| // Copyright (c) 2015, 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'Avoid empty else statements.'; |
| |
| const _details = r''' |
| |
| **AVOID** empty else statements. |
| |
| **BAD:** |
| ``` |
| if (x > y) |
| print("1"); |
| else ; |
| print("2"); |
| ``` |
| |
| '''; |
| |
| class AvoidEmptyElse extends LintRule implements NodeLintRule { |
| AvoidEmptyElse() |
| : super( |
| name: 'avoid_empty_else', |
| description: _desc, |
| details: _details, |
| group: Group.errors); |
| |
| @override |
| void registerNodeProcessors( |
| NodeLintRegistry registry, LinterContext context) { |
| final visitor = _Visitor(this); |
| registry.addIfStatement(this, visitor); |
| } |
| } |
| |
| class _Visitor extends SimpleAstVisitor<void> { |
| final LintRule rule; |
| |
| _Visitor(this.rule); |
| |
| @override |
| void visitIfStatement(IfStatement node) { |
| final elseStatement = node.elseStatement; |
| if (elseStatement is EmptyStatement && |
| !elseStatement.semicolon.isSynthetic) { |
| rule.reportLint(elseStatement); |
| } |
| } |
| } |