Issue 26050. Don't suggest to import an already imported (with 'show') library again.

pkg/analysis_server/test/services/correction/fix_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.correction.fix;
 
 import 'dart:async';
 
 import 'package:analysis_server/plugin/edit/fix/fix_core.dart';
 import 'package:analysis_server/plugin/edit/fix/fix_dart.dart';
@@ skipping 3442 matching lines @@
         DartFixKind.IMPORT_LIBRARY_SDK,
         '''
 import 'dart:math';
 
 @PI
 main() {
 }
 ''');
   }
 
-  test_importLibraryShow() async {
+  test_importLibraryShow_project() async {
+    testFile = '/project/bin/test.dart';
+    addSource(
+        '/project/bin/lib.dart',
+        '''
+class A {}
+class B {}
+''');
+    resolveTestUnit('''
+import 'lib.dart' show A;
+main() {
+  A a;
+  B b;
+}
+''');
+    performAllAnalysisTasks();
+    await assertNoFix(DartFixKind.IMPORT_LIBRARY_PROJECT);
+    await assertHasFix(
+        DartFixKind.IMPORT_LIBRARY_SHOW,
+        '''
+import 'lib.dart' show A, B;
+main() {
+  A a;
+  B b;
+}
+''');
+  }
+
+  test_importLibraryShow_sdk() async {
     resolveTestUnit('''
 import 'dart:async' show Stream;
 main() {
   Stream s = null;
   Future f = null;
 }
 ''');
+    await assertNoFix(DartFixKind.IMPORT_LIBRARY_SDK);
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_SHOW,
         '''
 import 'dart:async' show Future, Stream;
 main() {
   Stream s = null;
   Future f = null;
 }
 ''');
   }
@@ skipping 1803 matching lines @@
   @override
   void t() { }
 }
 ''');
   }
 
   void verifyResult(String expectedResult) {
     expect(resultCode, expectedResult);
   }
 }