SONARJAVA-6179 Fix FP on S6810 when semantic information is missing

java-checks-test-sources/default/src/main/files/non-compiling/checks/spring/AsyncMethodsReturnTypeCheckSample.java

@@ -0,0 +1,35 @@
+package checks.spring;
+
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.Future;
+import org.springframework.scheduling.annotation.Async;
+
+public class AsyncMethodsReturnTypeCheckSample {
+
+  @Async
+  public CompletableFuture<Data> unknownTypeArg() { // Compliant
+    return CompletableFuture.completedFuture(new Data());
+  }
+
+  @Async
+  public void voidType() { // Compliant
+    return;
+  }
+
+  @Async
+  public CompletableFuture<Integer> futureSubtype() { // Compliant
+    return CompletableFuture.completedFuture(42);
+  }
+
+  @Async
+  public Data unknownType() { // Compliant, no issue is raised when the return type is unknown (it might be a subtype of Future)
+    return new Data();
+  }
+
+  @Async
+  public Integer builtinType() { // Noncompliant {{Async methods should return 'void' or a 'Future' type.}}
+//       ^^^^^^^
+    return 42;
+  }
+
+}

java-checks/src/main/java/org/sonar/java/checks/spring/AsyncMethodsReturnTypeCheck.java

@@ -20,8 +20,10 @@
 import org.sonar.check.Rule;
 import org.sonar.java.checks.helpers.SpringUtils;
 import org.sonar.plugins.java.api.IssuableSubscriptionVisitor;
+import org.sonar.plugins.java.api.semantic.Type;
 import org.sonar.plugins.java.api.tree.MethodTree;
 import org.sonar.plugins.java.api.tree.Tree;
+import org.sonar.plugins.java.api.tree.TypeTree;
 
 @Rule(key = "S6810")
 public class AsyncMethodsReturnTypeCheck extends IssuableSubscriptionVisitor {
@@ -35,12 +37,14 @@ public List<Tree.Kind> nodesToVisit() {
   public void visitNode(Tree tree) {
     var mt = (MethodTree) tree;
     if (mt.symbol().metadata().isAnnotatedWith(SpringUtils.ASYNC_ANNOTATION)) {
-      var returnType = mt.returnType();
+      TypeTree returnType = mt.returnType();
       // returnType can only be null if the method is a constructor. Since the @Async annotation is not allowed on constructors, and since
       // we hence only visit methods, not constructors, we assume that returnType is not null.
-      if (!returnType.symbolType().isVoid() && !returnType.symbolType().isSubtypeOf("java.util.concurrent.Future")) {
-        reportIssue(returnType, "Async methods should return 'void' or a 'Future' type.");
+      Type symbolType = returnType.symbolType();
+      if (symbolType.isUnknown() || symbolType.isVoid() || symbolType.isSubtypeOf("java.util.concurrent.Future")) {
+        return;
       }
+      reportIssue(returnType, "Async methods should return 'void' or a 'Future' type.");
     }
   }
 }

java-checks/src/test/java/org/sonar/java/checks/spring/AsyncMethodsReturnTypeCheckTest.java

@@ -20,6 +20,7 @@
 import org.sonar.java.checks.verifier.CheckVerifier;
 
 import static org.sonar.java.checks.verifier.TestUtils.mainCodeSourcesPath;
+import static org.sonar.java.checks.verifier.TestUtils.nonCompilingTestSourcesPath;
 
 class AsyncMethodsReturnTypeCheckTest {
   @Test
@@ -29,4 +30,12 @@ void test() {
       .withCheck(new AsyncMethodsReturnTypeCheck())
       .verifyIssues();
   }
+
+  @Test
+  void test_non_compiling() {
+    CheckVerifier.newVerifier()
+      .onFile(nonCompilingTestSourcesPath("checks/spring/AsyncMethodsReturnTypeCheckSample.java"))
+      .withCheck(new AsyncMethodsReturnTypeCheck())
+      .verifyIssues();
+  }
 }