analyzer: Allow awaitNotRequired on a Future-returning typedef

This includes bumping meta to 1.18.1.

To support flutter/flutter#168555

Change-Id: I6830a413efcf9939467e97faf58b1255d2d3d8eb
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/475760
Reviewed-by: Konstantin Shcheglov <scheglov@google.com>
Commit-Queue: Samuel Rawlins <srawlins@google.com>

Author: srawlins

pkg/analyzer/lib/src/error/annotation_verifier.dart

@@ -109,6 +109,8 @@ class AnnotationVerifier {
           errorNode: variable,
         );
       }
+    } else if (parent case GenericTypeAlias(functionType: var type?)) {
+      checkType(type.returnType?.type);
     } else {
       // Warning reported by `_checkKinds`.
     }

pkg/analyzer/test/src/diagnostics/invalid_await_not_required_annotation_test.dart

@@ -99,6 +99,17 @@ int x = 0;
     );
   }
 
+  test_invalid_typedef_intReturnType() async {
+    await assertErrorsInCode(
+      '''
+import 'package:meta/meta.dart';
+@awaitNotRequired
+typedef Td = int Function();
+''',
+      [error(diag.invalidAwaitNotRequiredAnnotation, 34, 16)],
+    );
+  }
+
   test_valid_field_futureReturnType() async {
     await assertNoErrorsInCode('''
 import 'package:meta/meta.dart';
@@ -189,6 +200,14 @@ class D extends C {
 import 'package:meta/meta.dart';
 @awaitNotRequired
 Future<int> x = Future.value(7);
+''');
+  }
+
+  test_valid_typedef_futureReturnType() async {
+    await assertNoErrorsInCode('''
+import 'package:meta/meta.dart';
+@awaitNotRequired
+typedef Td = Future<void> Function();
 ''');
   }
 }

pkg/analyzer_testing/lib/src/mock_packages/meta/meta.dart

@@ -124,6 +124,7 @@ class _AlwaysThrows {
   TargetKind.getter,
   TargetKind.method,
   TargetKind.topLevelVariable,
+  TargetKind.typedefType,
 })
 class _AwaitNotRequired {
   const _AwaitNotRequired();

pkg/linter/lib/src/extensions.dart

@@ -369,6 +369,17 @@ extension ExpressionExtension on Expression {
       PropertyAccess(:var propertyName) => propertyName.element,
       _ => null,
     };
+
+    // This handles `p();` where `p` is a parameter typed with a typedef which
+    // is annotated with `@awaitNotRequired`.
+    if (this case FunctionExpressionInvocation self) {
+      if (self.function.staticType?.alias case var alias?) {
+        if (alias.element.hasAwaitNotRequired) {
+          return true;
+        }
+      }
+    }
+
     if (element == null) return false;
     if (element.hasAwaitNotRequired) return true;
 

pkg/linter/test/rules/unawaited_futures_test.dart

@@ -182,6 +182,20 @@ Future<int> g() => Future.value(0);
 ''');
   }
 
+  test_functionCall_unawaited_awaitNotRequiredOnTypedef() async {
+    await assertNoDiagnostics(r'''
+import 'package:meta/meta.dart';
+void f(C c) async {
+  c.td();
+}
+@awaitNotRequired
+typedef Td = Future<void> Function();
+abstract class C {
+  Td td = () async {};
+}
+''');
+  }
+
   test_functionCallInCascade() async {
     await assertDiagnostics(
       r'''
@@ -325,6 +339,19 @@ void f(Future<int> p) async {
     );
   }
 
+  test_parameter_unawaited_awaitNotRequiredOnTypedef() async {
+    await assertNoDiagnostics(r'''
+import 'package:meta/meta.dart';
+
+@awaitNotRequired
+typedef Td = Future<void> Function();
+
+void f(Td p) async {
+  p();
+}
+''');
+  }
+
   test_prefixExpression_unawaited() async {
     await assertDiagnostics(
       r'''

pkg/meta/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 1.18.1
+
+- Allow `@awaitNotRequired` to annotate a typedef.
+
 ## 1.18.0
 
 - The `@redeclare` annotation is no longer considered experimental.

pkg/meta/lib/meta.dart

@@ -673,6 +673,7 @@ class _AlwaysThrows {
   TargetKind.getter,
   TargetKind.method,
   TargetKind.topLevelVariable,
+  TargetKind.typedefType,
 })
 class _AwaitNotRequired {
   const _AwaitNotRequired();

pkg/meta/pubspec.yaml

@@ -1,7 +1,7 @@
 name: meta
 # Note, because version `2.0.0` was mistakenly released,
 # the next major version must be `3.x.y`.
-version: 1.18.0
+version: 1.18.1
 description: >-
  Annotations used to express developer intentions that can't otherwise be
  deduced by statically analyzing source code.