Calculate default args for local reference completions.

pkg/analysis_server/test/services/completion/dart/local_reference_contributor_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.completion.contributor.dart.local_ref;
 
 import 'package:analysis_server/plugin/protocol/protocol.dart' as protocol
     show Element, ElementKind;
 import 'package:analysis_server/plugin/protocol/protocol.dart'
     hide Element, ElementKind;
@@ skipping 4579 matching lines @@
     assertNotSuggested('x');
     assertNotSuggested('e');
   }
 }
 
 @reflectiveTest
 class LocalReferenceContributorTest_Driver
     extends LocalReferenceContributorTest {
   @override
   bool get enableNewAnalysisDriver => true;
+
+  test_ArgDefaults_function() async {
+    addTestSource('''
+bool hasLength(int expected, bool b) => false;
+void main() {h^}''');
+    await computeSuggestions();
+
+    assertSuggestFunction('hasLength', 'bool',
+        relevance: DART_RELEVANCE_LOCAL_FUNCTION,
+        defaultArgListString: 'expected, b');
+  }
+
+  test_ArgDefaults_function_none() async {
+    addTestSource('''
+bool hasLength() => false;
+void main() {h^}''');
+    await computeSuggestions();
+
+    assertSuggestFunction('hasLength', 'bool',
+        relevance: DART_RELEVANCE_LOCAL_FUNCTION, defaultArgListString: null);
+  }
+
+  test_ArgDefaults_function_with_optional_positional() async {
+    _addMetaPackageSource();
+    addTestSource('''
+import 'package:meta/meta.dart';
+
+bool foo(int bar, [bool boo, int baz]) => false;
+void main() {h^}''');
+    await computeSuggestions();
+
+    assertSuggestFunction('foo', 'bool',
+        relevance: DART_RELEVANCE_LOCAL_FUNCTION, defaultArgListString: 'bar');
+  }
+
+  test_ArgDefaults_function_with_required_named() async {
+    _addMetaPackageSource();
+    addTestSource('''
+import 'package:meta/meta.dart';
+
+bool foo(int bar, {bool boo, @required int baz}) => false;
+void main() {h^}''');
+    await computeSuggestions();
+
+    assertSuggestFunction('foo', 'bool',
+        relevance: DART_RELEVANCE_LOCAL_FUNCTION,
+        defaultArgListString: 'bar, baz: null');
+  }
+
+  void _addMetaPackageSource() {
+    addPackageSource(
+        'meta',
+        'meta.dart',
+        r'''
+library meta;
+
+const Required required = const Required();
+
+class Required {
+  final String reason;
+  const Required([this.reason]);
 }
+''');
+  }
+}