在 Android 的导航组件中测试导航操作

Question

最近我将导航组件集成到一个项目中，该项目是基于单个 activity 模型的 uild。我尝试根据 android 文档中的教程添加 ui 测试。但是，当我对该教程进行了一些修改时，它没有用。我的片段中有以下代码。

val bundle = Bundle().apply {
   putString(UserTrackingConstants.VIEW, UserTrackingConstants.HOME)
}

btnSignUp.setOnClickListener {
findNavController().navigate(R.id.action_from_home_fragment_to_registration_fragment,bundle)
}

因此，只要单击 btnSignUp，它就会调用以下导航操作。它工作完美。然后我添加了以下测试。

@Test
    fun testRegisterButtonClicked() {
        val mockNavController = mock(NavController::class.java)
        val bundle = bundleOf(
                UserTrackingConstants.VIEW to UserTrackingConstants.HOME
        )
        val scenario = launchFragmentInContainer<HomeFragment>()
        scenario.onFragment { fragment ->
            Navigation.setViewNavController(fragment.requireView(), mockNavController)
        }
        onView(withId(R.id.btnSignUp))
                .perform(click())
        verify(mockNavController).navigate(R.id.action_from_home_fragment_to_registration_fragment, bundle)
    }

并且抛出以下异常

E/TestRunner: ----- begin exception -----
    Argument(s) are different! Wanted:
    navController.navigate(
        2131296310,
        Bundle[{view=home}]
    );
    -> at HomeFragmentTest.testRegisterButtonClicked(HomeFragmentTest.kt:87)
    Actual invocation has different arguments:
    navController.navigate(
        2131296310,
        Bundle[{view=home}]
    );
    -> at HomeFragment$setupObservers.onClick(HomeFragment.kt:84)

        at HomeFragmentTest.testRegisterButtonClicked(HomeFragmentTest.kt:87)
        at java.lang.reflect.Method.invoke(Native Method)
        at org.junit.runners.model.FrameworkMethod.runReflectiveCall(FrameworkMethod.java:50)
        at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
        at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
        at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
        at androidx.test.internal.runner.junit4.statement.RunBefores.evaluate(RunBefores.java:80)
        at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
        at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
        at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
        at org.junit.runners.ParentRunner.run(ParentRunner.java:290)
        at org.junit.runners.ParentRunner.schedule(ParentRunner.java:71)
        at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
        at org.junit.runners.ParentRunner.access[=13=]0(ParentRunner.java:58)
        at org.junit.runners.ParentRunner.evaluate(ParentRunner.java:268)
        at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
        at androidx.test.ext.junit.runners.AndroidJUnit4.run(AndroidJUnit4.java:104)
        at org.junit.runners.Suite.runChild(Suite.java:128)
        at org.junit.runners.Suite.runChild(Suite.java:27)
        at org.junit.runners.ParentRunner.run(ParentRunner.java:290)
        at org.junit.runners.ParentRunner.schedule(ParentRunner.java:71)
        at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
        at org.junit.runners.ParentRunner.access[=13=]0(ParentRunner.java:58)
        at org.junit.runners.ParentRunner.evaluate(ParentRunner.java:268)
        at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
        at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
        at org.junit.runner.JUnitCore.run(JUnitCore.java:115)
        at androidx.test.internal.runner.TestExecutor.execute(TestExecutor.java:56)
        at androidx.test.runner.AndroidJUnitRunner.onStart(AndroidJUnitRunner.java:392)
        at android.app.Instrumentation$InstrumentationThread.run(Instrumentation.java:2189)
    ----- end exception -----

Argument(s) are different! Wanted:
navController.navigate(
2131296310,
Bundle[{view=home}]
);
-> at HomeFragmentTest.testRegisterButtonClicked(HomeFragmentTest.kt:87)
Actual invocation has different arguments:
navController.navigate(
2131296310,
Bundle[{view=home}]
);
-> at HomeFragment$setupObservers.onClick(HomeFragment.kt:84)

at HomeFragmentTest.testRegisterButtonClicked(HomeFragmentTest.kt:87)
at java.lang.reflect.Method.invoke(Native Method)
at org.junit.runners.model.FrameworkMethod.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at androidx.test.internal.runner.junit4.statement.RunBefores.evaluate(RunBefores.java:80)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
at org.junit.runners.ParentRunner.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access[=13=]0(ParentRunner.java:58)
at org.junit.runners.ParentRunner.evaluate(ParentRunner.java:268)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at androidx.test.ext.junit.runners.AndroidJUnit4.run(AndroidJUnit4.java:104)
at org.junit.runners.Suite.runChild(Suite.java:128)
at org.junit.runners.Suite.runChild(Suite.java:27)
at org.junit.runners.ParentRunner.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access[=13=]0(ParentRunner.java:58)
at org.junit.runners.ParentRunner.evaluate(ParentRunner.java:268)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
at org.junit.runner.JUnitCore.run(JUnitCore.java:115)
at androidx.test.internal.runner.TestExecutor.execute(TestExecutor.java:56)
at androidx.test.runner.AndroidJUnitRunner.onStart(AndroidJUnitRunner.java:392)
at android.app.Instrumentation$InstrumentationThread.run(Instrumentation.java:2189)

我没有从 logcat 中得到任何有用的信息。似乎争论是一样的，应该通过。如果我不通过 bundle，它工作正常。我遵循了以下 link https://developer.android.com/guide/navigation/navigation-testing 中的文档。我的问题是有没有人遇到过这样的异常以及如何使用 bundle 测试导航组件？

Answer 1

你遇到如此奇怪的测试结果的原因是 Bundle class 没有覆盖 equals() 和 toString() 方法，所以 Bundle 个实例通过引用进行比较（对于您预期的包和实际的包，引用明显不同）——由于 Mockito 依赖这些方法来验证对象是否相同，因此您的测试用例将失败。

要解决此问题，您可以为 Mockito.verify():

使用自定义匹配器

public class BundleEquals implements ArgumentMatcher, ContainsExtraTypeInfo, Serializable {

    @Nullable
    private final Bundle expected;

    public BundleEquals(@Nullable Bundle expected) {
        this.expected = expected;
    }

    @Override
    public boolean matches(Bundle actual) {
        if (expected == null && actual == null) {
            return true;
        }

        if (expected == null || actual == null) {
            return false;
        }

        return areBundlesEqual(expected, actual);
    }

    private boolean areBundlesEqual(@NonNull Bundle expected, @NonNull Bundle actual) {
        if (expected.size() != actual.size()) {
            return false;
        }

        if (!expected.keySet().containsAll(actual.keySet())) {
            return false;
        }

        for (String key : expected.keySet()) {
            @Nullable Object expectedValue = expected.get(key);
            @Nullable Object actualValue = actual.get(key);

            if (expectedValue instanceof Bundle && actualValue instanceof Bundle) {
                if (!areBundlesEqual((Bundle) expectedValue, (Bundle) actualValue)) {
                    return false;
                }
            } else if (!Objects.equals(expectedValue, actualValue)) {
                return false;
            }
        }

        return true;
    }

    public String toStringWithType() {
        String clazz = expected != null ? expected.getClass().getSimpleName() : null;
        return "(" + clazz + ") " + describe(expected);
    }

    private String describe(Object object) {
        return ValuePrinter.print(object);
    }

    @Override
    public boolean typeMatches(Object actual) {
        return expected != null && actual != null && actual.getClass() == expected.getClass();
    }

    public String toString() {
        return describe(expected);
    }

}

注意： ContainsExtraTypeInfo 和 Serializable 实现这里不需要，但是他们会在测试时为您提供详细的预期和实际参数描述由于捆绑包不匹配而失败，

要应用匹配器，你应该使用这样的东西：

verify(mockNavController).navigate(eq(R.id.action_from_home_fragment_to_registration_fragment), argThat(new BundleEquals(bundle));

注意这里需要 eq() 以使 Mockito 不会混淆不同的匹配器：将您的操作 ID 展开将无法验证。

在 Android 的导航组件中测试导航操作

Testing navigation action in navigation component in Android

android

ui-testing

android-mvvm

android-architecture-navigation