Issue 23389. Report error in the renamed element be invisible after rename.

pkg/analysis_server/test/services/refactoring/rename_class_member_test.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library test.services.refactoring.rename_class_member;
 
 import 'package:analysis_server/src/protocol.dart';
 import 'package:analysis_server/src/services/correction/status.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 import 'package:unittest/unittest.dart';
@@ skipping 37 matching lines @@
   }
 }
 ''');
     createRenameRefactoringAtString('test() {}');
     // check status
     refactoring.newName = 'newName';
     RefactoringStatus status = await refactoring.checkFinalConditions();
     assertRefactoringStatusOK(status);
   }
 
+  test_checkFinalConditions_publicToPrivate_usedInOtherLibrary() async {
+    indexTestUnit('''
+class A {
+  test() {}
+}
+''');
+    indexUnit('/lib.dart', '''
+library my.lib;
+import 'test.dart';
+
+main(A a) {
+  a.test();
+}
+''');
+    createRenameRefactoringAtString('test() {}');
+    // check status
+    refactoring.newName = '_newName';
+    RefactoringStatus status = await refactoring.checkFinalConditions();
+    assertRefactoringStatus(status, RefactoringProblemSeverity.ERROR,
+        expectedMessage: "Renamed method will be invisible in 'my.lib'.");
+  }
+
   test_checkFinalConditions_shadowed_byLocal_inSameClass() async {
     indexTestUnit('''
 class A {
   test() {}
   main() {
     var newName;
     test(); // marker
   }
 }
 ''');
@@ skipping 629 matching lines @@
     // validate change
     return assertSuccessfulRefactoring('''
 class A<NewName> {
   NewName field;
   List<NewName> items;
   NewName method(NewName p) => null;
 }
 ''');
   }
 }