fix: make avoid-redundant-async handle yield (#1021)

Author: incendial

CHANGELOG.md

@@ -6,6 +6,7 @@
 * chore: changed min `SDK` version to `2.18.0`.
 * chore: restrict `analyzer` version to `>=5.1.0 <5.2.0`.
 * chore: restrict `analyzer_plugin` version to `>=0.11.0 <0.12.0`.
+* fix: make [`avoid-redundant-async`](https://dartcodemetrics.dev/docs/rules/common/avoid-redundant-async) correctly handle yield.
 
 ## 4.19.1
 

lib/src/analyzers/lint_analyzer/rules/rules_list/avoid_redundant_async/visitor.dart

@@ -73,4 +73,11 @@ class _AsyncVisitor extends RecursiveAstVisitor<void> {
 
     hasValidAsync = true;
   }
+
+  @override
+  void visitYieldStatement(YieldStatement node) {
+    super.visitYieldStatement(node);
+
+    hasValidAsync = true;
+  }
 }

test/src/analyzers/lint_analyzer/rules/rules_list/avoid_redundant_async/examples/example.dart

@@ -34,4 +34,10 @@ class SomeClass {
   Future<void> returnNullable(SomeClass? instance) async {
     return instance?.report([]);
   }
+
+  Stream<int> buildStream() async* {
+    for (int i = 0; i < 10; i++) {
+      yield i;
+    }
+  }
 }