Add defaultCompletionSorter allowing sorting to be overridden - fixes #24339

pkg/analysis_server/test/domain_completion_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.completion;
 
 import 'dart:async';
 
 import 'package:analysis_server/completion/completion_core.dart'
     show CompletionRequest, CompletionResult;
 import 'package:analysis_server/src/analysis_server.dart';
 import 'package:analysis_server/src/channel/channel.dart';
 import 'package:analysis_server/src/constants.dart';
 import 'package:analysis_server/src/context_manager.dart';
 import 'package:analysis_server/src/domain_analysis.dart';
 import 'package:analysis_server/src/domain_completion.dart';
 import 'package:analysis_server/src/plugin/server_plugin.dart';
 import 'package:analysis_server/src/protocol.dart';
 import 'package:analysis_server/src/services/completion/completion_manager.dart';
+import 'package:analysis_server/src/services/completion/contribution_sorter.dart';
 import 'package:analysis_server/src/services/completion/dart_completion_manager.dart';
 import 'package:analysis_server/src/services/index/index.dart' show Index;
 import 'package:analysis_server/src/services/index/local_memory_index.dart';
 import 'package:analysis_server/src/services/search/search_engine.dart';
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/instrumentation/instrumentation.dart';
 import 'package:analyzer/source/pub_package_map_provider.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/sdk.dart';
 import 'package:analyzer/src/generated/source.dart';
@@ skipping 433 matching lines @@
 
   test_invocation() {
     addTestFile('class A {b() {}} main() {A a; a.^}');
     return getSuggestions().then((_) {
       expect(replacementOffset, equals(completionOffset));
       expect(replacementLength, equals(0));
       assertHasResult(CompletionSuggestionKind.INVOCATION, 'b');
     });
   }
 
+  test_invocation_sdk_relevancy_off() {
+    var originalSorter = DartCompletionManager.defaultContributionSorter;
+    var mockSorter = new MockRelevancySorter();
+    DartCompletionManager.defaultContributionSorter = mockSorter;
+    addTestFile('main() {Map m; m.^}');
+    return getSuggestions().then((_) {
+      // Assert that the CommonUsageComputer has been replaced
+      expect(suggestions.any((s) => s.relevance == DART_RELEVANCE_COMMON_USAGE),
+          isFalse);
+      DartCompletionManager.defaultContributionSorter = originalSorter;
+      expect(mockSorter.count, 2);
+    });
+  }
+
+  test_invocation_sdk_relevancy_on() {
+    addTestFile('main() {Map m; m.^}');
+    return getSuggestions().then((_) {
+      // Assert that the CommonUsageComputer is working
+      expect(suggestions.any((s) => s.relevance == DART_RELEVANCE_COMMON_USAGE),
+          isTrue);
+    });
+  }
+
   test_invocation_withTrailingStmt() {
     addTestFile('class A {b() {}} main() {A a; a.^ int x = 7;}');
     return getSuggestions().then((_) {
       expect(replacementOffset, equals(completionOffset));
       expect(replacementLength, equals(0));
       assertHasResult(CompletionSuggestionKind.INVOCATION, 'b');
     });
   }
 
   test_keyword() {
@@ skipping 200 matching lines @@
   }
 
   @override
   TimestampedData<String> getContents(Source source) {
     return source.contents;
   }
 
   noSuchMethod(Invocation invocation) => super.noSuchMethod(invocation);
 }
 
+class MockRelevancySorter implements ContributionSorter {
+  int count = 0;
+
+  @override
+  void sort(DartCompletionRequest request) {
+    if (++count > 2) {
+      throw 'unexpected sort';
+    }
+  }
+}
+
 /**
  * Mock stream for tracking calls to listen and subscription.cancel.
  */
 class MockStream<E> implements Stream<E> {
   MockSubscription<E> mockSubscription = new MockSubscription<E>();
   int listenCount = 0;
 
   int get cancelCount => mockSubscription.cancelCount;
 
   @override
@@ skipping 98 matching lines @@
 }
     ''');
     await waitForTasksFinished();
     Request request =
         new CompletionGetSuggestionsParams(testFile, 0).toRequest('0');
     Response response = handler.handleRequest(request);
     expect(response.error, isNotNull);
     expect(response.error.code, RequestErrorCode.NO_INDEX_GENERATED);
   }
 }