| // Copyright (c) 2021, 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. |
| |
| import 'package:analysis_server/src/services/completion/dart/completion_manager.dart'; |
| import 'package:analyzer/dart/analysis/features.dart'; |
| import 'package:analyzer/dart/element/element.dart'; |
| import 'package:analyzer/dart/element/nullability_suffix.dart'; |
| import 'package:analyzer/dart/element/type.dart'; |
| |
| extension DartCompletionRequestExtensions on DartCompletionRequest { |
| /// Return `true` if the constructor tear-offs feature is enabled, and the |
| /// context type is a function type that matches an instantiation of the |
| /// [element]. |
| /// |
| /// TODO(scheglov) Validate that suggesting a tear-off instead of invocation |
| /// is statistically a good choice. |
| bool shouldSuggestTearOff(ClassElement element) { |
| if (!libraryElement.featureSet.isEnabled(Feature.constructor_tearoffs)) { |
| return false; |
| } |
| |
| final contextType = this.contextType; |
| if (contextType is! FunctionType) { |
| return false; |
| } |
| |
| var bottomInstance = element.instantiate( |
| typeArguments: List.filled( |
| element.typeParameters.length, |
| libraryElement.typeProvider.neverType, |
| ), |
| nullabilitySuffix: NullabilitySuffix.none, |
| ); |
| |
| return libraryElement.typeSystem.isSubtypeOf( |
| bottomInstance, |
| contextType.returnType, |
| ); |
| } |
| } |