pkg/linter/test/rules/hash_and_equals_test.dart

// Copyright (c) 2022, 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:test_reflective_loader/test_reflective_loader.dart';

import '../rule_test_support.dart';

void main() {
  defineReflectiveSuite(() {
    defineReflectiveTests(HashAndEqualsTest);
  });
}

@reflectiveTest
class HashAndEqualsTest extends LintRuleTest {
  @override
  String get lintRule => LintNames.hash_and_equals;

  test_augmentedClass_augmentation() async {
    newFile('$testPackageLibPath/a.dart', r'''
part 'test.dart';

class A {
  int get hashCode => 0;
}
''');

    await assertNoDiagnostics(r'''
part of 'a.dart';

augment class A {
  bool operator ==(Object other) => false;
}
''');
  }

  test_augmentedClass_augmentation_missingHash() async {
    newFile('$testPackageLibPath/a.dart', r'''
part 'test.dart';

class A { }
''');

    await assertDiagnostics(
      r'''
part of 'a.dart';

augment class A {
  bool operator ==(Object other) => false;
}
''',
      [lint(53, 2)],
    );
  }

  test_enum_missingHash() async {
    await assertDiagnostics(
      r'''
enum A {
  a,b,c;
  @override
  bool operator ==(Object other) => false;
}
''',
      [
        error(CompileTimeErrorCode.illegalConcreteEnumMemberDeclaration, 46, 2),
        // no lint
      ],
    );
  }

  test_equalsEquals_andHashCode() async {
    await assertNoDiagnostics(r'''
class C {
  @override
  bool operator ==(Object other) => false;

  @override
  int get hashCode => 7;
}
''');
  }

  test_equalsEquals_andHashCodeField() async {
    await assertNoDiagnostics(r'''
class C {
  @override
  bool operator ==(Object other) => false;

  @override
  int hashCode = 7;
}
''');
  }

  test_equalsEquals_noHashCode() async {
    await assertDiagnostics(
      r'''
class C {
  @override
  bool operator ==(Object other) => false;
}
''',
      [lint(38, 2)],
    );
  }

  test_extensionType_missingHash() async {
    await assertDiagnostics(
      r'''
extension type E(Object o) {
  bool operator ==(Object other) => false;
}
''',
      [
        // No lint.
        error(CompileTimeErrorCode.extensionTypeDeclaresMemberOfObject, 45, 2),
      ],
    );
  }

  test_hashCode_noEqualsEquals() async {
    await assertDiagnostics(
      r'''
class C {
  @override
  int get hashCode => 7;
}
''',
      [lint(32, 8)],
    );
  }

  test_hashCodeField_missingEqualsEquals() async {
    await assertDiagnostics(
      r'''
class C {
  @override
  final int hashCode = 7;
}
''',
      [lint(34, 8)],
    );
  }

  test_neither() async {
    await assertNoDiagnostics(r'''
class C {}
''');
  }
}