SONARJAVA-4186 Fix S2134 to handle correctly unknown types

java-checks-test-sources/src/main/files/non-compiling/checks/ThreadOverridesRunCheck.java

@@ -0,0 +1,16 @@
+package checks;
+
+class ThreadOverridesRunCheck {
+  void foo(Runnable r) {
+    Thread t1 = new Thread(r) { // Compliant
+      void doSomething() { /* do nothing */ }
+    };
+
+    Thread t2 = new Thread(unknown) {
+      void doSomething() { /* do nothing */ }
+    };
+
+    Thread t3 = new Thread() { }; // Noncompliant
+  }
+
+}

java-checks/src/main/java/org/sonar/java/checks/ThreadOverridesRunCheck.java

@@ -90,11 +90,11 @@ private static boolean hasConstructorCallingSuperWithRunnable(ClassTree classTre
   }
 
   private static boolean hasRunnableArgument(Arguments args) {
-    return args.stream().anyMatch(ThreadOverridesRunCheck::isRunnable);
+    return args.stream().map(ExpressionTree::symbolType).anyMatch(ThreadOverridesRunCheck::isRunnable);
   }
 
-  private static boolean isRunnable(ExpressionTree arg) {
-    return arg.symbolType().isSubtypeOf("java.lang.Runnable");
+  private static boolean isRunnable(Type argType) {
+    return argType.isUnknown() || argType.isSubtypeOf("java.lang.Runnable");
   }
 
   private static boolean hasCallToSuperWithRunnable(MethodTree constructor) {

java-checks/src/test/java/org/sonar/java/checks/ThreadOverridesRunCheckTest.java

@@ -23,6 +23,7 @@
 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 ThreadOverridesRunCheckTest {
 
@@ -33,4 +34,12 @@ void detected() {
       .withCheck(new ThreadOverridesRunCheck())
       .verifyIssues();
   }
+
+  @Test
+  void non_compiling() {
+    CheckVerifier.newVerifier()
+      .onFile(nonCompilingTestSourcesPath("checks/ThreadOverridesRunCheck.java"))
+      .withCheck(new ThreadOverridesRunCheck())
+      .verifyIssues();
+  }
 }