Espresso - Validate TextView contents Android

Issue

I am trying to write a Expresso Test on Android to validate the TextView content. When I read the text from resources as below it works

    @Test
    public void changeText_newActivity() {
        onView(withId(R.id.mainContent)).check(matches(withText("Hello World!")));
}

The above is the test using espresso Below is the code on android activity where it works

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/mainContent"
    android:text="@string/hello_world"
    />

But When I replace the text using hardcoded text instead of referencing to the resources the test fails and getting the error unable to find the view in the view hierarchy

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/mainContent"
    android:text="Hello world!"
    />

Below is the error when I run the test

android.support.test.espresso.NoMatchingViewException: No views in hierarchy found matching: with text: is "Hello world!"

Appreciated your help in advance.

Solution

Code    "Hello world!"
               ^
Test    "Hello World!"

See the difference? W and w are not the same.

Espresso rightfully cannot find such a view, because there is none mathing.

Answered By - azizbekian