blob: 00e5a81aa479b23982a395aa077f4250f1d4f26e [file] [log] [blame]
// Copyright (c) 2016, 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 '../analyzer.dart';
import '../util/dart_type_utilities.dart';
import '../util/unrelated_types_visitor.dart';
const _desc = r'Invocation of `remove` with references of unrelated types.';
const _details = r'''
**DON'T** invoke `remove` on `List` with an instance of different type than
the parameter type.
Doing this will invoke `==` on its elements and most likely will
return `false`.
**BAD:**
```dart
void someFunction() {
var list = <int>[];
if (list.remove('1')) print('someFunction'); // LINT
}
```
**BAD:**
```dart
void someFunction3() {
List<int> list = <int>[];
if (list.remove('1')) print('someFunction3'); // LINT
}
```
**BAD:**
```dart
void someFunction8() {
List<DerivedClass2> list = <DerivedClass2>[];
DerivedClass3 instance;
if (list.remove(instance)) print('someFunction8'); // LINT
}
```
**BAD:**
```dart
abstract class SomeList<E> implements List<E> {}
abstract class MyClass implements SomeList<int> {
bool badMethod(String thing) => this.remove(thing); // LINT
}
```
**GOOD:**
```dart
void someFunction10() {
var list = [];
if (list.remove(1)) print('someFunction10'); // OK
}
```
**GOOD:**
```dart
void someFunction1() {
var list = <int>[];
if (list.remove(1)) print('someFunction1'); // OK
}
```
**GOOD:**
```dart
void someFunction4() {
List<int> list = <int>[];
if (list.remove(1)) print('someFunction4'); // OK
}
```
**GOOD:**
```dart
void someFunction5() {
List<ClassBase> list = <ClassBase>[];
DerivedClass1 instance;
if (list.remove(instance)) print('someFunction5'); // OK
}
abstract class ClassBase {}
class DerivedClass1 extends ClassBase {}
```
**GOOD:**
```dart
void someFunction6() {
List<Mixin> list = <Mixin>[];
DerivedClass2 instance;
if (list.remove(instance)) print('someFunction6'); // OK
}
abstract class ClassBase {}
abstract class Mixin {}
class DerivedClass2 extends ClassBase with Mixin {}
```
**GOOD:**
```dart
void someFunction7() {
List<Mixin> list = <Mixin>[];
DerivedClass3 instance;
if (list.remove(instance)) print('someFunction7'); // OK
}
abstract class ClassBase {}
abstract class Mixin {}
class DerivedClass3 extends ClassBase implements Mixin {}
```
''';
class ListRemoveUnrelatedType extends LintRule implements NodeLintRule {
ListRemoveUnrelatedType()
: super(
name: 'list_remove_unrelated_type',
description: _desc,
details: _details,
group: Group.errors);
@override
void registerNodeProcessors(
NodeLintRegistry registry, LinterContext context) {
var visitor = _Visitor(this, context.typeSystem);
registry.addMethodInvocation(this, visitor);
}
}
class _Visitor extends UnrelatedTypesProcessors {
static final _definition = InterfaceTypeDefinition('List', 'dart.core');
_Visitor(LintRule rule, TypeSystem typeSystem) : super(rule, typeSystem);
@override
InterfaceTypeDefinition get definition => _definition;
@override
String get methodName => 'remove';
}