quick fix for unnecessary_constructor_name

Fixes: https://github.com/dart-lang/sdk/issues/47102

Change-Id: Idd8b44379d49f416eb4d671ed95ed5f9433af00c
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/212800
Commit-Queue: Phil Quitslund <pquitslund@google.com>
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>

pkg/analysis_server/lib/src/services/correction/dart/remove_constructor_name.dart

@@ -0,0 +1,39 @@
+// 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:analysis_server/src/services/correction/dart/abstract_producer.dart';
+import 'package:analysis_server/src/services/correction/fix.dart';
+import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer_plugin/utilities/change_builder/change_builder_core.dart';
+import 'package:analyzer_plugin/utilities/fixes/fixes.dart';
+import 'package:analyzer_plugin/utilities/range_factory.dart';
+
+class RemoveConstructorName extends CorrectionProducer {
+  @override
+  bool get canBeAppliedInBulk => true;
+
+  @override
+  bool get canBeAppliedToFile => true;
+
+  @override
+  FixKind get fixKind => DartFixKind.REMOVE_CONSTRUCTOR_NAME;
+
+  @override
+  FixKind get multiFixKind => DartFixKind.REMOVE_CONSTRUCTOR_NAME_MULTI;
+
+  @override
+  Future<void> compute(ChangeBuilder builder) async {
+    final identifier = node;
+    if (identifier is! SimpleIdentifier) return;
+
+    // The '.' in ".new"
+    var dotToken = identifier.token.previous!;
+    await builder.addDartFileEdit(file, (builder) {
+      builder.addDeletion(range.startStart(dotToken, identifier.token.next!));
+    });
+  }
+
+  /// Return an instance of this class. Used as a tear-off in `FixProcessor`.
+  static RemoveConstructorName newInstance() => RemoveConstructorName();
+}

pkg/analysis_server/lib/src/services/correction/fix.dart

@@ -755,6 +755,16 @@ class DartFixKind {
     DartFixKindPriority.DEFAULT,
     'Remove const',
   );
+  static const REMOVE_CONSTRUCTOR_NAME = FixKind(
+    'dart.fix.remove.constructorName',
+    DartFixKindPriority.DEFAULT,
+    "Remove 'new'",
+  );
+  static const REMOVE_CONSTRUCTOR_NAME_MULTI = FixKind(
+    'dart.fix.remove.constructorName.multi',
+    DartFixKindPriority.IN_FILE,
+    'Remove constructor names in file',
+  );
   static const REMOVE_DEAD_CODE = FixKind(
     'dart.fix.remove.deadCode',
     DartFixKindPriority.DEFAULT,

pkg/analysis_server/lib/src/services/correction/fix_internal.dart

@@ -97,6 +97,7 @@ import 'package:analysis_server/src/services/correction/dart/remove_argument.dar
 import 'package:analysis_server/src/services/correction/dart/remove_await.dart';
 import 'package:analysis_server/src/services/correction/dart/remove_comparison.dart';
 import 'package:analysis_server/src/services/correction/dart/remove_const.dart';
+import 'package:analysis_server/src/services/correction/dart/remove_constructor_name.dart';
 import 'package:analysis_server/src/services/correction/dart/remove_dead_code.dart';
 import 'package:analysis_server/src/services/correction/dart/remove_dead_if_null.dart';
 import 'package:analysis_server/src/services/correction/dart/remove_duplicate_case.dart';
@@ -557,6 +558,9 @@ class FixProcessor extends BaseProcessor {
     LintNames.unnecessary_const: [
       RemoveUnnecessaryConst.newInstance,
     ],
+    LintNames.unnecessary_constructor_name: [
+      RemoveConstructorName.newInstance,
+    ],
     LintNames.unnecessary_final: [
       ReplaceFinalWithVar.newInstance,
     ],

pkg/analysis_server/lib/src/services/linter/lint_names.dart

@@ -111,6 +111,8 @@ class LintNames {
   static const String unnecessary_brace_in_string_interps =
       'unnecessary_brace_in_string_interps';
   static const String unnecessary_const = 'unnecessary_const';
+  static const String unnecessary_constructor_name =
+      'unnecessary_constructor_name';
   static const String unnecessary_final = 'unnecessary_final';
   static const String unnecessary_lambdas = 'unnecessary_lambdas';
   static const String unnecessary_new = 'unnecessary_new';

pkg/analysis_server/test/src/services/correction/fix/remove_constructor_name_test.dart

@@ -0,0 +1,106 @@
+// 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:analysis_server/src/services/correction/fix.dart';
+import 'package:analysis_server/src/services/linter/lint_names.dart';
+import 'package:analyzer_plugin/utilities/fixes/fixes.dart';
+import 'package:test/expect.dart';
+import 'package:test_reflective_loader/test_reflective_loader.dart';
+
+import 'fix_processor.dart';
+
+void main() {
+  defineReflectiveSuite(() {
+    defineReflectiveTests(RemoveConstructorNameBulkTest);
+    defineReflectiveTests(RemoveConstructorNameInFileTest);
+    defineReflectiveTests(RemoveConstructorNameTest);
+  });
+}
+
+@reflectiveTest
+class RemoveConstructorNameBulkTest extends BulkFixProcessorTest {
+  @override
+  String get lintCode => LintNames.unnecessary_constructor_name;
+
+  Future<void> test_singleFile() async {
+    await resolveTestCode(r'''
+class A {
+  A.new(int x) {
+    print('new: $x');
+  }
+}
+var a = A.new(3);
+''');
+    await assertHasFix(r'''
+class A {
+  A(int x) {
+    print('new: $x');
+  }
+}
+var a = A(3);
+''');
+  }
+}
+
+@reflectiveTest
+class RemoveConstructorNameInFileTest extends FixInFileProcessorTest {
+  Future<void> test_File() async {
+    createAnalysisOptionsFile(lints: [LintNames.unnecessary_constructor_name]);
+    await resolveTestCode(r'''
+class A {
+  A.new(int x) {
+    print('new: $x');
+  }
+}
+var a = A.new(3);
+''');
+    var fixes = await getFixesForFirstError();
+    expect(fixes, hasLength(1));
+    assertProduces(fixes.first, r'''
+class A {
+  A(int x) {
+    print('new: $x');
+  }
+}
+var a = A(3);
+''');
+  }
+}
+
+@reflectiveTest
+class RemoveConstructorNameTest extends FixProcessorLintTest {
+  @override
+  FixKind get kind => DartFixKind.REMOVE_CONSTRUCTOR_NAME;
+
+  @override
+  String get lintCode => LintNames.unnecessary_constructor_name;
+
+  Future<void> test_constructorDeclaration() async {
+    await resolveTestCode(r'''
+class A {
+  A.new(int x) {
+    print('new: $x');
+  }
+}
+''');
+    await assertHasFix(r'''
+class A {
+  A(int x) {
+    print('new: $x');
+  }
+}
+''');
+  }
+
+  Future<void> test_constructorInvocation() async {
+    await resolveTestCode(r'''
+class A { }
+var a = A.new();
+''');
+    await assertHasFix(r'''
+class A { }
+var a = A();
+''');
+  }
+}

pkg/analysis_server/test/src/services/correction/fix/test_all.dart

@@ -117,6 +117,7 @@ import 'remove_argument_test.dart' as remove_argument;
 import 'remove_await_test.dart' as remove_await;
 import 'remove_comparison_test.dart' as remove_comparison;
 import 'remove_const_test.dart' as remove_const;
+import 'remove_constructor_name_test.dart' as remove_constructor_name;
 import 'remove_dead_code_test.dart' as remove_dead_code;
 import 'remove_duplicate_case_test.dart' as remove_duplicate_case;
 import 'remove_empty_catch_test.dart' as remove_empty_catch;
@@ -300,6 +301,7 @@ void main() {
     remove_await.main();
     remove_comparison.main();
     remove_const.main();
+    remove_constructor_name.main();
     remove_dead_code.main();
     remove_duplicate_case.main();
     remove_empty_catch.main();