JUnit4 - AssertionFailedError: No tests found

Question

I'm using AndroidJUnitRunner with Espresso.

I wrote a simple test but always receive this exception. According to Stackoverflow answers, the problem is messing up the JUnit3 and JUnit4 but I have never used JUnit3 in my project.

junit.framework.AssertionFailedError: No tests found in com.walletsaver.app.test.espresso.SignUpPopupTest

package com.walletsaver.app.test.espresso;

import android.support.test.rule.ActivityTestRule;
import android.support.test.runner.AndroidJUnit4;
import android.test.suitebuilder.annotation.SmallTest;

import com.walletsaver.app.activity.LoginActivity;

import org.junit.Rule;
import org.junit.Test;
import org.junit.runner.RunWith;

import static android.support.test.espresso.Espresso.onView;
import static android.support.test.espresso.action.ViewActions.click;
import static android.support.test.espresso.matcher.ViewMatchers.withText;

@RunWith(AndroidJUnit4.class)
@SmallTest
public class SignUpPopupTest {

    @Rule
    public ActivityTestRule<LoginActivity> mActivityRule =
            new ActivityTestRule<>(LoginActivity.class);

    @Test
    public void checkSignUpPopup() throws Exception {
        onView(withText("Sign Up")).perform(click());
    }
}

Run configuration:

Output:

Solution 1

I found the problem. It was missed code in build.gradle in the main module. If you have this problem I advise to start with adding this line:

android {
    ...

    defaultConfig {
        ...

        testInstrumentationRunner 'android.support.test.runner.AndroidJUnitRunner'
    }
...
}

Solution 2

android {
    defaultConfig {
        testInstrumentationRunner 'android.support.test.runner.AndroidJUnitRunner'
    }
}

dependencies {
    androidTestImplementation "androidx.test:runner:1.4.0"
    androidTestImplementation "androidx.test.ext:junit:1.1.3"
}

---

@RunWith(AndroidJUnit4::class)
class SomeInstrumentedTest {}

Comments

[Omer Malik]

Thanks alot it solved the problem, can you tell why we have to add this?

[Val]

@OmerMalik I tried to mention android.support.test.runner.AndroidJUnitRunner in Run configuration but this didn't have an effect. Then I wrote it directly in build.gradle and it helped. It seems it should be set in defaultConfig to be visible.

[Omer Malik]

I read the android documentation and it is mentioned their, I missed the step, thank alot

[Del]

as a follow-up, one may see the message "Unable to find instrumentation info for". To fix that, tell the Android Studio launch configuration to use the specific test runner from the build.gradle file

[xyz]

For AndroidX, testInstrumentationRunner 'androidx.test.runner.AndroidJUnitRunner'

[huskygrad]

Hi, I have Dynamic Feature Modules in my app. For tests in the Feature Module, I'm using a custom testInstrumentationRunner , which is located in the app module. I'm getting this error "Test running failed: Instrumentation run failed due to 'Process crashed.'" Any idea how will it work across multiple modules? @Val

[Chenhe]

For AndroidX, use testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner" instead.