertThat(string).hasSizeBetween(1, 2);
+        assertThat(string).hasSameSizeAs(moreStrings);
+        assertThat(string).isNotNull().isEqualTo("bar");
+        assertThat(string).isNotNull().isNotEqualTo("bar");
+        assertThat(string).isNotNull().isSameAs("bar");
+        assertThat(string).isNotNull().isNotSameAs("bar");
+        assertThat(string).isNotNull().contains(string);
+        assertThat(string).isNotNull().containsOnlyOnce(string);
+        assertThat(string).isNotNull().isIn(string, "bar");
+        assertThat(string).isNotNull().isNotIn(string, "bar");
+        assertThat(string).isNotNull().doesNotContain(string, "bar");
+        assertThat(string).isNotNull().startsWith("bar");
+        assertThat(string).isNotNull().endsWith("bar");
+        assertThat(string).isNotNull().containsSequence(moreStrings);
+        assertThat(string).isNotNull().containsSubsequence(moreStrings);
+        assertThat(string).isNotNull().has(stringCondition);
+        assertThat(string).isNotNull().doesNotHave(stringCondition);
+        assertThat(string).isNotNull().is(stringCondition);
+        assertThat(string).isNotNull().isNot(stringCondition);
+        assertThat(string).hasToString(string);
+        assertThat(string).isInstanceOf(String.class);
+        assertThat(string).isNotInstanceOf(String.class);
+        assertThat(string).isExactlyInstanceOf(String.class);
+        assertThat(string).isNotExactlyInstanceOf(String.class);
+        assertThat(string).isInstanceOfAny(String.class);
+        assertThat(string).isNotInstanceOfAny(String.class);
+        assertThat(string).isInstanceOfSatisfying(String.class, stringConsumer);
+        assertThat(string).hasSameClassAs("bar");
+        assertThat(string).doesNotHaveSameClassAs("bar");
+        assertThat(string).isOfAnyClassIn(String.class, CharSequence.class);
+        assertThat(string).isNotOfAnyClassIn(String.class, CharSequence.class);
+
+        assertThat(string).isNotEmpty().isNullOrEmpty();
+        assertThat(string).isNotEmpty().isEmpty();
+        assertThat(string).isNotEmpty().isNotEmpty();
+        assertThat(string).hasSize(1);
+        assertThat(string).hasSizeGreaterThan(1);
+        assertThat(string).isNotEmpty().hasSizeGreaterThanOrEqualTo(1);
+        assertThat(string).isNotEmpty().hasSizeLessThan(1);
+        assertThat(string).isNotEmpty().hasSizeLessThanOrEqualTo(1);
+        assertThat(string).isNotEmpty().hasSizeBetween(1, 2);
+        assertThat(string).hasSameSizeAs(moreStrings);
+        assertThat(string).isNotEmpty().isEqualTo("bar");
+        assertThat(string).isNotEmpty().isNotEqualTo("bar");
+        assertThat(string).isNotEmpty().isSameAs("bar");
+        assertThat(string).isNotEmpty().isNotSameAs("bar");
+        assertThat(string).isNotEmpty().contains(string);
+        assertThat(string).isNotEmpty().containsOnlyOnce(string);
+        assertThat(string).isNotEmpty().isIn(string, "bar");
+        assertThat(string).isNotEmpty().isNotIn(string, "bar");
+        assertThat(string).isNotEmpty().doesNotContain(string, "bar");
+        assertThat(string).isNotEmpty().startsWith("bar");
+        assertThat(string).isNotEmpty().endsWith("bar");
+        assertThat(string).isNotEmpty().containsSequence(moreStrings);
+        assertThat(string).isNotEmpty().containsSubsequence(moreStrings);
+        assertThat(string).isNotEmpty().has(stringCondition);
+        assertThat(string).isNotEmpty().doesNotHave(stringCondition);
+        assertThat(string).isNotEmpty().is(stringCondition);
+        assertThat(string).isNotEmpty().isNot(stringCondition);
+        assertThat(string).isNotEmpty().hasToString(string);
+        assertThat(string).isNotEmpty().isInstanceOf(String.class);
+        assertThat(string).isNotEmpty().isNotInstanceOf(String.class);
+        assertThat(string).isNotEmpty().isExactlyInstanceOf(String.class);
+        assertThat(string).isNotEmpty().isNotExactlyInstanceOf(String.class);
+        assertThat(string).isNotEmpty().isInstanceOfAny(String.class);
+        assertThat(string).isNotEmpty().isNotInstanceOfAny(String.class);
+        assertThat(string).isNotEmpty().isInstanceOfSatisfying(String.class, stringConsumer);
+        assertThat(string).isNotEmpty().hasSameClassAs("bar");
+        assertThat(string).isNotEmpty().doesNotHaveSameClassAs("bar");
+        assertThat(string).isNotEmpty().isOfAnyClassIn(String.class, CharSequence.class);
+        assertThat(string).isNotEmpty().isNotOfAnyClassIn(String.class, CharSequence.class);
+
+        assertThat(list).isNotNull().isNullOrEmpty();
+        assertThat(list).isEmpty();
+        assertThat(list).isNotEmpty();
+        assertThat(list).hasSize(1);
+        assertThat(list).hasSizeGreaterThan(1);
+        assertThat(list).hasSizeGreaterThanOrEqualTo(1);
+        assertThat(list).hasSizeLessThan(1);
+        assertThat(list).hasSizeLessThanOrEqualTo(1);
+        assertThat(list).hasSizeBetween(1, 2);
+        assertThat(list).hasSameSizeAs(moreStrings);
+        assertThat(list).isNotNull().isEqualTo(moreStrings);
+        assertThat(list).isNotNull().isNotEqualTo(moreStrings);
+        assertThat(list).isNotNull().isSameAs(moreStrings);
+        assertThat(list).isNotNull().isNotSameAs(moreStrings);
+        assertThat(list).contains(string);
+        assertThat(list).containsOnly(string);
+        assertThat(list).containsOnlyOnce(string);
+        assertThat(list).containsOnlyNulls();
+        assertThat(list).doesNotContainNull();
+        assertThat(list).containsExactly(string, "bar");
+        assertThat(list).containsExactlyInAnyOrder(string, "bar");
+        assertThat(list).containsAnyOf(string, "bar");
+        assertThat(list).containsAll(moreStrings);
+        assertThat(list).containsExactlyInAnyOrderElementsOf(moreStrings);
+        assertThat(list).isNotNull().isIn(string, "bar");
+        assertThat(list).isNotNull().isNotIn(string, "bar");
+        assertThat(list).doesNotContain(string, "bar");
+        assertThat(list).hasSameElementsAs(moreStrings);
+        assertThat(list).containsAnyElementsOf(moreStrings);
+        assertThat(list).containsExactlyElementsOf(moreStrings);
+        assertThat(list).containsOnlyElementsOf(moreStrings);
+        assertThat(list).doesNotContainAnyElementsOf(moreStrings);
+        assertThat(list).isSubsetOf(moreStrings);
+        assertThat(list).startsWith(string, "bar");
+        assertThat(list).endsWith(string, "bar");
+        assertThat(list).doesNotHaveDuplicates();
+        assertThat(list).containsSequence(moreStrings);
+        assertThat(list).containsSubsequence(moreStrings);
+        assertThat(list).doesNotContainSequence(moreStrings);
+        assertThat(list).doesNotContainSubsequence(moreStrings);
+        assertThat(list).are(stringCondition);
+        assertThat(list).areNot(stringCondition);
+        assertThat(list).have(stringCondition);
+        assertThat(list).doNotHave(stringCondition);
+        assertThat(list).areAtLeastOne(stringCondition);
+        assertThat(list).areAtLeast(1, stringCondition);
+        assertThat(list).areAtMost(1, stringCondition);
+        assertThat(list).areExactly(1, stringCondition);
+        assertThat(list).hasOnlyOneElementSatisfying(stringConsumer);
+        assertThat(list).haveAtLeastOne(stringCondition);
+        assertThat(list).haveAtLeast(1, stringCondition);
+        assertThat(list).haveAtMost(1, stringCondition);
+        assertThat(list).haveExactly(1, stringCondition);
+        assertThat(list).hasAtLeastOneElementOfType(String.class);
+        assertThat(list).hasOnlyElementsOfType(String.class);
+        assertThat(list).hasOnlyElementsOfTypes(String.class);
+        assertThat(list).doesNotHaveAnyElementsOfTypes(String.class);
+        assertThat(list).hasOnlyElementsOfTypes(String.class);
+        assertThat(list).has(listCondition);
+        assertThat(list).doesNotHave(listCondition);
+        assertThat(list).isNotNull().is(listCondition);
+        assertThat(list).isNotNull().isNot(listCondition);
+        assertThat(list).hasToString(string);
+        assertThat(list).isInstanceOf(String.class);
+        assertThat(list).isNotInstanceOf(String.class);
+        assertThat(list).isExactlyInstanceOf(String.class);
+        assertThat(list).isNotExactlyInstanceOf(String.class);
+        assertThat(list).isInstanceOfAny(String.class);
+        assertThat(list).isNotInstanceOfAny(String.class);
+        assertThat(list).noneMatch(it -> true);
+        assertThat(list).isInstanceOfSatisfying(String.class, stringConsumer);
+        assertThat(list).hasSameClassAs("bar");
+        assertThat(list).doesNotHaveSameClassAs("bar");
+        assertThat(list).isOfAnyClassIn(String.class, CharSequence.class);
+        assertThat(list).isNotOfAnyClassIn(String.class, CharSequence.class);
+
+        assertThat(list).isNotEmpty().isNullOrEmpty();
+        assertThat(list).isNotEmpty().isEmpty();
+        assertThat(list).isNotEmpty().isNotEmpty();
+        assertThat(list).hasSize(1);
+        assertThat(list).hasSizeGreaterThan(1);
+        assertThat(list).isNotEmpty().hasSizeGreaterThanOrEqualTo(1);
+        assertThat(list).isNotEmpty().hasSizeLessThan(1);
+        assertThat(list).isNotEmpty().hasSizeLessThanOrEqualTo(1);
+        assertThat(list).isNotEmpty().hasSizeBetween(1, 2);
+        assertThat(list).hasSameSizeAs(moreStrings);
+        assertThat(list).isNotEmpty().isEqualTo(moreStrings);
+        assertThat(list).isNotEmpty().isNotEqualTo(moreStrings);
+        assertThat(list).isNotEmpty().isSameAs(moreStrings);
+        assertThat(list).isNotEmpty().isNotSameAs(moreStrings);
+        assertThat(list).isNotEmpty().contains(string);
+        assertThat(list).isNotEmpty().containsOnly(string);
+        assertThat(list).isNotEmpty().containsOnlyOnce(string);
+        assertThat(list).containsOnlyNulls();
+        assertThat(list).isNotEmpty().doesNotContainNull();
+        assertThat(list).isNotEmpty().containsExactly(string, "bar");
+        assertThat(list).isNotEmpty().containsExactlyInAnyOrder(string, "bar");
+        assertThat(list).isNotEmpty().containsAnyOf(string, "bar");
+        assertThat(list).isNotEmpty().containsAll(moreStrings);
+        assertThat(list).isNotEmpty().containsExactlyInAnyOrderElementsOf(moreStrings);
+        assertThat(list).isNotEmpty().isIn(string, "bar");
+        assertThat(list).isNotEmpty().isNotIn(string, "bar");
+        assertThat(list).isNotEmpty().doesNotContain(string, "bar");
+        assertThat(list).isNotEmpty().hasSameElementsAs(moreStrings);
+        assertThat(list).isNotEmpty().containsAnyElementsOf(moreStrings);
+        assertThat(list).isNotEmpty().containsExactlyElementsOf(moreStrings);
+        assertThat(list).isNotEmpty().containsOnlyElementsOf(moreStrings);
+        assertThat(list).isNotEmpty().doesNotContainAnyElementsOf(moreStrings);
+        assertThat(list).isNotEmpty().isSubsetOf(moreStrings);
+        assertThat(list).startsWith(string, "bar");
+        assertThat(list).endsWith(string, "bar");
+        assertThat(list).isNotEmpty().doesNotHaveDuplicates();
+        assertThat(list).isNotEmpty().containsSequence(moreStrings);
+        assertThat(list).isNotEmpty().containsSubsequence(moreStrings);
+        assertThat(list).isNotEmpty().doesNotContainSequence(moreStrings);
+        assertThat(list).isNotEmpty().doesNotContainSubsequence(moreStrings);
+        assertThat(list).isNotEmpty().are(stringCondition);
+        assertThat(list).isNotEmpty().areNot(stringCondition);
+        assertThat(list).isNotEmpty().have(stringCondition);
+        assertThat(list).isNotEmpty().doNotHave(stringCondition);
+        assertThat(list).areAtLeastOne(stringCondition);
+        assertThat(list).isNotEmpty().areAtLeast(1, stringCondition);
+        assertThat(list).isNotEmpty().areAtMost(1, stringCondition);
+        assertThat(list).isNotEmpty().areExactly(1, stringCondition);
+        assertThat(list).isNotEmpty().hasOnlyOneElementSatisfying(stringConsumer);
+        assertThat(list).haveAtLeastOne(stringCondition);
+        assertThat(list).isNotEmpty().haveAtLeast(1, stringCondition);
+        assertThat(list).isNotEmpty().haveAtMost(1, stringCondition);
+        assertThat(list).isNotEmpty().haveExactly(1, stringCondition);
+        assertThat(list).hasAtLeastOneElementOfType(String.class);
+        assertThat(list).isNotEmpty().hasOnlyElementsOfType(String.class);
+        assertThat(list).isNotEmpty().hasOnlyElementsOfTypes(String.class);
+        assertThat(list).isNotEmpty().doesNotHaveAnyElementsOfTypes(String.class);
+        assertThat(list).isNotEmpty().hasOnlyElementsOfTypes(String.class);
+        assertThat(list).isNotEmpty().has(listCondition);
+        assertThat(list).isNotEmpty().doesNotHave(listCondition);
+        assertThat(list).isNotEmpty().is(listCondition);
+        assertThat(list).isNotEmpty().isNot(listCondition);
+        assertThat(list).isNotEmpty().hasToString(string);
+        assertThat(list).isNotEmpty().isInstanceOf(String.class);
+        assertThat(list).isNotEmpty().isNotInstanceOf(String.class);
+        assertThat(list).isNotEmpty().isExactlyInstanceOf(String.class);
+        assertThat(list).isNotEmpty().isNotExactlyInstanceOf(String.class);
+        assertThat(list).isNotEmpty().isInstanceOfAny(String.class);
+        assertThat(list).isNotEmpty().isNotInstanceOfAny(String.class);
+        assertThat(list).isNotEmpty().noneMatch(it -> true);
+        assertThat(list).isNotEmpty().isInstanceOfSatisfying(String.class, stringConsumer);
+        assertThat(list).isNotEmpty().hasSameClassAs("bar");
+        assertThat(list).isNotEmpty().doesNotHaveSameClassAs("bar");
+        assertThat(list).isNotEmpty().isOfAnyClassIn(String.class, CharSequence.class);
+        assertThat(list).isNotEmpty().isNotOfAnyClassIn(String.class, CharSequence.class);
+
+
+        assertThat(java8Optional).isPresent();
+        assertThat(java8Optional).isNotPresent();
+        assertThat(java8Optional).isEmpty();
+        assertThat(java8Optional).isNotEmpty();
+        assertThat(java8Optional).contains("foo");
+        assertThat(java8Optional).containsSame("foo");
+        assertThat(java8Optional).hasValue("foo");
+        assertThat(java8Optional).containsInstanceOf(String.class);
+        assertThat(java8Optional).hasValueSatisfying(stringCondition);
+        assertThat(java8Optional).contains("foo");
+        assertThat(java8Optional).containsSame("foo");
+        assertThat(java8Optional).hasValue("foo");
+        assertThat(java8Optional).containsInstanceOf(String.class);
+        assertThat(java8Optional).hasValueSatisfying(stringCondition);
+        assertThat(java8Optional).contains("foo");
+        assertThat(java8Optional).containsSame("foo");
+        assertThat(java8Optional).hasValue("foo");
+        assertThat(java8Optional).containsInstanceOf(String.class);
+        assertThat(java8Optional).hasValueSatisfying(stringCondition);
+
+        assertThat(guavaOptional).isPresent();
+        assertThat(guavaOptional).isAbsent();
+        assertThat(guavaOptional).contains("foo");
+        assertThat(guavaOptional).extractingValue().isEqualTo("foo");
+        assertThat(guavaOptional).extractingCharSequence().isEqualTo("foo");
+        assertThat(guavaOptional).contains("foo");
+        assertThat(guavaOptional).extractingValue().isEqualTo("foo");
+        assertThat(guavaOptional).extractingCharSequence().isEqualTo("foo");
+
+        org.junit.Assert.assertThat(string, null);
+        fail("oh no!");
+    }
+}

src/test/resources/inspections/ImplicitAssertion/ImplicitAssertionBefore.java

@@ -0,0 +1,292 @@
+import org.assertj.core.api.Condition;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+import java.util.function.Consumer;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
+import static org.assertj.guava.api.Assertions.assertThat;
+
+public class ImplicitAssertion {
+
+    private void implicitAssertion() {
+        List<String> list = new ArrayList<>();
+        List<String> moreStrings = new ArrayList<>();
+        Condition<String> stringCondition = new Condition<>();
+        Condition<List<? extends String>> listCondition = new Condition<>();
+        Consumer<String> stringConsumer = (it) -> {
+        };
+
+        String string = "foo";
+
+        com.google.common.base.Optional<String> guavaOptional = com.google.common.base.Optional.absent();
+        Optional<String> java8Optional = Optional.empty();
+
+        assertThat(string).isNotNull().isNullOrEmpty(); // could be equal to .isEmpty()
+        assertThat(string).isNotNull().isEmpty();
+        assertThat(string).isNotNull().isNotEmpty();
+        assertThat(string).isNotNull().hasSize(1);
+        assertThat(string).isNotNull().hasSizeGreaterThan(1);
+        assertThat(string).isNotNull().hasSizeGreaterThanOrEqualTo(1);
+        assertThat(string).isNotNull().hasSizeLessThan(1);
+        assertThat(string).isNotNull().hasSizeLessThanOrEqualTo(1);
+        assertThat(string).isNotNull().hasSizeBetween(1, 2);
+        assertThat(string).isNotNull().hasSameSizeAs(moreStrings);
+        assertThat(string).isNotNull().isEqualTo("bar");
+        assertThat(string).isNotNull().isNotEqualTo("bar");
+        assertThat(string).isNotNull().isSameAs("bar");
+        assertThat(string).isNotNull().isNotSameAs("bar");
+        assertThat(string).isNotNull().contains(string);
+        assertThat(string).isNotNull().containsOnlyOnce(string);
+        assertThat(string).isNotNull().isIn(string, "bar");
+        assertThat(string).isNotNull().isNotIn(string, "bar");
+        assertThat(string).isNotNull().doesNotContain(string, "bar");
+        assertThat(string).isNotNull().startsWith("bar");
+        assertThat(string).isNotNull().endsWith("bar");
+        assertThat(string).isNotNull().containsSequence(moreStrings);
+        assertThat(string).isNotNull().containsSubsequence(moreStrings);
+        assertThat(string).isNotNull().has(stringCondition);
+        assertThat(string).isNotNull().doesNotHave(stringCondition);
+        assertThat(string).isNotNull().is(stringCondition);
+        assertThat(string).isNotNull().isNot(stringCondition);
+        assertThat(string).isNotNull().hasToString(string);
+        assertThat(string).isNotNull().isInstanceOf(String.class);
+        assertThat(string).isNotNull().isNotInstanceOf(String.class);
+        assertThat(string).isNotNull().isExactlyInstanceOf(String.class);
+        assertThat(string).isNotNull().isNotExactlyInstanceOf(String.class);
+        assertThat(string).isNotNull().isInstanceOfAny(String.class);
+        assertThat(string).isNotNull().isNotInstanceOfAny(String.class);
+        assertThat(string).isNotNull().isInstanceOfSatisfying(String.class, stringConsumer);
+        assertThat(string).isNotNull().hasSameClassAs("bar");
+        assertThat(string).isNotNull().doesNotHaveSameClassAs("bar");
+        assertThat(string).isNotNull().isOfAnyClassIn(String.class, CharSequence.class);
+        assertThat(string).isNotNull().isNotOfAnyClassIn(String.class, CharSequence.class);
+
+        assertThat(string).isNotEmpty().isNullOrEmpty();
+        assertThat(string).isNotEmpty().isEmpty();
+        assertThat(string).isNotEmpty().isNotEmpty();
+        assertThat(string).isNotEmpty().hasSize(1);
+        assertThat(string).isNotEmpty().hasSizeGreaterThan(1);
+        assertThat(string).isNotEmpty().hasSizeGreaterThanOrEqualTo(1);
+        assertThat(string).isNotEmpty().hasSizeLessThan(1);
+        assertThat(string).isNotEmpty().hasSizeLessThanOrEqualTo(1);
+        assertThat(string).isNotEmpty().hasSizeBetween(1, 2);
+        assertThat(string).isNotEmpty().hasSameSizeAs(moreStrings);
+        assertThat(string).isNotEmpty().isEqualTo("bar");
+        assertThat(string).isNotEmpty().isNotEqualTo("bar");
+        assertThat(string).isNotEmpty().isSameAs("bar");
+        assertThat(string).isNotEmpty().isNotSameAs("bar");
+        assertThat(string).isNotEmpty().contains(string);
+        assertThat(string).isNotEmpty().containsOnlyOnce(string);
+        assertThat(string).isNotEmpty().isIn(string, "bar");
+        assertThat(string).isNotEmpty().isNotIn(string, "bar");
+        assertThat(string).isNotEmpty().doesNotContain(string, "bar");
+        assertThat(string).isNotEmpty().startsWith("bar");
+        assertThat(string).isNotEmpty().endsWith("bar");
+        assertThat(string).isNotEmpty().containsSequence(moreStrings);
+        assertThat(string).isNotEmpty().containsSubsequence(moreStrings);
+        assertThat(string).isNotEmpty().has(stringCondition);
+        assertThat(string).isNotEmpty().doesNotHave(stringCondition);
+        assertThat(string).isNotEmpty().is(stringCondition);
+        assertThat(string).isNotEmpty().isNot(stringCondition);
+        assertThat(string).isNotEmpty().hasToString(string);
+        assertThat(string).isNotEmpty().isInstanceOf(String.class);
+        assertThat(string).isNotEmpty().isNotInstanceOf(String.class);
+        assertThat(string).isNotEmpty().isExactlyInstanceOf(String.class);
+        assertThat(string).isNotEmpty().isNotExactlyInstanceOf(String.class);
+        assertThat(string).isNotEmpty().isInstanceOfAny(String.class);
+        assertThat(string).isNotEmpty().isNotInstanceOfAny(String.class);
+        assertThat(string).isNotEmpty().isInstanceOfSatisfying(String.class, stringConsumer);
+        assertThat(string).isNotEmpty().hasSameClassAs("bar");
+        assertThat(string).isNotEmpty().doesNotHaveSameClassAs("bar");
+        assertThat(string).isNotEmpty().isOfAnyClassIn(String.class, CharSequence.class);
+        assertThat(string).isNotEmpty().isNotOfAnyClassIn(String.class, CharSequence.class);
+
+        assertThat(list).isNotNull().isNullOrEmpty();
+        assertThat(list).isNotNull().isEmpty();
+        assertThat(list).isNotNull().isNotEmpty();
+        assertThat(list).isNotNull().hasSize(1);
+        assertThat(list).isNotNull().hasSizeGreaterThan(1);
+        assertThat(list).isNotNull().hasSizeGreaterThanOrEqualTo(1);
+        assertThat(list).isNotNull().hasSizeLessThan(1);
+        assertThat(list).isNotNull().hasSizeLessThanOrEqualTo(1);
+        assertThat(list).isNotNull().hasSizeBetween(1, 2);
+        assertThat(list).isNotNull().hasSameSizeAs(moreStrings);
+        assertThat(list).isNotNull().isEqualTo(moreStrings);
+        assertThat(list).isNotNull().isNotEqualTo(moreStrings);
+        assertThat(list).isNotNull().isSameAs(moreStrings);
+        assertThat(list).isNotNull().isNotSameAs(moreStrings);
+        assertThat(list).isNotNull().contains(string);
+        assertThat(list).isNotNull().containsOnly(string);
+        assertThat(list).isNotNull().containsOnlyOnce(string);
+        assertThat(list).isNotNull().containsOnlyNulls();
+        assertThat(list).isNotNull().doesNotContainNull();
+        assertThat(list).isNotNull().containsExactly(string, "bar");
+        assertThat(list).isNotNull().containsExactlyInAnyOrder(string, "bar");
+        assertThat(list).isNotNull().containsAnyOf(string, "bar");
+        assertThat(list).isNotNull().containsAll(moreStrings);
+        assertThat(list).isNotNull().containsExactlyInAnyOrderElementsOf(moreStrings);
+        assertThat(list).isNotNull().isIn(string, "bar");
+        assertThat(list).isNotNull().isNotIn(string, "bar");
+        assertThat(list).isNotNull().doesNotContain(string, "bar");
+        assertThat(list).isNotNull().hasSameElementsAs(moreStrings);
+        assertThat(list).isNotNull().containsAnyElementsOf(moreStrings);
+        assertThat(list).isNotNull().containsExactlyElementsOf(moreStrings);
+        assertThat(list).isNotNull().containsOnlyElementsOf(moreStrings);
+        assertThat(list).isNotNull().doesNotContainAnyElementsOf(moreStrings);
+        assertThat(list).isNotNull().isSubsetOf(moreStrings);
+        assertThat(list).isNotNull().startsWith(string, "bar");
+        assertThat(list).isNotNull().endsWith(string, "bar");
+        assertThat(list).isNotNull().doesNotHaveDuplicates();
+        assertThat(list).isNotNull().containsSequence(moreStrings);
+        assertThat(list).isNotNull().containsSubsequence(moreStrings);
+        assertThat(list).isNotNull().doesNotContainSequence(moreStrings);
+        assertThat(list).isNotNull().doesNotContainSubsequence(moreStrings);
+        assertThat(list).isNotNull().are(stringCondition);
+        assertThat(list).isNotNull().areNot(stringCondition);
+        assertThat(list).isNotNull().have(stringCondition);
+        assertThat(list).isNotNull().doNotHave(stringCondition);
+        assertThat(list).isNotNull().areAtLeastOne(stringCondition);
+        assertThat(list).isNotNull().areAtLeast(1, stringCondition);
+        assertThat(list).isNotNull().areAtMost(1, stringCondition);
+        assertThat(list).isNotNull().areExactly(1, stringCondition);
+        assertThat(list).isNotNull().hasOnlyOneElementSatisfying(stringConsumer);
+        assertThat(list).isNotNull().haveAtLeastOne(stringCondition);
+        assertThat(list).isNotNull().haveAtLeast(1, stringCondition);
+        assertThat(list).isNotNull().haveAtMost(1, stringCondition);
+        assertThat(list).isNotNull().haveExactly(1, stringCondition);
+        assertThat(list).isNotNull().hasAtLeastOneElementOfType(String.class);
+        assertThat(list).isNotNull().hasOnlyElementsOfType(String.class);
+        assertThat(list).isNotNull().hasOnlyElementsOfTypes(String.class);
+        assertThat(list).isNotNull().doesNotHaveAnyElementsOfTypes(String.class);
+        assertThat(list).isNotNull().hasOnlyElementsOfTypes(String.class);
+        assertThat(list).isNotNull().has(listCondition);
+        assertThat(list).isNotNull().doesNotHave(listCondition);
+        assertThat(list).isNotNull().is(listCondition);
+        assertThat(list).isNotNull().isNot(listCondition);
+        assertThat(list).isNotNull().hasToString(string);
+        assertThat(list).isNotNull().isInstanceOf(String.class);
+        assertThat(list).isNotNull().isNotInstanceOf(String.class);
+        assertThat(list).isNotNull().isExactlyInstanceOf(String.class);
+        assertThat(list).isNotNull().isNotExactlyInstanceOf(String.class);
+        assertThat(list).isNotNull().isInstanceOfAny(String.class);
+        assertThat(list).isNotNull().isNotInstanceOfAny(String.class);
+        assertThat(list).isNotNull().noneMatch(it -> true);
+        assertThat(list).isNotNull().isInstanceOfSatisfying(String.class, stringConsumer);
+        assertThat(list).isNotNull().hasSameClassAs("bar");
+        assertThat(list).isNotNull().doesNotHaveSameClassAs("bar");
+        assertThat(list).isNotNull().isOfAnyClassIn(String.class, CharSequence.class);
+        assertThat(list).isNotNull().isNotOfAnyClassIn(String.class, CharSequence.class);
+
+        assertThat(list).isNotEmpty().isNullOrEmpty();
+        assertThat(list).isNotEmpty().isEmpty();
+        assertThat(list).isNotEmpty().isNotEmpty();
+        assertThat(list).isNotEmpty().hasSize(1);
+        assertThat(list).isNotEmpty().hasSizeGreaterThan(1);
+        assertThat(list).isNotEmpty().hasSizeGreaterThanOrEqualTo(1);
+        assertThat(list).isNotEmpty().hasSizeLessThan(1);
+        assertThat(list).isNotEmpty().hasSizeLessThanOrEqualTo(1);
+        assertThat(list).isNotEmpty().hasSizeBetween(1, 2);
+        assertThat(list).isNotEmpty().hasSameSizeAs(moreStrings);
+        assertThat(list).isNotEmpty().isEqualTo(moreStrings);
+        assertThat(list).isNotEmpty().isNotEqualTo(moreStrings);
+        assertThat(list).isNotEmpty().isSameAs(moreStrings);
+        assertThat(list).isNotEmpty().isNotSameAs(moreStrings);
+        assertThat(list).isNotEmpty().contains(string);
+        assertThat(list).isNotEmpty().containsOnly(string);
+        assertThat(list).isNotEmpty().containsOnlyOnce(string);
+        assertThat(list).isNotEmpty().containsOnlyNulls();
+        assertThat(list).isNotEmpty().doesNotContainNull();
+        assertThat(list).isNotEmpty().containsExactly(string, "bar");
+        assertThat(list).isNotEmpty().containsExactlyInAnyOrder(string, "bar");
+        assertThat(list).isNotEmpty().containsAnyOf(string, "bar");
+        assertThat(list).isNotEmpty().containsAll(moreStrings);
+        assertThat(list).isNotEmpty().containsExactlyInAnyOrderElementsOf(moreStrings);
+        assertThat(list).isNotEmpty().isIn(string, "bar");
+        assertThat(list).isNotEmpty().isNotIn(string, "bar");
+        assertThat(list).isNotEmpty().doesNotContain(string, "bar");
+        assertThat(list).isNotEmpty().hasSameElementsAs(moreStrings);
+        assertThat(list).isNotEmpty().containsAnyElementsOf(moreStrings);
+        assertThat(list).isNotEmpty().containsExactlyElementsOf(moreStrings);
+        assertThat(list).isNotEmpty().containsOnlyElementsOf(moreStrings);
+        assertThat(list).isNotEmpty().doesNotContainAnyElementsOf(moreStrings);
+        assertThat(list).isNotEmpty().isSubsetOf(moreStrings);
+        assertThat(list).isNotEmpty().startsWith(string, "bar");
+        assertThat(list).isNotEmpty().endsWith(string, "bar");
+        assertThat(list).isNotEmpty().doesNotHaveDuplicates();
+        assertThat(list).isNotEmpty().containsSequence(moreStrings);
+        assertThat(list).isNotEmpty().containsSubsequence(moreStrings);
+        assertThat(list).isNotEmpty().doesNotContainSequence(moreStrings);
+        assertThat(list).isNotEmpty().doesNotContainSubsequence(moreStrings);
+        assertThat(list).isNotEmpty().are(stringCondition);
+        assertThat(list).isNotEmpty().areNot(stringCondition);
+        assertThat(list).isNotEmpty().have(stringCondition);
+        assertThat(list).isNotEmpty().doNotHave(stringCondition);
+        assertThat(list).isNotEmpty().areAtLeastOne(stringCondition);
+        assertThat(list).isNotEmpty().areAtLeast(1, stringCondition);
+        assertThat(list).isNotEmpty().areAtMost(1, stringCondition);
+        assertThat(list).isNotEmpty().areExactly(1, stringCondition);
+        assertThat(list).isNotEmpty().hasOnlyOneElementSatisfying(stringConsumer);
+        assertThat(list).isNotEmpty().haveAtLeastOne(stringCondition);
+        assertThat(list).isNotEmpty().haveAtLeast(1, stringCondition);
+        assertThat(list).isNotEmpty().haveAtMost(1, stringCondition);
+        assertThat(list).isNotEmpty().haveExactly(1, stringCondition);
+        assertThat(list).isNotEmpty().hasAtLeastOneElementOfType(String.class);
+        assertThat(list).isNotEmpty().hasOnlyElementsOfType(String.class);
+        assertThat(list).isNotEmpty().hasOnlyElementsOfTypes(String.class);
+        assertThat(list).isNotEmpty().doesNotHaveAnyElementsOfTypes(String.class);
+        assertThat(list).isNotEmpty().hasOnlyElementsOfTypes(String.class);
+        assertThat(list).isNotEmpty().has(listCondition);
+        assertThat(list).isNotEmpty().doesNotHave(listCondition);
+        assertThat(list).isNotEmpty().is(listCondition);
+        assertThat(list).isNotEmpty().isNot(listCondition);
+        assertThat(list).isNotEmpty().hasToString(string);
+        assertThat(list).isNotEmpty().isInstanceOf(String.class);
+        assertThat(list).isNotEmpty().isNotInstanceOf(String.class);
+        assertThat(list).isNotEmpty().isExactlyInstanceOf(String.class);
+        assertThat(list).isNotEmpty().isNotExactlyInstanceOf(String.class);
+        assertThat(list).isNotEmpty().isInstanceOfAny(String.class);
+        assertThat(list).isNotEmpty().isNotInstanceOfAny(String.class);
+        assertThat(list).isNotEmpty().noneMatch(it -> true);
+        assertThat(list).isNotEmpty().isInstanceOfSatisfying(String.class, stringConsumer);
+        assertThat(list).isNotEmpty().hasSameClassAs("bar");
+        assertThat(list).isNotEmpty().doesNotHaveSameClassAs("bar");
+        assertThat(list).isNotEmpty().isOfAnyClassIn(String.class, CharSequence.class);
+        assertThat(list).isNotEmpty().isNotOfAnyClassIn(String.class, CharSequence.class);
+
+
+        assertThat(java8Optional).isNotNull().isPresent();
+        assertThat(java8Optional).isNotNull().isNotPresent();
+        assertThat(java8Optional).isNotNull().isEmpty();
+        assertThat(java8Optional).isNotNull().isNotEmpty();
+        assertThat(java8Optional).isNotNull().contains("foo");
+        assertThat(java8Optional).isNotNull().containsSame("foo");
+        assertThat(java8Optional).isNotNull().hasValue("foo");
+        assertThat(java8Optional).isNotNull().containsInstanceOf(String.class);
+        assertThat(java8Optional).isNotNull().hasValueSatisfying(stringCondition);
+        assertThat(java8Optional).isPresent().contains("foo");
+        assertThat(java8Optional).isPresent().containsSame("foo");
+        assertThat(java8Optional).isPresent().hasValue("foo");
+        assertThat(java8Optional).isPresent().containsInstanceOf(String.class);
+        assertThat(java8Optional).isPresent().hasValueSatisfying(stringCondition);
+        assertThat(java8Optional).isNotEmpty().contains("foo");
+        assertThat(java8Optional).isNotEmpty().containsSame("foo");
+        assertThat(java8Optional).isNotEmpty().hasValue("foo");
+        assertThat(java8Optional).isNotEmpty().containsInstanceOf(String.class);
+        assertThat(java8Optional).isNotEmpty().hasValueSatisfying(stringCondition);
+
+        assertThat(guavaOptional).isNotNull().isPresent();
+        assertThat(guavaOptional).isNotNull().isAbsent();
+        assertThat(guavaOptional).isNotNull().contains("foo");
+        assertThat(guavaOptional).isNotNull().extractingValue().isEqualTo("foo");
+        assertThat(guavaOptional).isNotNull().extractingCharSequence().isEqualTo("foo");
+        assertThat(guavaOptional).isPresent().contains("foo");
+        assertThat(guavaOptional).isPresent().extractingValue().isEqualTo("foo");
+        assertThat(guavaOptional).isPresent().extractingCharSequence().isEqualTo("foo");
+
+        org.junit.Assert.assertThat(string, null);
+        fail("oh no!");
+    }
+}

src/test/resources/inspections/InstanceOf/InstanceOfAfter.java

@@ -1,4 +1,5 @@
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
 
 public class InstanceOf {
 
@@ -21,5 +22,8 @@ public class InstanceOf {
 
         assertThat(object).as("foo").isInstanceOf(Boolean.class).as("bar").isInstanceOf(Boolean.class);
         assertThat(object instanceof Boolean).as("foo").isEqualTo(Boolean.TRUE).as("bar").isEqualTo(false);
+
+        org.junit.Assert.assertThat(object, null);
+        fail("oh no!");
     }
 }

src/test/resources/inspections/InstanceOf/InstanceOfBefore.java

@@ -1,4 +1,5 @@
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
 
 public class InstanceOf {
 
@@ -21,5 +22,8 @@ public class InstanceOf {
 
         assertThat(object instanceof Boolean).as("foo").isEqualTo(Boolean.TRUE).as("bar").isEqualTo(true);
         assertThat(object instanceof Boolean).as("foo").isEqualTo(Boolean.TRUE).as("bar").isEqualTo(false);
+
+        org.junit.Assert.assertThat(object, null);
+        fail("oh no!");
     }
 }

src/test/resources/inspections/InvertedBooleanCondition/InvertedBooleanConditionAfter.java

@@ -1,4 +1,5 @@
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
 
 public class InvertedBooleanCondition {
 
@@ -35,5 +36,8 @@ public class InvertedBooleanCondition {
 
         assertThat(primitive).as("foo").isFalse().as("bar").isFalse();
         assertThat(primitive).as("foo").isFalse().as("bar").isTrue();
+
+        org.junit.Assert.assertThat(object, null);
+        fail("oh no!");
     }
 }

src/test/resources/inspections/InvertedBooleanCondition/InvertedBooleanConditionBefore.java

@@ -1,4 +1,5 @@
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
 
 public class InvertedBooleanCondition {
 
@@ -35,5 +36,8 @@ public class InvertedBooleanCondition {
 
         assertThat(!primitive).as("foo").isEqualTo(Boolean.TRUE).as("bar").isNotEqualTo(false);
         assertThat(!primitive).as("foo").isEqualTo(Boolean.TRUE).as("bar").isNotEqualTo(true);
+
+        org.junit.Assert.assertThat(object, null);
+        fail("oh no!");
     }
 }

src/test/resources/inspections/JUnitAssertToAssertJ/JUnitAssertToAssertJInspectionAfter.java

@@ -1,12 +1,18 @@
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assumptions.assumeThat;
 import static org.assertj.core.data.Offset.offset;
 import static org.junit.Assert.*;
+import static org.junit.Assume.*;
 
 public class JUnitAssertToAssertJ {
 
     private void jUnitAssertToAssertJ() {
         String foo = "foo";
         String bar = "bar";
+        int someInt = 1;
+        double someDouble = 1.0;
+        float someFloat = 1.0f;
+
         assertThat(foo == "foo").isTrue();
         assertThat(foo == "foo").as("oh no!").isTrue();
         assertThat(foo == "bar").isFalse();
@@ -52,5 +58,35 @@ public class JUnitAssertToAssertJ {
         assertThat(new double[1]).as("array equals").containsExactly(new double[2], offset(1.0));
         assertThat(new float[1]).containsExactly(new float[2], offset(1.0f));
         assertThat(new float[1]).as("array equals").containsExactly(new float[2], offset(1.0f));
+
+        assertThat(foo).isEqualTo("bar");
+        assertThat(bar).as("equals").isEqualTo("foo");
+        assertThat(bar).isNotEqualTo("foo");
+        assertThat(foo).as("equals").isNotEqualTo("bar");
+
+        assertThat(someInt).isEqualTo(2);
+        assertThat(someDouble).isCloseTo(2.0, offset(0.1));
+        assertThat(someDouble).as("equals").isEqualTo(1.0);
+        assertThat(someDouble).as("equals").isCloseTo(1.0, offset(0.1));
+        assertThat(someFloat).isEqualTo(1.0f);
+        assertThat(someFloat).isCloseTo(2.0f, offset(0.1f));
+
+        fail();
+        fail("oh no!")
+    }
+
+    private void jUnitAssumeToAssertJ() {
+        String foo = "foo";
+        String bar = "bar";
+        assumeThat(foo == "foo").isTrue();
+        assumeThat(foo == "foo").as("oh no!").isTrue();
+        assumeThat(foo == "bar").isFalse();
+        assumeThat(foo == "bar").as("boom!").isFalse();
+
+        assumeThat(foo).isNotNull();
+        assumeNotNull(foo, bar);
+
+        assumeThat(new IllegalArgumentException()).doesNotThrowAnyException();
+        assumeThat(new IllegalArgumentException()).as("oh no!").doesNotThrowAnyException();
     }
 }

src/test/resources/inspections/JUnitAssertToAssertJ/JUnitAssertToAssertJInspectionBefore.java

@@ -1,10 +1,15 @@
 import static org.junit.Assert.*;
+import static org.junit.Assume.*;
 
 public class JUnitAssertToAssertJ {
 
     private void jUnitAssertToAssertJ() {
         String foo = "foo";
         String bar = "bar";
+        int someInt = 1;
+        double someDouble = 1.0;
+        float someFloat = 1.0f;
+
         assertTrue(foo == "foo");
         assertTrue("oh no!", foo == "foo");
         assertFalse(foo == "bar");
@@ -50,5 +55,35 @@ public class JUnitAssertToAssertJ {
         assertArrayEquals("array equals", new double[2], new double[1], 1.0);
         assertArrayEquals(new float[2], new float[1], 1.0f);
         assertArrayEquals("array equals", new float[2], new float[1], 1.0f);
+
+        assertEquals("bar", foo);
+        assertEquals("equals", bar, "foo");
+        assertNotEquals(bar, "foo");
+        assertNotEquals("equals", "bar", foo);
+
+        assertEquals(someInt, 2);
+        assertEquals(someDouble, 2.0, 0.1);
+        assertEquals("equals",1.0, someDouble);
+        assertEquals("equals",1.0, someDouble, 0.1);
+        assertEquals(1.0f, someFloat);
+        assertEquals(someFloat, 2.0f, 0.1f);
+
+        fail();
+        fail("oh no!")
+    }
+
+    private void jUnitAssumeToAssertJ() {
+        String foo = "foo";
+        String bar = "bar";
+        assumeTrue(foo == "foo");
+        assumeTrue("oh no!", foo == "foo");
+        assumeFalse(foo == "bar");
+        assumeFalse("boom!", foo == "bar");
+
+        assumeNotNull(foo);
+        assumeNotNull(foo, bar);
+
+        assumeNoException(new IllegalArgumentException());
+        assumeNoException("oh no!", new IllegalArgumentException());
     }
 }

src/test/resources/inspections/Java8Optional/Java8OptionalAfter.java

@@ -1,6 +1,7 @@
 import java.util.Optional;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
 
 public class Java8Optional {
 
@@ -24,8 +25,26 @@ public class Java8Optional {
         assertThat(opt.get()).isNotEqualTo("foo");
         assertThat(opt.get()).isNotSameAs("foo");
 
+        assertThat(opt).as("foo").isNotPresent();
+        assertThat(opt).isNotPresent();
+        assertThat(opt).isPresent();
+        assertThat(opt).isPresent();
+
+        //assertThat(opt.get()).isEqualTo(opt.get()); // there's a better version than contains(opt.get())
+        assertThat(opt.orElse(null)).isEqualTo(opt.get());
+        //assertThat(opt.get()).isEqualTo(opt.orElse(null)); // there's a better version than contains(opt.orElse(null))
+
+        assertThat(opt).contains(opt.get());
+        assertThat(opt).contains(opt.orElse(null));
+
+        String possibleNullString = System.getProperty("username");
+        String notNullString = "Narf";
+
         assertThat(opt).as("foo").contains("foo");
         assertThat(opt).contains("foo");
+        assertThat(opt).isEqualTo(Optional.ofNullable(null));
+        assertThat(opt).isEqualTo(Optional.ofNullable(possibleNullString));
+        assertThat(opt).isEqualTo(Optional.ofNullable(notNullString));
         assertThat(opt).isNotEqualTo(Optional.of("foo"));
         assertThat(opt).isNotEqualTo(Optional.ofNullable("foo"));
 
@@ -36,5 +55,12 @@ public class Java8Optional {
         assertThat(opt.isPresent()).as("foo").isEqualTo(false).as("bar").isTrue();
 
         assertThat(opt.get()).isEqualTo("foo").isSameAs("foo").isNotEqualTo("foo").isNotSameAs("foo");
+
+        assertThat(opt.orElse("foo")).as("foo").isEqualTo(null);
+
+        assertThat(opt.orElse(null)).as("foo").isEqualTo(null).isNotNull();
+
+        org.junit.Assert.assertThat(opt, null);
+        fail("oh no!");
     }
 }

src/test/resources/inspections/Java8Optional/Java8OptionalBefore.java

@@ -1,6 +1,7 @@
 import java.util.Optional;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
 
 public class Java8Optional {
 
@@ -24,8 +25,26 @@ public class Java8Optional {
         assertThat(opt.get()).isNotEqualTo("foo");
         assertThat(opt.get()).isNotSameAs("foo");
 
+        assertThat(opt.orElse(null)).as("foo").isEqualTo(null);
+        assertThat(opt.orElse(null)).isNull();
+        assertThat(opt.orElse(null)).isNotEqualTo(null);
+        assertThat(opt.orElse(null)).isNotNull();
+
+        //assertThat(opt.get()).isEqualTo(opt.get()); // there's a better version than contains(opt.get())
+        assertThat(opt.orElse(null)).isEqualTo(opt.get());
+        //assertThat(opt.get()).isEqualTo(opt.orElse(null)); // there's a better version than contains(opt.orElse(null))
+
+        assertThat(opt).contains(opt.get());
+        assertThat(opt).contains(opt.orElse(null));
+
+        String possibleNullString = System.getProperty("username");
+        String notNullString = "Narf";
+
         assertThat(opt).as("foo").isEqualTo(Optional.of("foo"));
         assertThat(opt).isEqualTo(Optional.ofNullable("foo"));
+        assertThat(opt).isEqualTo(Optional.ofNullable(null));
+        assertThat(opt).isEqualTo(Optional.ofNullable(possibleNullString));
+        assertThat(opt).isEqualTo(Optional.ofNullable(notNullString));
         assertThat(opt).isNotEqualTo(Optional.of("foo"));
         assertThat(opt).isNotEqualTo(Optional.ofNullable("foo"));
 
@@ -36,5 +55,12 @@ public class Java8Optional {
         assertThat(opt.isPresent()).as("foo").isEqualTo(false).as("bar").isTrue();
 
         assertThat(opt.get()).isEqualTo("foo").isSameAs("foo").isNotEqualTo("foo").isNotSameAs("foo");
+
+        assertThat(opt.orElse("foo")).as("foo").isEqualTo(null);
+
+        assertThat(opt.orElse(null)).as("foo").isEqualTo(null).isNotNull();
+
+        org.junit.Assert.assertThat(opt, null);
+        fail("oh no!");
     }
 }

src/test/resources/inspections/JoinStatements/JoinStatementsAfter.java

@@ -1,6 +1,7 @@
 import java.util.*;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
 
 public class JoinStatements {
 
@@ -24,21 +25,28 @@ public class JoinStatements {
                 .doesNotContain("foobar");
 
         assertThat("narf").isNotEqualTo("puit");
-        assertThat(list).as("bar").contains("barbar").as("foo").hasSize(2);
+        assertThat(list).as("bar").contains("barbar")
+                .as("foo").hasSize(2);
         assertThat(list).as("evil").extracting(String::length).contains(2);
 
         assertThat(list).as("bar").contains("barbar");
         assertThat(otherList).contains("puit");
         assertThat(list).as("foo").hasSize(2);
         if (true) {
-            assertThat(list).doesNotContain("narf").as("bar").contains("barbar");
+            assertThat(list).doesNotContain("narf")
+                    .as("bar").contains("barbar");
         }
-        assertThat(list.get(0)).isNotEmpty().hasSize(3).isEqualTo("bar");
+        assertThat(list.get(0)).isNotEmpty()
+                .hasSize(3)
+                .isEqualTo("bar");
 
         assertThat(otherList.get(0)).isNotEmpty();
         assertThat(list.get(0)).hasSize(3);
 
-        assertThat(list.get(0) + "foo").isEqualTo("bar").doesNotStartWith("foo");
+        assertThat(list.get(0) + "foo").isNotNull()
+                // hey, a comment mixed with line breaks due to too many joins
+                .isEqualTo("bar")
+                .doesNotStartWith("foo");
 
         assertThat(otherList.get(0) + "foo").isEqualTo("bar");
         assertThat(list.get(0) + "foo").doesNotStartWith("foo");
@@ -48,5 +56,17 @@ public class JoinStatements {
         assertThat(iterator.next()).isEqualTo("bar");
         assertThat(iterator.next().toLowerCase()).isEqualTo("foo");
         assertThat(iterator.next().toLowerCase()).isEqualTo("bar");
+        assertThat(iterator.next() + "bar").isEqualTo("foobar");
+        assertThat(iterator.next() + "bar").isEqualTo("barbar");
+        int i = 0;
+        assertThat(++i).isEqualTo(1);
+        assertThat(++i).isEqualTo(2);
+        assertThat(list.get(i++).toLowerCase()).isEqualTo("foo");
+        assertThat(list.get(i++).toLowerCase()).isEqualTo("foo");
+        assertThat(list.get(--i)).isEqualTo("foo");
+        assertThat(list.get(--i)).isEqualTo("foo");
+
+        org.junit.Assert.assertThat(list, null);
+        fail("oh no!");
     }
 }

src/test/resources/inspections/JoinStatements/JoinStatementsBefore.java

@@ -1,6 +1,7 @@
 import java.util.*;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
 
 public class JoinStatements {
 
@@ -39,6 +40,8 @@ public class JoinStatements {
         assertThat(otherList.get(0)).isNotEmpty();
         assertThat(list.get(0)).hasSize(3);
 
+        assertThat(list.get(0) + "foo").isNotNull();
+        // hey, a comment mixed with line breaks due to too many joins
         assertThat(list.get(0) + "foo").isEqualTo("bar");
         assertThat(list.get(0) + "foo").doesNotStartWith("foo");
 
@@ -50,5 +53,17 @@ public class JoinStatements {
         assertThat(iterator.next()).isEqualTo("bar");
         assertThat(iterator.next().toLowerCase()).isEqualTo("foo");
         assertThat(iterator.next().toLowerCase()).isEqualTo("bar");
+        assertThat(iterator.next() + "bar").isEqualTo("foobar");
+        assertThat(iterator.next() + "bar").isEqualTo("barbar");
+        int i = 0;
+        assertThat(++i).isEqualTo(1);
+        assertThat(++i).isEqualTo(2);
+        assertThat(list.get(i++).toLowerCase()).isEqualTo("foo");
+        assertThat(list.get(i++).toLowerCase()).isEqualTo("foo");
+        assertThat(list.get(--i)).isEqualTo("foo");
+        assertThat(list.get(--i)).isEqualTo("foo");
+
+        org.junit.Assert.assertThat(list, null);
+        fail("oh no!");
     }
 }

src/test/resources/inspections/JoinVarArgsContains/JoinVarArgsContainsAfter.java

@@ -0,0 +1,22 @@
+import java.util.*;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
+
+public class JoinVarArgsContains {
+
+    private void joinVarArgsContains() {
+        List<String> list = new ArrayList<>();
+
+        assertThat(list).contains("foo", "bar", "etc").hasSize(2);
+        assertThat(list).contains("foo").as("narf").contains("bar");
+        assertThat(list).doesNotContain("foo", "bar");
+        assertThat(list).containsOnlyOnce("foo", "etc") // will we lose this comment?
+                .hasSize(2).contains("bar", "narf", "1", "2", "3").doesNotContain("puit", "Jens Stoltenberg is a war-monger", "and an atomic playboy") /* inline */; // the final comment
+
+        assertThat(list).contains("foo").doesNotContain("bar").containsOnlyOnce("narf");
+
+        org.junit.Assert.assertThat(list, null);
+        fail("oh no!");
+    }
+}

src/test/resources/inspections/JoinVarArgsContains/JoinVarArgsContainsBefore.java

@@ -0,0 +1,28 @@
+import java.util.*;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
+
+public class JoinVarArgsContains {
+
+    private void joinVarArgsContains() {
+        List<String> list = new ArrayList<>();
+
+        assertThat(list).contains("foo").contains(/* foo */ "bar" /* bar */).hasSize(2).contains("etc");
+        assertThat(list).contains("foo").as("narf").contains("bar");
+        assertThat(list).doesNotContain("foo").doesNotContain("bar");
+        assertThat(list).containsOnlyOnce()
+                .containsOnlyOnce("foo") // will we lose this comment?
+                .hasSize(2) // this is part of the contains("bar")
+                .contains("bar").containsOnlyOnce("etc") /* where does this go? */
+                .contains("narf") // what about this one?
+                .doesNotContain("puit", "Jens Stoltenberg is a war-monger")
+                .doesNotContain("and an atomic playboy")
+                .contains("1", "2", "3") /* inline */; // the final comment
+
+        assertThat(list).contains("foo").doesNotContain("bar").containsOnlyOnce("narf");
+
+        org.junit.Assert.assertThat(list, null);
+        fail("oh no!");
+    }
+}

src/test/resources/inspections/ObjectExpression/ObjectExpressionAfter.java

@@ -0,0 +1,31 @@
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
+
+public class ObjectExpression {
+
+    private void objectExpression() {
+        Integer object = 1;
+        Integer otherObject = 1;
+        boolean foo = false;
+
+        assertThat(object).hasToString("foo");
+        assertThat(object.toString()).isNotEqualTo("foo");
+
+        assertThat(object).hasSameHashCodeAs(otherObject);
+        assertThat(object.hashCode()).isEqualTo(123);
+
+        assertThat(object).as("doh!").isEqualTo(otherObject);
+        assertThat(object).isEqualTo(otherObject);
+        assertThat(object).isEqualTo(otherObject);
+        assertThat(object).isNotEqualTo(otherObject);
+        assertThat(object).isNotEqualTo(otherObject);
+        assertThat(object).isNotEqualTo(otherObject);
+
+        assertThat(object.equals(otherObject)).isEqualTo(foo);
+
+        assertThat(object).as("doh!").isEqualTo(otherObject).isEqualTo(otherObject);
+
+        org.junit.Assert.assertThat(foo, null);
+        fail("oh no!");
+    }
+}

src/test/resources/inspections/ObjectExpression/ObjectExpressionBefore.java

@@ -0,0 +1,31 @@
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
+
+public class ObjectExpression {
+
+    private void objectExpression() {
+        Integer object = 1;
+        Integer otherObject = 1;
+        boolean foo = false;
+
+        assertThat(object.toString()).isEqualTo("foo");
+        assertThat(object.toString()).isNotEqualTo("foo");
+
+        assertThat(object.hashCode()).isEqualTo(otherObject.hashCode());
+        assertThat(object.hashCode()).isEqualTo(123);
+
+        assertThat(object.equals(otherObject)).as("doh!").isTrue();
+        assertThat(object.equals(otherObject)).isEqualTo(true);
+        assertThat(object.equals(otherObject)).isNotEqualTo(false);
+        assertThat(object.equals(otherObject)).isFalse();
+        assertThat(object.equals(otherObject)).isEqualTo(false);
+        assertThat(object.equals(otherObject)).isNotEqualTo(true);
+
+        assertThat(object.equals(otherObject)).isEqualTo(foo);
+
+        assertThat(object.equals(otherObject)).as("doh!").isTrue().isEqualTo(true);
+
+        org.junit.Assert.assertThat(foo, null);
+        fail("oh no!");
+    }
+}

src/test/resources/inspections/ObjectIsNullOrNotNull/ObjectIsNullOrNotNullAfter.java

@@ -1,4 +1,5 @@
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
 
 public class ObjectIsNull {
 
@@ -13,5 +14,8 @@ public class ObjectIsNull {
 
         assertThat(new Object()).as("foo").isNotNull().as("bar").isEqualTo(new Object()).as("etc").isNull();
         assertThat(new Object()).as("foo").isEqualTo(null).as("bar").isEqualTo(new Object()).as("etc").isNotNull();
+
+        org.junit.Assert.assertThat("foo", null);
+        fail("oh no!");
     }
 }

src/test/resources/inspections/ObjectIsNullOrNotNull/ObjectIsNullOrNotNullBefore.java

@@ -1,4 +1,5 @@
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
 
 public class ObjectIsNull {
 
@@ -13,5 +14,8 @@ public class ObjectIsNull {
 
         assertThat(new Object()).as("foo").isNotEqualTo(null).as("bar").isEqualTo(new Object()).as("etc").isEqualTo(null);
         assertThat(new Object()).as("foo").isEqualTo(null).as("bar").isEqualTo(new Object()).as("etc").isNotEqualTo(null);
+
+        org.junit.Assert.assertThat("foo", null);
+        fail("oh no!");
     }
 }

src/test/resources/inspections/Size/SizeAfter.java

@@ -1,6 +1,7 @@
 import java.util.ArrayList;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
 
 public class Size {
 
@@ -99,5 +100,12 @@ public class Size {
         assertThat(stringBuilder.length()).as("foo").isEqualTo(0).isZero().as("bar").isNotZero().isEqualTo(10);
 
         assertThat(stringBuilder).as("foo").isNotEmpty().hasSize(2).as("bar").hasSameSizeAs(otherList).hasSameSizeAs(array);
+
+        int foo = 1;
+        assertThat(foo).isEqualTo(0);
+        assertThat(string.length()).isPositive();
+
+        org.junit.Assert.assertThat(string, null);
+        fail("oh no!");
     }
 }