check overriding in correct order (IDEA-97506)

java/java-psi-impl/src/com/intellij/psi/impl/PsiSuperMethodImplUtil.java

@@ -215,15 +215,15 @@ public class PsiSuperMethodImplUtil {
       LOG.assertTrue(copy.getMethod().isValid());
       map.put(signature, copy);
     }
+    else if (isSuperMethod(aClass, existing, hierarchicalMethodSignature)) {
+      mergeSupers(existing, hierarchicalMethodSignature);
+    }
     else if (isReturnTypeIsMoreSpecificThan(hierarchicalMethodSignature, existing) && isSuperMethod(aClass, hierarchicalMethodSignature, existing)) {
       HierarchicalMethodSignatureImpl newSuper = copy(hierarchicalMethodSignature);
       mergeSupers(newSuper, existing);
       LOG.assertTrue(newSuper.getMethod().isValid());
       map.put(signature, newSuper);
     }
-    else if (isSuperMethod(aClass, existing, hierarchicalMethodSignature)) {
-      mergeSupers(existing, hierarchicalMethodSignature);
-    }
     // just drop an invalid method declaration there - to highlight accordingly
     else if (!result.containsKey(signature)) {
       LOG.assertTrue(hierarchicalMethodSignature.getMethod().isValid());

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/genericsHighlighting/OverrideWithMoreSpecificReturn.java

@@ -0,0 +1,15 @@
+import java.util.List;
+
+interface ExampleInterface {
+    public List exampleMethod();
+}
+
+class ExampleSuperClass {
+    public List<String> exampleMethod() {
+        return null;
+    }
+}
+
+
+public class  ExampleSubClass extends ExampleSuperClass implements ExampleInterface {
+}

java/java-tests/testSrc/com/intellij/codeInsight/daemon/GenericsHighlightingTest.java

@@ -206,6 +206,7 @@ public class GenericsHighlightingTest extends LightDaemonAnalyzerTestCase {
   public void testFlattenIntersectionType() throws Exception { doTest17Incompatibility(false); }
   public void testIDEA97276() throws Exception { doTest17Incompatibility(false); }
   public void testWildcardsBoundsIntersection() throws Exception { doTest17Incompatibility(false); }
+  public void testOverrideWithMoreSpecificReturn() throws Exception { doTest17Incompatibility(false); }
 
   public void testJavaUtilCollections_NoVerify() throws Exception {
     PsiClass collectionsClass = getJavaFacade().findClass("java.util.Collections", GlobalSearchScope.moduleWithLibrariesScope(getModule()));