RecyclerView testing - Using assert item count of RecyclerView adapter

RecyclerViewItemCountAssertion.kt

import android.view.View
import androidx.recyclerview.widget.RecyclerView
import androidx.test.espresso.NoMatchingViewException
import androidx.test.espresso.ViewAssertion
import androidx.test.espresso.matcher.ViewMatchers.assertThat
import org.hamcrest.Matcher
import org.hamcrest.Matchers.`is`

/**
 * Using assert item count of RecyclerView adapter
 */
class RecyclerViewItemCountAssertion private constructor(
    private val matcher: Matcher<Int>
) : ViewAssertion {

    override fun check(view: View?, noViewFoundException: NoMatchingViewException?) {
        if (noViewFoundException != null) {
            throw noViewFoundException
        }
        val recyclerView: RecyclerView? = view as? RecyclerView
        val adapter = recyclerView?.adapter
        assertThat(adapter?.itemCount, matcher)
    }

    companion object {

        fun withItemCount(expectedCount: Int): RecyclerViewItemCountAssertion {
            return withItemCount(`is`(expectedCount))
        }

        fun withItemCount(matcher: Matcher<Int>): RecyclerViewItemCountAssertion {
            return RecyclerViewItemCountAssertion(matcher)
        }
    }
}