Is it possible to find out if an Android application runs as part of an instrumentation test

Question

Is there a runtime check for an application to find out if it runs as part of an instrumentation test?

Background: Our application performs a database sync when star

Answer 1

This work for me because no actual device is running

public static boolean isUnitTest() {
    return Build.BRAND.startsWith(Build.UNKNOWN) && Build.DEVICE.startsWith(Build.UNKNOWN) && Build.DEVICE.startsWith(Build.UNKNOWN) && Build.PRODUCT.startsWith(Build.UNKNOWN);
}

Answer 2

You can try this

if (isRunningTest == null) {
        isRunningTest = false;
        StackTraceElement[] stackTrace = Thread.currentThread().getStackTrace();
        List<StackTraceElement> list = Arrays.asList(stackTrace);
        for (StackTraceElement element : list) {
            if (element.getClassName().startsWith("androidx.test.runner.MonitoringInstrumentation")) {
                isRunningTest = true;
                break;
            }
        }
    }

Answer 3

Since API Level 29, the static ActivityManager.isRunningInUserTestHarness() method is available.

But for API below 29:

Developers can add their own custom property:

subprojects {
    tasks.withType(Test).all {
        systemProperty "is-test-run", "true"
    }
}

which then needs to be checked somehow:

public static boolean isTestRun() {
     return "true".equals(System.getProperty("is-test-run", "false"));
}

Answer 4

If you are using Robolectric, you can do something like this:

public boolean isUnitTest() {
        String device = Build.DEVICE;
        String product = Build.PRODUCT;
        if (device == null) {
            device = "";
        }

        if (product == null) {
            product = "";
        }
        return device.equals("robolectric") && product.equals("robolectric");
    }

Answer 5

Since API Level 11, the ActivityManager.isRunningInTestHarness() method is available. This might do what you want.

Answer 6

A much simpler solution is check for a class that would only be present in a test classpath, works with JUnit 4 (unlike the solution using ActivityUnitTestCase) and doesn't require to send custom intents to your Activities / Services (which might not even be possible in some cases)

private boolean isTesting() {
    try {
        Class.forName("com.company.SomeTestClass");
        return true;
    } catch (ClassNotFoundException e) {
        return false;
    }
}