Add defaultCompletionSorter allowing sorting to be overridden - fixes #24339

pkg/analysis_server/test/domain_completion_test.dart

Index: pkg/analysis_server/test/domain_completion_test.dart
diff --git a/pkg/analysis_server/test/domain_completion_test.dart b/pkg/analysis_server/test/domain_completion_test.dart
index 3c3306e844c5594c8bf6a4f3773c64df6d9b4511..577363621551f3517254a65c74ce0b9fccfa285a 100644
--- a/pkg/analysis_server/test/domain_completion_test.dart
+++ b/pkg/analysis_server/test/domain_completion_test.dart
@@ -17,6 +17,7 @@ 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';
@@ -470,6 +471,29 @@ class CompletionTest extends AbstractAnalysisTest {
     });
   }
 
+  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((_) {
@@ -690,6 +714,17 @@ class MockContext implements AnalysisContext {
   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.
  */