quick-fix to wrap in unawaited

Fixes: https://github.com/dart-lang/sdk/issues/49262

See also: https://github.com/dart-lang/linter/issues/3429

Change-Id: I0d3bf6c72ae1cf3e08f50b4deda10aba52e25eb4
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/248480
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Commit-Queue: Phil Quitslund <pquitslund@google.com>

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

@@ -0,0 +1,42 @@
+// 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: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 WrapInUnawaited extends CorrectionProducer {
+  @override
+  FixKind get fixKind => DartFixKind.WRAP_IN_UNAWAITED;
+
+  @override
+  Future<void> compute(ChangeBuilder builder) async {
+    AstNode? node = this.node;
+    if (node is SimpleIdentifier) {
+      node = node.parent;
+    }
+    Expression? expression;
+    if (node is Expression) {
+      expression = node;
+    } else if (node is ExpressionStatement) {
+      expression = node.expression;
+    }
+    if (expression == null) return;
+
+    var value = utils.getNodeText(expression);
+
+    await builder.addDartFileEdit(file, (builder) {
+      var libraryPrefix =
+          builder.importLibraryElement(Uri.parse('dart:async')).prefix;
+      var prefix = libraryPrefix != null ? '$libraryPrefix.' : '';
+      builder.addSimpleReplacement(
+        range.node(expression!),
+        '${prefix}unawaited($value)',
+      );
+    });
+  }
+}

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

@@ -1630,6 +1630,11 @@ class DartFixKind {
     DartFixKindPriority.DEFAULT,
     "Wrap in a 'Text' widget",
   );
+  static const WRAP_IN_UNAWAITED = FixKind(
+    'dart.fix.wrap.unawaited',
+    DartFixKindPriority.DEFAULT,
+    "Wrap in 'unawaited'",
+  );
 }
 
 class DartFixKindPriority {

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

@@ -194,6 +194,7 @@ import 'package:analysis_server/src/services/correction/dart/use_not_eq_null.dar
 import 'package:analysis_server/src/services/correction/dart/use_rethrow.dart';
 import 'package:analysis_server/src/services/correction/dart/wrap_in_future.dart';
 import 'package:analysis_server/src/services/correction/dart/wrap_in_text.dart';
+import 'package:analysis_server/src/services/correction/dart/wrap_in_unawaited.dart';
 import 'package:analysis_server/src/services/correction/fix.dart';
 import 'package:analysis_server/src/services/correction/util.dart';
 import 'package:analysis_server/src/services/linter/lint_names.dart';
@@ -449,6 +450,7 @@ class FixProcessor extends BaseProcessor {
     ],
     LintNames.discarded_futures: [
       AddAsync.new,
+      WrapInUnawaited.new,
     ],
     LintNames.empty_catches: [
       RemoveEmptyCatch.new,
@@ -625,6 +627,7 @@ class FixProcessor extends BaseProcessor {
     ],
     LintNames.unawaited_futures: [
       AddAwait.unawaited,
+      WrapInUnawaited.new,
     ],
     LintNames.unnecessary_brace_in_string_interps: [
       RemoveInterpolationBraces.new,

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

@@ -234,6 +234,7 @@ import 'use_not_eq_null_test.dart' as use_not_eq_null;
 import 'use_rethrow_test.dart' as use_rethrow;
 import 'wrap_in_future_test.dart' as wrap_in_future;
 import 'wrap_in_text_test.dart' as wrap_in_text;
+import 'wrap_in_unawaited_test.dart' as wrap_in_unawaited;
 
 void main() {
   defineReflectiveSuite(() {
@@ -438,5 +439,6 @@ void main() {
     use_rethrow.main();
     wrap_in_future.main();
     wrap_in_text.main();
+    wrap_in_unawaited.main();
   }, name: 'fix');
 }

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

@@ -0,0 +1,167 @@
+// 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: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_reflective_loader/test_reflective_loader.dart';
+
+import 'fix_processor.dart';
+
+void main() {
+  defineReflectiveSuite(() {
+    defineReflectiveTests(WrapInUnawaitedTest);
+    defineReflectiveTests(WrapDiscardedFutureInUnawaitedTest);
+  });
+}
+
+@reflectiveTest
+class WrapDiscardedFutureInUnawaitedTest extends FixProcessorLintTest {
+  @override
+  FixKind get kind => DartFixKind.WRAP_IN_UNAWAITED;
+
+  @override
+  String get lintCode => LintNames.discarded_futures;
+
+  Future<void> test_expressionStatement() async {
+    await resolveTestCode('''
+void f() {
+  g();
+}
+
+Future<void> g() async { }
+''');
+    await assertHasFix('''
+import 'dart:async';
+
+void f() {
+  unawaited(g());
+}
+
+Future<void> g() async { }
+''');
+  }
+}
+
+@reflectiveTest
+class WrapInUnawaitedTest extends FixProcessorLintTest {
+  @override
+  FixKind get kind => DartFixKind.WRAP_IN_UNAWAITED;
+
+  @override
+  String get lintCode => LintNames.unawaited_futures;
+
+  Future<void> test_expressionStatement() async {
+    await resolveTestCode('''
+Future<void> f() async {
+  g();
+}
+
+Future<void> g() async { }
+''');
+    await assertHasFix('''
+import 'dart:async';
+
+Future<void> f() async {
+  unawaited(g());
+}
+
+Future<void> g() async { }
+''');
+  }
+
+  Future<void> test_expressionStatement_prefixed() async {
+    newFile('$testPackageLibPath/g.dart', '''
+Future<void> g() async { }
+''');
+
+    await resolveTestCode('''
+import 'g.dart' as g_lib;
+
+Future<void> f() async {
+  g_lib.g();
+}
+''');
+    await assertHasFix('''
+import 'dart:async';
+
+import 'g.dart' as g_lib;
+
+Future<void> f() async {
+  unawaited(g_lib.g());
+}
+''');
+  }
+
+  Future<void> test_expressionStatement_prefixedImport() async {
+    await resolveTestCode('''
+import 'dart:async' as dart_async;
+
+dart_async.Future<void> f() async {
+  g();
+}
+
+dart_async.Future<void> g() async { }
+''');
+    await assertHasFix('''
+import 'dart:async' as dart_async;
+
+dart_async.Future<void> f() async {
+  dart_async.unawaited(g());
+}
+
+dart_async.Future<void> g() async { }
+''');
+  }
+
+  Future<void> test_expressionStatement_prefixedTarget() async {
+    newFile('$testPackageLibPath/g.dart', '''
+class C {
+  static Future<void> g() async { }
+}
+''');
+
+    await resolveTestCode('''
+import 'g.dart' as g_lib;
+
+Future<void> f() async {
+  g_lib.C.g();
+}
+''');
+    await assertHasFix('''
+import 'dart:async';
+
+import 'g.dart' as g_lib;
+
+Future<void> f() async {
+  unawaited(g_lib.C.g());
+}
+''');
+  }
+
+  Future<void> test_expressionStatement_target() async {
+    await resolveTestCode('''
+class C {
+  Future<void> g() async { }
+}
+
+Future<void> f() async {
+  var c = C();
+  c.g();
+}
+''');
+    await assertHasFix('''
+import 'dart:async';
+
+class C {
+  Future<void> g() async { }
+}
+
+Future<void> f() async {
+  var c = C();
+  unawaited(c.g());
+}
+''');
+  }
+}