QuickFix. Issue 55804. Don't suggest creating mixin when it is a name…

… of property.

Bug: #55804
Change-Id: Ibbdeac3a662ef140fb88e834416f064c899365bf
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/368681
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Commit-Queue: Konstantin Shcheglov <scheglov@google.com>

pkg/analysis_server/lib/src/services/correction/dart/create_mixin.dart

@@ -40,14 +40,17 @@ class CreateMixin extends ResolvedCorrectionProducer {
       _mixinName = node.name2.lexeme;
     } else if (node is SimpleIdentifier) {
       var parent = node.parent;
-      var grandParent = parent?.parent;
-      if (parent is NamedType &&
-          grandParent is ConstructorName &&
-          grandParent.parent is InstanceCreationExpression) {
-        return;
-      } else {
-        _mixinName = node.name;
+      switch (parent) {
+        case PrefixedIdentifier():
+          if (parent.identifier == node) {
+            return;
+          }
+        case PropertyAccess():
+          if (parent.propertyName == node) {
+            return;
+          }
       }
+      _mixinName = node.name;
     } else if (node is PrefixedIdentifier) {
       if (node.parent is InstanceCreationExpression) {
         return;

pkg/analysis_server/test/src/services/correction/fix/create_mixin_test.dart

@@ -139,6 +139,45 @@ mixin Test {
     assertLinkedGroup(change.linkedEditGroups[0], ['Test])', 'Test {']);
   }
 
+  Future<void> test_prefixedIdentifier_identifier() async {
+    await resolveTestCode('''
+void f(C c) {
+  c.test;
+}
+
+class C {}
+''');
+    await assertNoFix();
+  }
+
+  Future<void> test_prefixedIdentifier_prefix() async {
+    await resolveTestCode('''
+void f() {
+  Test.value;
+}
+''');
+    await assertHasFix('''
+void f() {
+  Test.value;
+}
+
+mixin Test {
+}
+''');
+    assertLinkedGroup(change.linkedEditGroups[0], ['Test.value', 'Test {']);
+  }
+
+  Future<void> test_propertyAccess_property() async {
+    await resolveTestCode('''
+void f(C c) {
+  (c).test;
+}
+
+class C {}
+''');
+    await assertNoFix();
+  }
+
   Future<void> test_simple() async {
     await resolveTestCode('''
 void f() {