ensure array is not accepted as functional interface (IDEA-172048)

java/java-psi-api/src/com/intellij/psi/LambdaUtil.java

@@ -112,7 +112,7 @@ public class LambdaUtil {
     if (type instanceof PsiIntersectionType) {
       return extractFunctionalConjunct((PsiIntersectionType)type) != null;
     }
-    return isFunctionalClass(PsiUtil.resolveGenericsClassInType(type).getElement());
+    return isFunctionalClass(PsiUtil.resolveClassInClassTypeOnly(type));
   }
 
   @Contract("null -> false")

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/newLambda/ArrayNotAFunctionalInterface.java

+
+import java.util.concurrent.Callable;
+
+class Test {
+  public static <T> void execute(Callable<T>[] cmds) { }
+
+  public static void main(String[] args) throws Exception{
+    execute(<error descr="Callable<T>[] is not a functional interface">() -> null</error>);
+  }
+}

java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/NewLambdaHighlightingTest.java

@@ -156,6 +156,7 @@ public class NewLambdaHighlightingTest extends LightDaemonAnalyzerTestCase {
   public void testNestedLambdasWithInferenceOfReturnTypeInTheLatestLambda() { doTest(); }
   public void testCapturedWildcardNotOpenedDuringInference() { doTest(); }
   public void testIgnoreStandaloneExpressionsInLambdaReturnForNestedCalls() { doTest(); }
+  public void testArrayNotAFunctionalInterface() { doTest(); }
 
   private void doTest() {
     IdeaTestUtil.setTestVersion(JavaSdkVersion.JDK_1_8, getModule(), getTestRootDisposable());