redundant cast: check binary comparison assignability (IDEA-209944)

GitOrigin-RevId: 4276128fb33224de60afc7661e478ca172205f51

java/java-analysis-impl/src/com/intellij/psi/util/RedundantCastUtil.java

@@ -697,6 +697,14 @@ public class RedundantCastUtil {
             addToResults(typeCast);
           }
         }
+        else if (parent instanceof PsiBinaryExpression) {
+          PsiExpression lOperand = ((PsiBinaryExpression)parent).getLOperand();
+          PsiExpression rOperand = ((PsiBinaryExpression)parent).getROperand();
+          PsiType oppositeType = lOperand == typeCast ? rOperand != null ? rOperand.getType() : null : lOperand.getType();
+          if (oppositeType != null && TypeConversionUtil.areTypesConvertible(opType, oppositeType)) {
+            addToResults(typeCast);
+          }
+        }
         else if (TypeConversionUtil.isAssignable(castTo, opType, false) &&
                  (expectedTypeByParent == null || TypeConversionUtil.isAssignable(expectedTypeByParent, opType, false))) {
           addToResults(typeCast);

java/java-tests/testData/inspection/redundantCast/generics/BinaryComparison.java

@@ -0,0 +1,9 @@
+class MyClass {
+    public <O> Class<O> getValueClass() {
+        return null;
+    }
+
+    public boolean isBooleanClass() {
+        return   (Class<?>) getValueClass() == Boolean.class;
+    }
+}

java/java-tests/testSrc/com/intellij/java/codeInspection/RedundantCast15Test.java

@@ -55,6 +55,7 @@ public class RedundantCast15Test extends LightCodeInsightFixtureTestCase {
   public void testForEachValueIDEA126166() { doTest();}
   public void testCaseThrowable() { doTest();}
   public void testSafeTempVarName() { doTest();}
+  public void testBinaryComparison() { doTest();}
 
   public void testTypeParameterAccessChecksJava7() {
     doTest();