NullPointerException at test with timeOut

Closes testng-team#2251

CHANGES.txt

@@ -1,4 +1,5 @@
 Current
+Fixed: GITHUB-2251: NullPointerException at test with timeOut (Krishnan Mahadevan)
 Fixed: GITHUB-2249: Not abstract super-classes mess up test run order (Sergii Kim)
 Fixed: GITHUB-2195: NPE Using groups and @Before/@AfterMethod with alwaysRun and dependsOnMethods (Tomas & Julien Herr)
 Fixed: GITHUB-2238: Parameter values should be overridable from JVM arguments (Krishnan Mahadevan)

src/main/java/org/testng/internal/InvokeMethodRunnable.java

@@ -50,7 +50,11 @@ private void runOne() {
               m_instance, m_parameters, m_hookable, m.getMethod(), m_testResult);
         }
       } catch (Throwable e) {
-        t = new TestNGRuntimeException(e.getCause());
+        Throwable cause = e.getCause();
+        if (cause == null) {
+          cause = e;
+        }
+        t = new TestNGRuntimeException(cause);
       }
       if (null != t) {
         Thread.currentThread().interrupt();

src/test/java/test/hook/issue2251/AbstractBaseTestCase.java

@@ -0,0 +1,42 @@
+package test.hook.issue2251;
+
+import java.lang.reflect.InvocationTargetException;
+import org.testng.IHookCallBack;
+import org.testng.IHookable;
+import org.testng.ITestResult;
+
+/**
+ * This test class apes on a bare essential What Spring TestNG provides as a base class in terms of
+ * running Spring based tests. The following methods have been duplicated from
+ * org.springframework.test.context.testng.AbstractTestNGSpringContextTests to simulate the bug. 1.
+ * throwAsUncheckedException() 2. getTestResultException() 3. throwAs()
+ */
+public class AbstractBaseTestCase implements IHookable {
+
+  @Override
+  public void run(IHookCallBack callBack, ITestResult testResult) {
+    callBack.runTestMethod(testResult);
+    Throwable t = getTestResultException(testResult);
+    if (t != null) {
+      throwAsUncheckedException(t);
+    }
+  }
+
+  @SuppressWarnings("unchecked")
+  private <T extends Throwable> void throwAs(Throwable t) throws T {
+    throw (T) t;
+  }
+
+  private void throwAsUncheckedException(Throwable t) {
+    throwAs(t);
+  }
+
+
+  private Throwable getTestResultException(ITestResult testResult) {
+    Throwable testResultException = testResult.getThrowable();
+    if (testResultException instanceof InvocationTargetException) {
+      testResultException = testResultException.getCause();
+    }
+    return testResultException;
+  }
+}

src/test/java/test/hook/issue2251/IssueTest.java

@@ -0,0 +1,21 @@
+package test.hook.issue2251;
+
+import org.assertj.core.api.Assertions;
+import org.testng.TestListenerAdapter;
+import org.testng.TestNG;
+import org.testng.annotations.Test;
+import test.SimpleBaseTest;
+
+public class IssueTest extends SimpleBaseTest {
+
+  @Test(description = "GITHUB-2251")
+  public void runTest() {
+    TestNG testng = create(SampleTestCase.class);
+    TestListenerAdapter l = new TestListenerAdapter();
+    testng.addListener(l);
+    testng.run();
+    Throwable t = l.getFailedTests().get(0).getThrowable();
+    Assertions.assertThat(t).isInstanceOf(NullPointerException.class);
+  }
+
+}

src/test/java/test/hook/issue2251/SampleTestCase.java

@@ -0,0 +1,19 @@
+package test.hook.issue2251;
+
+import org.testng.annotations.Test;
+
+public class SampleTestCase extends AbstractBaseTestCase {
+
+  static class NullExObj {
+
+    @Override
+    public String toString() {
+      throw new NullPointerException("expected");
+    }
+  }
+
+  @Test(timeOut = 1000000) //removing timeout fixes error output
+  public void testError() throws Exception {
+    new NullExObj().toString();
+  }
+}

src/test/resources/testng.xml

@@ -627,6 +627,7 @@
   <test name="Hookable" >
     <classes>
       <class name="test.hook.HookableTest"/>
+      <class name="test.hook.issue2251.IssueTest"/>
     </classes>
   </test>