Issue 25542. If an element does not have its own documentation, use the documentation from the over…

pkg/analysis_server/test/analysis/get_hover_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.domain.analysis.hover;
 
 import 'dart:async';
 
 import 'package:analysis_server/plugin/protocol/protocol.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
@@ skipping 78 matching lines @@
 library my.library;
 /// doc aaa
 /// doc bbb
 main() {
 }
 ''');
     HoverInformation hover = await prepareHover('main() {');
     expect(hover.dartdoc, '''doc aaa\ndoc bbb''');
   }
 
+  test_dartdoc_inherited_methodByMethod_fromInterface() async {
+    addTestFile('''
+class A {
+  /// my doc
+  m() {} // in A
+}
+
+class B implements A {
+  m() {} // in B
+}
+''');
+    HoverInformation hover = await prepareHover('m() {} // in B');
+    expect(hover.dartdoc, '''my doc\n\nCopied from `A`.''');
+  }
+
+  test_dartdoc_inherited_methodByMethod_fromSuper_direct() async {
+    addTestFile('''
+class A {
+  /// my doc
+  m() {} // in A
+}
+
+class B extends A {
+  m() {} // in B
+}
+''');
+    HoverInformation hover = await prepareHover('m() {} // in B');
+    expect(hover.dartdoc, '''my doc\n\nCopied from `A`.''');
+  }
+
+  test_dartdoc_inherited_methodByMethod_fromSuper_indirect() async {
+    addTestFile('''
+class A {
+  /// my doc
+  m() {}
+}
+class B extends A {
+  m() {}
+}
+class C extends B {
+  m() {} // in C
+}''');
+    HoverInformation hover = await prepareHover('m() {} // in C');
+    expect(hover.dartdoc, '''my doc\n\nCopied from `A`.''');
+  }
+
+  test_dartdoc_inherited_methodByMethod_preferSuper() async {
+    addTestFile('''
+class A {
+  /// my doc
+  m() {}
+}
+class B extends A {
+}
+class I {
+  // wrong doc
+  m() {}
+}
+class C extends B implements I {
+  m() {} // in C
+}''');
+    HoverInformation hover = await prepareHover('m() {} // in C');
+    expect(hover.dartdoc, '''my doc\n\nCopied from `A`.''');
+  }
+
   test_enum() async {
     addTestFile('''
 enum MyEnum {AAA, BBB, CCC}
 ''');
     HoverInformation hover = await prepareHover('MyEnum');
     expect(hover.elementDescription, 'enum MyEnum');
     expect(hover.staticType, isNull);
     expect(hover.propagatedType, isNull);
   }
 
@@ skipping 285 matching lines @@
     addTestFile('''
 library my.library;
 main() {
   // nothing
 }
 ''');
     HoverInformation hover = await prepareHover('nothing');
     expect(hover, isNull);
   }
 }