Best way to run Robolectric tests on Android device

Question

I have a Robolectric test project setup, but I'd like to also run these tests on my device to check that I don't get bit by JVM vs Dalvik implementation differences.

Unlike robolectric tests, I won't run these tests frequently. My concern is that there's little effort to maintain the test suite and that they verify actual device functionality.

What's the best way to do that?

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What I've currently got:

My robolectric test project as a test case TestPackage. I created an Android Test project with a test case TestRoboOnAndroid. It creates a TestPackage and has a test for each test in TestPackage.

Right now, every time I add a test to my robolectric suite, I need to manually add it to my device suite. Is there some way to do that automatically with reflection?

Also, Robolectric uses JUnit 4 (by default) and Android uses JUnit 3. So I have to write all of my Robolectric tests using JUnit 3 style (importing from junit.framework instead of org.junit).

Answer 1

The whole point of Robolectric is NOT to run it on the device and the design is based on that. If you want to run something on the device look at the default instrumentation tests from the SDK or Robotium.

It is totally feasible to run your Robolectric tests on the JVM and in addition create Robotium tests that rely on device specific interaction (e.g. creating screenshots, hardware differences...) and run on devices and emulators all combined into one build.

The easiest way to do that is to use the Android Maven Plugin.

Answer 2

I use a tiered system, where I prefer earlier tiers where possible:

• Pure unit tests. I try to make as much code as possible fully independent of Android APIs, and then use "pure" unit tests which can run on any JVM. These tests are the fastest, and it helps keep code that has no need to be Android-specific portable.

• Robolectric-supported unit tests. Where my code has only small dependencies on Android APIs, that can be satisfied by Robolectric shadows, I test it with Robolectric. There is a little more setup time for Robolectric compared to pure tests, but it's still faster than starting/running on an emulator.

• Android framework tests. Where Robolectric doesn't cut it - either because the shadows don't exist, or because I'm heavily using Android APIs (and therefore want to test against the Real Thing) - I write test that run on the emulator/device with the default framework.

The point of the tiers is to keep things as simple as possible, which keeps the full suite faster and helps promote cleaner code.