pkg/linter/lib/src/rules/empty_constructor_bodies.dart

// 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'Use `;` instead of `{}` for empty constructor bodies.';

class EmptyConstructorBodies extends LintRule {
  EmptyConstructorBodies()
      : super(
          name: LintNames.empty_constructor_bodies,
          description: _desc,
        );

  @override
  LintCode get lintCode => LinterLintCode.empty_constructor_bodies;

  @override
  void registerNodeProcessors(
      NodeLintRegistry registry, LinterContext context) {
    var visitor = _Visitor(this);
    registry.addConstructorDeclaration(this, visitor);
  }
}

class _Visitor extends SimpleAstVisitor<void> {
  final LintRule rule;

  _Visitor(this.rule);

  @override
  void visitConstructorDeclaration(ConstructorDeclaration node) {
    var body = node.body;
    if (body is BlockFunctionBody) {
      var block = body.block;
      if (block.statements.isEmpty) {
        if (block.endToken.precedingComments == null) {
          rule.reportLint(block);
        }
      }
    }
  }
}