Fixed a bug in AssertThatBinaryExpression inspection for assertThat(null != expression) and related that would not correctly invert the condition on transformation.

README.md

@@ -567,6 +567,8 @@ Feel free to use the code (in package ```de.platon42.intellij.jupiter```) for yo
 #### V1.6 (unreleased)
 - Really fixed AssertThatGuavaOptional inspections to avoid conversions from ```.get()``` to ```.contains()```
   for array types. Sigh. Shouldn't be working >12h a day and then do some more stuff at home.
+- Fixed a bug in AssertThatBinaryExpression inspection for ```assertThat(null != expression)``` and related
+  that would not correctly invert the condition on transformation.
 
 #### V1.5 (24-Sep-19)
 - Fix for AssertThatCollectionOrMap inspection sometimes causing an index out of bounds exception.

build.gradle

@@ -47,6 +47,8 @@ patchPluginXml {
     <ul>
       <li>Really fixed AssertThatGuavaOptional inspections to avoid conversions from .get() to .contains()
           for array types. Sigh. Shouldn't be working &gt;12h a day and then do some more stuff at home.
+      <li>Fixed a bug in AssertThatBinaryExpression inspection for assertThat(null != expression) and related
+          that would not correctly invert the condition on transformation.
     </ul>
   <p>Full changelog available at <a href="https://github.com/chrisly42/cajon-plugin#changelog">Github project site</a>.</p>
 """

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

@@ -38,7 +38,13 @@ class AssertThatBinaryExpressionInspection : AbstractAssertJInspection() {
 
                 if (isLeftNull && isRightNull) return
                 if (isLeftNull || isRightNull) {
-                    val replacementMethod = expectedResult.map(MethodNames.IS_NULL, MethodNames.IS_NOT_NULL)
+                    val expectedResultOnOp =
+                        when (binaryExpression.operationTokenType) {
+                            JavaTokenType.EQEQ -> expectedResult
+                            JavaTokenType.NE -> !expectedResult
+                            else -> return
+                        }
+                    val replacementMethod = expectedResultOnOp.map(MethodNames.IS_NULL, MethodNames.IS_NOT_NULL)
                     registerSplitMethod(holder, expectedCallExpression, replacementMethod) { desc, method ->
                         SplitBinaryExpressionMethodCallQuickFix(desc, method, pickRightOperand = isLeftNull, noExpectedExpression = true)
                     }

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

@@ -13,7 +13,7 @@ internal class AssertThatBinaryExpressionInspectionTest : AbstractCajonTest() {
     internal fun assertThat_of_binary_expression_can_be_moved_out(@MyFixture myFixture: JavaCodeInsightTestFixture) {
         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 binary expression out of assertThat()"), 161)
         myFixture.checkResultByFile("BinaryExpressionAfter.java")
     }
 }

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

@@ -189,6 +189,20 @@ public class BinaryExpression {
         assertThat(stringAct).isNotNull();
         assertThat(stringAct).isNotNull();
 
+        assertThat(stringAct).as("doh!").isNotNull();
+        assertThat(stringAct).isNotNull();
+        assertThat(stringAct).isNotNull();
+        assertThat(stringAct).isNull();
+        assertThat(stringAct).isNull();
+        assertThat(stringAct).isNull();
+
+        assertThat(stringAct).as("doh!").isNotNull();
+        assertThat(stringAct).isNotNull();
+        assertThat(stringAct).isNotNull();
+        assertThat(stringAct).isNull();
+        assertThat(stringAct).isNull();
+        assertThat(stringAct).isNull();
+
         assertThat(null == null).isTrue();
         assertThat(!false).isTrue();
 

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

@@ -189,6 +189,20 @@ public class BinaryExpression {
         assertThat(null == stringAct).isEqualTo(false);
         assertThat(null == stringAct).isNotEqualTo(true);
 
+        assertThat(stringAct != null).as("doh!").isTrue();
+        assertThat(stringAct != null).isEqualTo(true);
+        assertThat(stringAct != null).isNotEqualTo(false);
+        assertThat(stringAct != null).isFalse();
+        assertThat(stringAct != null).isEqualTo(false);
+        assertThat(stringAct != null).isNotEqualTo(true);
+
+        assertThat(null != stringAct).as("doh!").isTrue();
+        assertThat(null != stringAct).isEqualTo(true);
+        assertThat(null != stringAct).isNotEqualTo(false);
+        assertThat(null != stringAct).isFalse();
+        assertThat(null != stringAct).isEqualTo(false);
+        assertThat(null != stringAct).isNotEqualTo(true);
+
         assertThat(null == null).isTrue();
         assertThat(!false).isTrue();