Unit Testing A Network Response. Works When Debugging, Not When Actually Running

I am currently attempting to test that a network response is actually being received. While I understand that this isn't what I should be doing with regards to testing, its a curio

Solution 1:

Volley relies on Looper.getMainLooper() to handle its executions. When using a RobolectricTestRunner, Robolectric mocks this out and as such it will not be correctly set up, thus resulting in a failed test.

In my specific case, when I was using breakpoints, the system actually does set up the main looper, because the system is utilizing it to show the breakpoints / debugging tools. This thus describes the reasoning behind the behaviour found in my initial question.

Now for a solution as to getting real network responses with Volley during a unit test, the executor must be changed to not be using the main looper.

As an easy solution, create a request queue that relies on Executor.singleThreadExecutor() instead of the Main Looper.

Here is what I mean:

//Specific test queue that uses a singleThreadExecutor instead of the mainLooper for testing purposes.public RequestQueue newVolleyRequestQueueForTest(final Context context) {
    FilecacheDir=newFile(context.getCacheDir(), "cache/volley");
    Networknetwork=newBasicNetwork(newHurlStack());
    ResponseDeliveryresponseDelivery=newExecutorDelivery(Executors.newSingleThreadExecutor());
    RequestQueuequeue=newRequestQueue(newDiskBasedCache(cacheDir), network, 4, responseDelivery);
    queue.start();
    return queue;
}

Then, use that as your request queue for Volley during the tests.

The key here is:

ResponseDelivery responseDelivery = new ExecutorDelivery(Executors.newSingleThreadExecutor());

Hope this helps!