Android Studio Unit Testing: unable to find instrumentation OR class not found ex

Question

I have a test suite within my Android studio that has the following dir structure:

-MainProject
 -src
  --com
  --tests
    --java.xx.xxx.xx.test

Within my AndroidManifest, I have the following:

<instrumentation
    android:name="android.test.InstrumentationTestRunner"
    android:targetPackage="tests.java.xxx.xxx.xxx.test" />

When I run my tests from the command line using: ./gradlew connectedInstrumentTest, I simply get:

Tests on Nexus 5 - 4.4.2 failed: Instrumentation run failed due to 'java.lang.ClassNotFoundException'

When I run the tests from inside Android Studio I get:

Running tests
Test running startedTest running failed: Unable to find instrumentation info for: ComponentInfo{tests.xxx.xxx.xxx.xxx.test/android.test.InstrumentationTestRunner}
Empty test suite.

I also have the testPackageName specified in my defaultConfig in the build.gradle file. Am running Android Studio 0.4.6 on Ubuntu 12.0.4.

Any ideas?

Answer 1

I had the same problem and could not find anything on the net. The answer was pretty simple: You have to edit the RunConfiguration of your test so that it is not a Android Test but a JUnit test.

So basically I did the following:

1. Clicked "Edit Configuration"
2. Clicked "Add new Configuration" and chose JUnit
3. Inserted a name and the and chose "All in package" at Test kind.

That's it.

Answer 2

I also get error like this and I added the following line in build.gradle file as shown in https://google.github.io/android-testing-support-library/docs/espresso/setup/index.html and it's working. I hope it will also help you :-)

testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"