test/rules/null_closures.dart

// Copyright (c) 2021, 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';

main() {
  defineReflectiveSuite(() {
    defineReflectiveTests(NullClosuresPreNNBDTest);
    defineReflectiveTests(NullClosuresTest);
  });
}

@reflectiveTest
class NullClosuresPreNNBDTest extends LintRuleTest {
  @override
  String get lintRule => 'null_closures';

  test_list_firstWhere() async {
    await assertNoDiagnostics(r'''
// @dart=2.9

f() => <int>[2, 4, 6].firstWhere((e) => e.isEven, orElse: () => null);
''');
  }

  test_list_generate() async {
    await assertDiagnostics(r'''
// @dart=2.9

f() => List.generate(3, null);
''', [
      lint('null_closures', 38, 4),
    ]);
  }

  test_list_where() async {
    await assertDiagnostics(r'''
// @dart=2.9

f() => <int>[2, 4, 6].where(null);
''', [
      lint('null_closures', 42, 4),
    ]);
  }

  test_map_putIfAbsent() async {
    await assertDiagnostics(r'''
// @dart=2.9

f() {
  var map = <int, int>{};
  map.putIfAbsent(7, null);
  return map;
}
''', [
      lint('null_closures', 67, 4),
    ]);
  }
}

@reflectiveTest
class NullClosuresTest extends LintRuleTest {
  @override
  String get lintRule => 'null_closures';

  ///https://github.com/dart-lang/linter/issues/1414
  test_recursiveInterfaceInheritance() async {
    await assertDiagnostics(r'''
class A extends B {
  A(int x);
}

class B extends A {}

void test_cycle() {
  A(null);
}
''', [
      // No lint
      error(CompileTimeErrorCode.RECURSIVE_INTERFACE_INHERITANCE, 6, 1),
      error(CompileTimeErrorCode.RECURSIVE_INTERFACE_INHERITANCE, 41, 1),
      error(CompileTimeErrorCode.NO_DEFAULT_SUPER_CONSTRUCTOR_IMPLICIT, 41, 1),
      error(CompileTimeErrorCode.ARGUMENT_TYPE_NOT_ASSIGNABLE, 81, 4),
    ]);
  }
}