How can you check a TextinputLayout's error with Espresso

Issue

I want to be able to run a matcher against a TextInputLayout view that has an error set.

onView(withId(R.id.myTextInputLayout)).check(matches(withText('myError')));

withTest() does not seem to work with the TextInputLayout error message. Does any else know how to do this?

Thank you for your help.

Solution

Implement a custom ViewMatcher to test views that are not supported out of the box.

Here is an example implementation of withError matcher for TextInputLayout

 public static Matcher<View> withErrorInInputLayout(final Matcher<String> stringMatcher) {
    checkNotNull(stringMatcher);

    return new BoundedMatcher<View, TextInputLayout>(TextInputLayout.class) {
        String actualError = "";

        @Override
        public void describeTo(Description description) {
            description.appendText("with error: ");
            stringMatcher.describeTo(description);
            description.appendText("But got: " + actualText);
        }

        @Override
        public boolean matchesSafely(TextInputLayout textInputLayout) {
            CharSequence error = textInputLayout.getError();
            if (error != null) {
                actualError = error.toString();
                return stringMatcher.matches(actualError);
            }
            return false;
        }
    };
}

public static Matcher<View> withErrorInInputLayout(final String string) {
    return withErrorInInputLayout(is(string));
}

Answered By - Be_Negative