| // Copyright (c) 2017, 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/token.dart'; |
| import 'package:analyzer/dart/ast/visitor.dart'; |
| import 'package:analyzer/dart/element/element.dart'; |
| |
| import '../analyzer.dart'; |
| import '../util/dart_type_utilities.dart'; |
| |
| const _desc = |
| r'Use a setter for operations that conceptually change a property.'; |
| |
| const _details = r''' |
| |
| **DO** use a setter for operations that conceptually change a property. |
| |
| **BAD:** |
| ``` |
| rectangle.setWidth(3); |
| button.setVisible(false); |
| ``` |
| |
| **GOOD:** |
| ``` |
| rectangle.width = 3; |
| button.visible = false; |
| ``` |
| |
| '''; |
| |
| class UseSettersToChangeAProperty extends LintRule implements NodeLintRule { |
| UseSettersToChangeAProperty() |
| : super( |
| name: 'use_setters_to_change_properties', |
| description: _desc, |
| details: _details, |
| group: Group.style); |
| |
| @override |
| void registerNodeProcessors( |
| NodeLintRegistry registry, LinterContext context) { |
| final visitor = _Visitor(this); |
| registry.addMethodDeclaration(this, visitor); |
| } |
| } |
| |
| class _Visitor extends SimpleAstVisitor<void> { |
| final LintRule rule; |
| |
| _Visitor(this.rule); |
| |
| @override |
| void visitMethodDeclaration(MethodDeclaration node) { |
| if (node.isSetter || |
| node.isGetter || |
| DartTypeUtilities.overridesMethod(node) || |
| node.parameters?.parameters?.length != 1 || |
| node.returnType?.type?.isVoid != true) { |
| return; |
| } |
| void _visitExpression(Expression expression) { |
| if (expression is AssignmentExpression && |
| expression.operator.type == TokenType.EQ) { |
| final leftOperand = |
| DartTypeUtilities.getCanonicalElement(expression.writeElement); |
| final rightOperand = |
| DartTypeUtilities.getCanonicalElementFromIdentifier( |
| expression.rightHandSide); |
| final parameterElement = node.declaredElement.parameters.first; |
| if (rightOperand == parameterElement && leftOperand is FieldElement) { |
| rule.reportLint(node); |
| } |
| } |
| } |
| |
| final body = node.body; |
| if (body is BlockFunctionBody) { |
| if (body.block.statements.length == 1) { |
| final statement = body.block.statements.first; |
| if (statement is ExpressionStatement) { |
| _visitExpression(statement.expression); |
| } |
| } |
| } else if (body is ExpressionFunctionBody) { |
| _visitExpression(body.expression); |
| } |
| } |
| } |