Importing content from JSON using wcm.io AEM Mocks with a real Jackrabbit implementation

I'm trying to write an integration test using wcm.io Testing AEM Mocks

The code I want to test saves some data in the repository so I would like to verify if the right content is actually stored after I run a tested method.

In my previous tests, I used the JCR_MOCK Resource Resolver Type, like this:

@RunWith(MockitoJUnitRunner.class)
public class MyClassTest {

    @Rule
    public final AemContext aemContext = new AemContext(ResourceResolverType.JCR_MOCK);

    private MyClass tested;

    @Before
    public void setUp() throws Exception {

        //here, I load an entire page,
        //from which my tested class reads some data
        aemContext.load().json("/jcrdata/myPage.json", "/etc/mystuff/myTool");

        tested = new MyClass(aemContext.resourceResolver());
    }

    @Test
    public void interactWithTheRepository() {

        SomeResult result = tested.interactWithTheRepository();

        //assertions here
    }
}

This works just fine as long as I just want to read data from the mock repository or pretend I save something. The problem starts when I actually want to verify that some data has been persisted in the repository by the tested class.

@RunWith(MockitoJUnitRunner.class)
public class MyClassTest {

    @Rule
    public final AemContext aemContext = new AemContext(ResourceResolverType.JCR_MOCK);

    private MyClass tested;

    @Before
    public void setUp() throws Exception {

        //here, I load an entire page,
        //on which the instance of my tested class later saves some data
        aemContext.load().json("/jcrdata/myPage.json", "/etc/mystuff/myTool");

        tested = new MyClass(aemContext.resourceResolver());
    }

    @Test
    public void storeDataInTheRepository() {

        tested.storeDataInTheRepository();

        //this comes up as null because the JCR_Mock resolver
        //does not use an actual repository and nothing is stored
        Resource result = aemContext.resourceResolver().getResource("/etc/mystuff/myTool/somethingSavedByMyClassInstance");

        //assertions here
    }
}

I believe this can achieved with the JCR_JACKRABBIT Resource Resolver Type, which uses an actual repository. However, I'm having a hard time loading the data into the mock repository. As soon as I use JCR_JACKRABBIT instaed of JCR_MOCK, my setUp method fails with a NullPointerException (other parts of the class omitted for clarity)

    @Rule
    public final AemContext aemContext = new AemContext(ResourceResolverType.JCR_JACKRABBIT);

    @Before
    public void setUp() throws Exception {

        //This line fails with an NPE
        aemContext.load().json("/jcrdata/myPage.json", "/etc/mystuff/myTool");

        tested = new MyClass(aemContext.resourceResolver());
    }

I debugged the code and noticed that it fails while trying to create the resource hierarchy.

java.lang.NullPointerException
    at org.apache.sling.resourceresolver.impl.ResourceResolverImpl.create(ResourceResolverImpl.java:1044)
    at org.apache.sling.testing.mock.sling.loader.ContentLoader.createResourceHierarchy(ContentLoader.java:183)
    at org.apache.sling.testing.mock.sling.loader.ContentLoader.createResourceHierarchy(ContentLoader.java:178)
    at org.apache.sling.testing.mock.sling.loader.ContentLoader.json(ContentLoader.java:155)
    at org.apache.sling.testing.mock.sling.loader.ContentLoader.json(ContentLoader.java:120)
    at com.foo.bar.baz.MyClassTest.setUp(MyClassTest.java:35)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:601)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)
    at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:24)
    at org.junit.rules.ExternalResource$1.evaluate(ExternalResource.java:48)
    at org.junit.rules.RunRules.evaluate(RunRules.java:20)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
    at org.mockito.internal.runners.JUnit45AndHigherRunnerImpl.run(JUnit45AndHigherRunnerImpl.java:37)
    at org.mockito.runners.MockitoJUnitRunner.run(MockitoJUnitRunner.java:62)
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)

According to the documentation, Sling Testing should handle the creation of all parent resources while trying to load a page from a JSON document:

Resource org.apache.sling.testing.mock.sling.loader.ContentLoader.json(String classpathResource, String destPath)

Import content of JSON file into repository. Auto-creates parent hierarchies as nt:unstrucured nodes if missing.

However, when the root of the repository is reached and an etc node is supposed to be created under /, the ContentLoader's method createResourceHierarchy calls the ResourceResolver with the following parameters:

resourceResolver.create(null, ResourceUtil.getName("/etc"), props);

where props is a simple HashMap of the following structure: {jcr:primaryType=nt:unstructured}, causing a NullPointerException (due to a null parent resource being passed)

I'm not sure if this is a bug or something I'm doing wrong, the Sling Testing documentation mentions this about the JCR_JACKRABBIT Resource Resolver type:

To import Sling content you have to fully register all node types required for the data

but I'm not sure how to interpret this.

I'm using:

• io.wcm.testing.aem-mock 1.2.2


• org.apache.sling.testing.sling-mock-jackrabbit 0.1.0

How can I load content from a JSON file when using the JCR_JACKRABBIT Resource Resolver implementation?