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

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

@@ -30,6 +30,13 @@ public class Java8Optional {
         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";