Mockito Mocking Android Context PackageManager Exception

Question

我从mokito for Android headless Unit Test开始。我想测试的部分是在后端，它依赖于Context。我试着模拟Context，但当我运行测试时，我得到null。

在这个例子中看到的模拟Context并没有告诉我它是如何被模拟的:https://developer.android.com/training/testing/unit-testing/local-unit-tests.html设置

上面链接中提到的示例(https://github.com/googlesamples/android-testing/tree/master/unit/BasicSample)没有关于如何模拟上下文的示例。

所以我有点迷路了。

我的gradle依赖项中有以下内容:

testCompile 'junit:junit:4.12'
androidTestCompile 'com.android.support.test:runner:0.4'
androidTestCompile 'com.android.support.test:rules:0.4'
androidTestCompile 'com.android.support:support-annotations:23.0.1'
testCompile 'org.mockito:mockito-core:1.10.19'
androidTestCompile('com.android.support.test:testing-support-lib:0.+')

代码片段:

@RunWith(MockitoJUnitRunner.class)
public static Test {
  @Mock Context mContext;
  RequestQueue mQueue;
@Test public void getCategories(){
final String SERVER = "http://{...}/categories";
mContext = mock(Context.class);
int size = 20;
when(mContext.getResources().getInteger(R.integer.cache_size)).thenReturn(size);
mQueue = VolleyUtil.newRequestQueue(mContext, null, size);
final Response.Listener<String> listener = new Response.Listener(){
//...
}
Response.ErrorListener error = new Response.ErrorListener(){
///...
}
mQueue.add(new JsonRequest(SERVER, listener, error);
}
VolleyUtil.newRequestQueue(final Context context, HttpStack stack, final int cacheMB){
final File cacheDir = new File(context.getCacheDir(), "volley");
  if(stack == null) {
     if(Build.VERSION.SDK_INT >= 9) {
        stack = new HurlStack();
     } else {
        String userAgent = "volley/0";
        try {
           final String network = context.getPackageName();
           final PackageInfo queue = context.getPackageManager().getPackageInfo(network, 0);
           userAgent = network + "/" + queue.versionCode;
        } catch (PackageManager.NameNotFoundException e) {
           e.printStacktrace();
        }
        stack = new HttpClientStack(AndroidHttpClient.newInstance(userAgent));
     }
  }
  final BasicNetwork network = new BasicNetwork((HttpStack)stack);
  final RequestQueue queue = new RequestQueue(new DiskBasedCache(cacheDir,diskCacheMB*1000000), network);
  queue.start();
  return queue;

}

我的null异常发生在:

final PackageInfo queue = context.getPackageManager().getPackageInfo(network, 0);

我应该模拟PackageManager或Application实例吗?

Answer 1

因为您没有在JUnit上测试android资源，所以您也需要模拟这个。例如:

PackageInfo pi = new PackgeInfo();
// modify it's value the way you desire
when(mContext.getPackageManager().getPackageInfo(network, 0)).thenReturn(pi);