How To do code coverage with emma during Android Unit Tests

Question

First of all i assume that you have already a project and a test project with test cases. Also you have installed the Android sdk. The android testing framework has already a built-in ability to generate a code coverage report about your tests. This built-in ability is based on emma.

Firs of all you've to create a build.xml for your project, which should be tested:

android update project --path <Path to your Project>

Next step is to create the build.xml for the test project (where the test cases are located):

android update test-project -m <Path to your Project> -p <Path to your Testproject>

In the next step you ccan run the coverage. Therefor you must switch into you Testproject:

cd <Path to your Testproject>
ant emma debug install test

This will build, instrument, deploy and run your unit tests. It will also generate a HTML coverage report. The location of the report will be displayed in the last few lines of the Ant script’s output.

For more Details: http://developer.android.com/tools/building/building-cmdline.html#AntReference

Troubleshooting:

If your OS doesn't know the commands you have to add some paths to the environment path variable of you OS: you have to add the Path of the android.bat (normally /tools) and the path of the ant.bat (depending where you installed Ant; If you use Eclipse with ADT it is normally there: /plugins/org.apache.ant.../bin)
If you're using SDK 13 or older you've to use ant coverage instead of ant emma debug install test
The tests are running completely but there is no report (and there is also a "failed"-message which contains "permission denied"): You need to use a rooted device or an emulator
Generally it could help to clean your projects when you get a "BUILD FAILED"
If you have libraries that you use and you get an error. Make sure you put them into a "libs" directory. ant automatically adds the libraries in "libs" to the build path.