Where is log output written to when using Robolectric + Roboguice?

Question

I\'m using Robolectric to test Android. I\'m running my tests via maven, e.g.

mvn -Dtest=LogTest test

If I have code that writes to the logs,

Answer 1

The solution that worked out best for me (or at all) was to initialize a replacement injected implementation (during testing only) of RoboGuice's Ln.Print class to do System.out printing instead of Android's Log printing, given I was actually using Robolectric to avoid having to depend on the Android subsystem to run my tests in the first place.

From Ln.java:

public class Ln  {
...

/**
 * print is initially set to Print(), then replaced by guice during
 * static injection pass.  This allows overriding where the log message is delivered to.
 */
@Inject protected static Print print = new Print();

So basically:

public class TestModule extends AbstractModule {

    @Override
    protected void configure() {
        bind(Ln.Print.class).to(TestLogPrint.class);
    }

}

and:

public class TestLogPrint extends Print {

    public int println(int priority, String msg ) {

        System.out.println(
            String.format(
                "%s%s", 
                getScope(4), 
                msg
            )
        );

        return 0;
    }

    protected static String getScope(int skipDepth) {
        final StackTraceElement trace = Thread.currentThread().getStackTrace()[skipDepth];
        return String.format("%s | %s.%s | ", new Date(), trace.getFileName().replace(".java", ""), trace.getMethodName());
    }
}

That of course assuming the standard Robolectric init to hook the module up with RoboGuice:

@Before
public void setUp() throws Exception {

    Module roboGuiceModule = RoboGuice.newDefaultRoboModule(Robolectric.application);
    Module productionModule = Modules.override(roboGuiceModule).with(new CustomRoboModule());
    Module testModule = Modules.override(productionModule).with(new TestModule());

    RoboGuice.setBaseApplicationInjector(Robolectric.application, RoboGuice.DEFAULT_STAGE, testModule);
    RoboGuice.injectMembers(Robolectric.application, this);

}