enable create enum constant from switch label statements (IDEA-84054)

java/java-impl/src/com/intellij/codeInsight/daemon/impl/quickfix/CreateFromUsageBaseFix.java

@@ -287,6 +287,18 @@ public abstract class CreateFromUsageBaseFix extends BaseIntentionAction {
     }
     else if (element instanceof PsiReferenceExpression) {
       qualifier = ((PsiReferenceExpression)element).getQualifierExpression();
+      if (qualifier == null) {
+        final PsiElement parent = element.getParent();
+        if (parent instanceof PsiSwitchLabelStatement) {
+          final PsiSwitchStatement switchStatement = PsiTreeUtil.getParentOfType(parent, PsiSwitchStatement.class);
+          if (switchStatement != null) {
+            final PsiExpression expression = switchStatement.getExpression();
+            if (expression != null) {
+              psiClass = PsiUtil.resolveClassInClassTypeOnly(expression.getType());
+            }
+          }
+        }
+      }
     }
     else if (element instanceof PsiMethodCallExpression) {
       final PsiReferenceExpression methodExpression = ((PsiMethodCallExpression)element).getMethodExpression();

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/createEnumConstantFromUsage/afterSwitchLabel.java

@@ -0,0 +1,14 @@
+// "Create Enum Constant 'D3'" "true"
+public enum Demo {
+    D3
+}
+
+class Show {
+
+    public void doSomething(Demo d) {
+        switch (d) {
+          case D3:
+            break;
+        }
+    }
+}

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/createEnumConstantFromUsage/afterSwitchLabel1.java

@@ -0,0 +1,14 @@
+// "Create Enum Constant 'D3'" "true"
+public enum Demo {
+    D3
+}
+
+class Show {
+
+    public void doSomething(Demo d) {
+        switch (d) {
+          case Demo.D3:
+            break;
+        }
+    }
+}

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/createEnumConstantFromUsage/beforeSwitchLabel.java

@@ -0,0 +1,13 @@
+// "Create Enum Constant 'D3'" "true"
+public enum Demo {
+}
+
+class Show {
+
+    public void doSomething(Demo d) {
+        switch (d) {
+          case D<caret>3:
+            break;
+        }
+    }
+}

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/createEnumConstantFromUsage/beforeSwitchLabel1.java

@@ -0,0 +1,13 @@
+// "Create Enum Constant 'D3'" "true"
+public enum Demo {
+}
+
+class Show {
+
+    public void doSomething(Demo d) {
+        switch (d) {
+          case Demo.D<caret>3:
+            break;
+        }
+    }
+}