NPE (IDEA-176934)

java/java-impl/src/com/intellij/codeInsight/intention/impl/MoveInitializerToConstructorAction.java

@@ -57,7 +57,8 @@ public class MoveInitializerToConstructorAction extends BaseMoveInitializerToMet
         PsiClassInitializer[] initializers = containingClass.getInitializers();
         PsiElement[] elements = 
           Arrays.stream(containingClass.getFields())
-          .filter(f -> f.hasInitializer()).map(f -> f.getInitializer())
+          .map(f -> f.getInitializer())
+          .filter(Objects::nonNull)
           .toArray(PsiElement[]::new);
         return ReferencesSearch.search(field, new LocalSearchScope(ArrayUtil.mergeArrays(elements, initializers))).findFirst() == null;
       }

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/moveInitializerToConstructor/afterImplicitEnum.java

@@ -0,0 +1,9 @@
+// "Move initializer to constructor" "true"
+enum C {
+  foo;
+  private final String myExtension;
+
+  C() {
+      myExtension = null;
+  }
+}

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/moveInitializerToConstructor/beforeImplicitEnum.java

@@ -0,0 +1,8 @@
+// "Move initializer to constructor" "true"
+enum C {
+  foo;
+  private final String myExtension = n<caret>ull;
+
+  C() {
+  }
+}