| // Copyright (c) 2018, 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:analyzer/dart/ast/ast.dart'; |
| import 'package:analyzer/dart/ast/visitor.dart'; |
| |
| import '../analyzer.dart'; |
| |
| const _desc = r'Prefer generic function type aliases.'; |
| |
| const _details = r''' |
| |
| **PREFER** generic function type aliases. |
| |
| With the introduction of generic functions, function type aliases |
| (`typedef void F()`) couldn't express all of the possible kinds of |
| parameterization that users might want to express. Generic function type aliases |
| (`typedef F = void Function()`) fixed that issue. |
| |
| For consistency and readability reasons, it's better to only use one syntax and |
| thus prefer generic function type aliases. |
| |
| **BAD:** |
| ``` |
| typedef void F(); |
| ``` |
| |
| **GOOD:** |
| ``` |
| typedef F = void Function(); |
| ``` |
| |
| '''; |
| |
| class PreferGenericFunctionTypeAliases extends LintRule |
| implements NodeLintRule { |
| PreferGenericFunctionTypeAliases() |
| : super( |
| name: 'prefer_generic_function_type_aliases', |
| description: _desc, |
| details: _details, |
| group: Group.style); |
| |
| @override |
| void registerNodeProcessors( |
| NodeLintRegistry registry, LinterContext context) { |
| final visitor = _Visitor(this); |
| registry.addFunctionTypeAlias(this, visitor); |
| } |
| } |
| |
| class _Visitor extends SimpleAstVisitor<void> { |
| final LintRule rule; |
| |
| _Visitor(this.rule); |
| |
| @override |
| void visitFunctionTypeAlias(FunctionTypeAlias node) { |
| rule.reportLint(node.name); |
| } |
| } |