NestedScrollViewScrollToAction because regular ScrollTo doesn't work

NestedScrollViewScrollToAction.java

package com.example.NestedScrollViewScrollToAction;

import android.graphics.Rect;
import android.support.design.widget.CoordinatorLayout;
import android.support.test.espresso.PerformException;
import android.support.test.espresso.UiController;
import android.support.test.espresso.ViewAction;
import android.support.test.espresso.matcher.ViewMatchers.Visibility;
import android.support.test.espresso.util.HumanReadables;
import android.support.v4.widget.NestedScrollView;
import android.util.Log;
import android.view.View;

import org.hamcrest.Matcher;

import static android.support.test.espresso.matcher.ViewMatchers.isAssignableFrom;
import static android.support.test.espresso.matcher.ViewMatchers.isDescendantOfA;
import static android.support.test.espresso.matcher.ViewMatchers.isDisplayingAtLeast;
import static android.support.test.espresso.matcher.ViewMatchers.withEffectiveVisibility;
import static org.hamcrest.Matchers.allOf;
import static org.hamcrest.Matchers.anyOf;

/**
 * Enables scrolling to the given view. View must be a descendant of a ScrollView.
 */
public final class NestedScrollViewScrollToAction implements ViewAction {

    private static final String TAG = NestedScrollViewScrollToAction.class.getSimpleName();

    public static NestedScrollViewScrollToAction scrollTo() {
        return new NestedScrollViewScrollToAction();
    }

    @SuppressWarnings("unchecked")
    @Override
    public Matcher<View> getConstraints() {
        return allOf(withEffectiveVisibility(Visibility.VISIBLE), isDescendantOfA(anyOf(
                isAssignableFrom(NestedScrollView.class))));
    }

    @Override
    public void perform(UiController uiController, View view) {
        if (isDisplayingAtLeast(90).matches(view)) {
            Log.i(TAG, "View is already displayed. Returning.");
            return;
        }

        View parentScrollView = findScrollView(view);

        CoordinatorLayout.LayoutParams params = (CoordinatorLayout.LayoutParams) parentScrollView.getLayoutParams();
        params.setBehavior(null);
        parentScrollView.requestLayout();

        uiController.loopMainThreadUntilIdle();

        Rect rect = new Rect();
        view.getDrawingRect(rect);
        if (!view.requestRectangleOnScreen(rect, true /* immediate */)) {
            Log.w(TAG, "Scrolling to view was requested, but none of the parents scrolled.");
        }

        uiController.loopMainThreadUntilIdle();

        if (!isDisplayingAtLeast(90).matches(view)) {
            throw new PerformException.Builder()
                    .withActionDescription(this.getDescription())
                    .withViewDescription(HumanReadables.describe(view))
                    .withCause(new RuntimeException(
                            "Scrolling to view was attempted, but the view is not displayed"))
                    .build();
        }
    }

    private View findScrollView(View view) {
        View parent = (View) view.getParent();
        if (parent != null) {
            if (parent instanceof NestedScrollView) {
                return parent;
            }
            return findScrollView(parent);
        }
        throw new PerformException.Builder()
                .withActionDescription(this.getDescription())
                .withViewDescription(HumanReadables.describe(view))
                .withCause(new RuntimeException(
                        "Scrolling aborted due to not being NestedScrollView child"))
                .build();
    }

    @Override
    public String getDescription() {
        return "scroll to";
    }
}

I hacked in some code to make it work if the NestedScrollView was inside a ViewPager

    // Find parent view that has CoordinatorLayout.LayoutParams -Matt
    View view2 = parentScrollView;
    while(true) {
        if(view2.getLayoutParams() instanceof CoordinatorLayout.LayoutParams) {
            CoordinatorLayout.LayoutParams params = (CoordinatorLayout.LayoutParams) view2.getLayoutParams();
            params.setBehavior(null);
            break;
        }
        view2 = (View) view2.getParent();
    }

// CoordinatorLayout.LayoutParams params = (CoordinatorLayout.LayoutParams) parentScrollView.getLayoutParams();
// params.setBehavior(null);
parentScrollView.requestLayout();