Cucumber testng with PowerMockTestCase to mock static classes - cucumber

Question

I am using cucumber BDD, testng, java to write some BDD test. I would like to mock static classes in order to write my test. However when I write this testrunner, it fails to initialize the BDD scenarios.
Complete Example(note the commented line PrepareForTest) :
import gherkin.events.PickleEvent;
import io.cucumber.testng.CucumberOptions;
import io.cucumber.testng.PickleEventWrapper;
import io.cucumber.testng.TestNGCucumberRunner;
import org.powermock.api.mockito.PowerMockito;
import org.powermock.core.classloader.annotations.PrepareForTest;
import org.powermock.modules.testng.PowerMockTestCase;
import org.testng.Assert;
import org.testng.annotations.BeforeClass;
import org.testng.annotations.DataProvider;
import org.testng.annotations.Test;
import java.util.concurrent.TimeUnit;
import static org.mockito.Matchers.any;
#CucumberOptions(
features = {
"src/test/resources/features/sample"
},
glue = {
"com.demo.stepdefinitions.sample"
},
plugin = {
"pretty",
"html:target/cucumber-reports/cucumber-pretty",
"json:target/cucumber-reports/sampple-report.json",
"rerun:target/cucumber-reports/sample-rerun.txt"
}
)
//#PrepareForTest({Util.class})
public class TestngWithDataproviderTest extends PowerMockTestCase {
private TestNGCucumberRunner testNGCucumberRunner;
private void mockActiveBucket() {
PowerMockito.mockStatic(Util.class);
PowerMockito.when(Util.getBucketId(any(Long.class))).thenReturn(3);
}
#BeforeClass(alwaysRun = true)
public void setUpClass() throws Exception {
testNGCucumberRunner = new TestNGCucumberRunner(this.getClass());
}
#Test(dataProvider = "users")
public void testMockStatic(String username){
System.out.println("username: " + username);
System.out.println("static test passed");
mockActiveBucket();
Assert.assertTrue(true);
}
#Test(groups = "cucumber scenarios", description = "Runs Cucumber Scenarios", dataProvider = "scenarios")
public void testCucumberCcenario(PickleEventWrapper pickleEvent) throws Throwable {
PickleEvent event = pickleEvent.getPickleEvent();
mockActiveBucket();
testNGCucumberRunner.runScenario(pickleEvent.getPickleEvent());
Assert.assertTrue(true);
}
#DataProvider(name = "scenarios")
public Object[][] scenarios() {
Object[][] scenarios = testNGCucumberRunner.provideScenarios();
return new Object[][]{{scenarios[0][0]}};
}
#DataProvider(name = "users")
public Object[][] users() {
return new Object[][]{{"user1"}, {"user2"}};
}
}
class Util {
public static int getBucketId(long eventTimestamp){
Long minsPast5MinBoundary = (eventTimestamp % TimeUnit.MINUTES.toMillis(5))/TimeUnit.MINUTES.toMillis(1);
return minsPast5MinBoundary.intValue();
}
}
The above test fails to load BDD scenarios dataProvider if I enable PrepareForTest annotation on the test. However, the other test which uses dataProvider works fine in both cases(enable or disable PrepareForTest)
ERROR:
Data provider mismatch
Method: testCucumberCcenario([Parameter{index=0, type=io.cucumber.testng.PickleEventWrapper, declaredAnnotations=[]}])
Arguments: [(io.cucumber.testng.PickleEventWrapperImpl) "Sunday isn't Friday"]
at org.testng.internal.reflect.DataProviderMethodMatcher.getConformingArguments(DataProviderMethodMatcher.java:45)
at org.testng.internal.Parameters.injectParameters(Parameters.java:796)
at org.testng.internal.Invoker.invokeTestMethods(Invoker.java:983)
at org.testng.internal.TestMethodWorker.invokeTestMethods(TestMethodWorker.java:125)
at org.testng.internal.TestMethodWorker.run(TestMethodWorker.java:109)
at org.testng.TestRunner.privateRun(TestRunner.java:648)
at org.testng.TestRunner.run(TestRunner.java:505)
As a side effect of this, I am unable to mock static methods of util class while writing the BDD. I am new to cucumber BDD. Any help/pointers is appreciated.

Answer 1

After getting some help to root cause from #help-cucumber-jvm slack channel, I was able to root cause it to testng+powermock with dataproviders using custom classes.
For example this test fails
import org.powermock.api.mockito.PowerMockito;
import org.powermock.core.classloader.annotations.PrepareForTest;
import org.powermock.modules.testng.PowerMockTestCase;
import org.testng.Assert;
import org.testng.annotations.DataProvider;
import org.testng.annotations.ObjectFactory;
import org.testng.annotations.Test;
import java.io.IOException;
import java.util.concurrent.TimeUnit;
import static org.mockito.Matchers.any;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.ObjectWriter;
#PrepareForTest(Util2.class)
public class TestngWithDataproviderTestngTest extends PowerMockTestCase {
#ObjectFactory
public org.testng.IObjectFactory getObjectFactory() {
return new org.powermock.modules.testng.PowerMockObjectFactory();
}
private void mockActiveBucket() {
PowerMockito.mockStatic(Util.class);
PowerMockito.when(Util.getBucketId(any(Long.class))).thenReturn(3);
}
#Test(dataProvider = "users")
public void testMockStatic(MyTestCaseImpl myTestCase) {
System.out.println("myTestCase: " + myTestCase);
System.out.println("static test passed");
mockActiveBucket();
Assert.assertTrue(true);
}
#DataProvider(name = "users")
public Object[][] users() {
return new Object[][]{{new MyTestCaseImpl(5)}};
}
}
//interface MyTestCase {
//}
class MyTestCaseImpl { //implements MyTestCase{
int i;
public MyTestCaseImpl() {
}
public MyTestCaseImpl(int i) {
this.i = i;
}
public int getI() {
return i;
}
public void setI(int i) {
this.i = i;
}
}
class Util2 {
public static int getBucketId(long eventTimestamp) {
Long minsPast5MinBoundary = (eventTimestamp % TimeUnit.MINUTES.toMillis(5)) / TimeUnit.MINUTES.toMillis(1);
return minsPast5MinBoundary.intValue();
}
}
Here as mentioned, seems to be a known issue with a workaround. Hope this helps.