enum constants should be checked to implement enum interfaces

java/java-psi-api/src/com/intellij/codeInsight/ClassUtil.java

@@ -45,7 +45,7 @@ public class ClassUtil {
   @Nullable
   public static PsiMethod getAnyMethodToImplement(@NotNull PsiClass aClass) {
     final PsiClass superClass = aClass instanceof PsiAnonymousClass ? PsiUtil.resolveClassInClassTypeOnly(((PsiAnonymousClass)aClass).getBaseClassType()) : aClass.getSuperClass();
-    if (superClass != null && !superClass.hasModifierProperty(PsiModifier.ABSTRACT) && aClass.getImplementsListTypes().length == 0) {
+    if (superClass != null && !superClass.hasModifierProperty(PsiModifier.ABSTRACT) && !superClass.isEnum() && aClass.getImplementsListTypes().length == 0) {
       return null;
     }
     Set<PsiMethod> alreadyImplemented = new THashSet<PsiMethod>();

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/advHighlighting6/EnumConstantWithoutInterfaceImplementation.java

@@ -0,0 +1,8 @@
+
+interface A {
+  void m();
+}
+
+enum E implements A {
+  <error descr="Class 'Anonymous class derived from E' must implement abstract method 'm()' in 'A'">F</error>() {};
+}

java/java-tests/testSrc/com/intellij/codeInsight/daemon/LightAdvHighlightingJdk6Test.java

@@ -78,4 +78,8 @@ public class LightAdvHighlightingJdk6Test extends LightDaemonAnalyzerTestCase {
   public void testThisInArgListOfAnonymous() {
     doTest(false, false);
   }
+
+  public void testEnumConstantWithoutInterfaceImplementation() throws Exception {
+    doTest(false, false);
+  }
 }