src/test/java/com/google/android/libraries/feed/sharedstream/scroll/PietScrollObserverTest.java

// Copyright 2019 The Feed Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package com.google.android.libraries.feed.sharedstream.scroll;

import static org.mockito.ArgumentMatchers.any;
import static org.mockito.ArgumentMatchers.eq;
import static org.mockito.ArgumentMatchers.same;
import static org.mockito.Mockito.verify;
import static org.mockito.Mockito.verifyZeroInteractions;
import static org.mockito.Mockito.when;
import static org.mockito.MockitoAnnotations.initMocks;

import android.app.Activity;
import android.support.v7.widget.RecyclerView;
import android.widget.FrameLayout;
import android.widget.LinearLayout;
import android.widget.LinearLayout.LayoutParams;
import com.google.android.libraries.feed.piet.FrameAdapter;
import com.google.android.libraries.feed.piet.host.ActionHandler;
import com.google.android.libraries.feed.piet.host.ActionHandler.ActionType;
import com.google.android.libraries.feed.piet.testing.FakeFrameAdapter;
import com.google.android.libraries.feed.sharedstream.publicapi.scroll.ScrollObservable;
import com.google.common.collect.ImmutableList;
import com.google.search.now.ui.piet.ActionsProto.Action;
import com.google.search.now.ui.piet.PietProto.Frame;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.Mock;
import org.robolectric.Robolectric;
import org.robolectric.RobolectricTestRunner;

/** Tests for {@link PietScrollObserverTest}. */
@RunWith(RobolectricTestRunner.class)
public class PietScrollObserverTest {

  @Mock private ScrollObservable scrollObservable;
  @Mock private ActionHandler actionHandler;

  // .newBuilder().build() creates a unique instance we can check same() against.
  private static final Action VIEW_ACTION = Action.newBuilder().build();

  private FrameAdapter frameAdapter;
  private FrameLayout viewport;
  private LinearLayout frameView;
  private PietScrollObserver pietScrollObserver;

  @Before
  public void setUp() {
    initMocks(this);
    Activity activity = Robolectric.setupActivity(Activity.class);
    viewport = new FrameLayout(activity);
    activity.getWindow().addContentView(viewport, new LayoutParams(100, 100));

    frameAdapter =
        FakeFrameAdapter.builder(activity)
            .setActionHandler(actionHandler)
            .addViewAction(VIEW_ACTION)
            .build();
    frameAdapter.bindModel(Frame.getDefaultInstance(), 0, null, ImmutableList.of());
    frameView = frameAdapter.getFrameContainer();

    pietScrollObserver = new PietScrollObserver(frameAdapter, viewport, scrollObservable);
  }

  @Test
  public void testTriggersActionsWhenIdle() {
    pietScrollObserver.onScrollStateChanged(viewport, "", RecyclerView.SCROLL_STATE_IDLE, 123L);

    verify(actionHandler)
        .handleAction(
            same(VIEW_ACTION),
            eq(ActionType.VIEW),
            eq(Frame.getDefaultInstance()),
            eq(frameAdapter.getFrameContainer()),
            any() /* LogData */);
  }

  @Test
  public void testDoesNotTriggerWhenScrolling() {
    pietScrollObserver.onScrollStateChanged(viewport, "", RecyclerView.SCROLL_STATE_DRAGGING, 123L);

    verifyZeroInteractions(actionHandler);
  }

  @Test
  public void testTriggersOnFirstDraw() {
    pietScrollObserver.installFirstDrawTrigger();
    when(scrollObservable.getCurrentScrollState()).thenReturn(RecyclerView.SCROLL_STATE_IDLE);

    frameView.getViewTreeObserver().dispatchOnGlobalLayout();

    verify(actionHandler)
        .handleAction(
            same(VIEW_ACTION),
            eq(ActionType.VIEW),
            eq(Frame.getDefaultInstance()),
            eq(frameView),
            any() /* LogData */);
  }

  @Test
  public void testDoesNotTriggerOnSecondDraw() {
    pietScrollObserver.installFirstDrawTrigger();
    when(scrollObservable.getCurrentScrollState()).thenReturn(RecyclerView.SCROLL_STATE_DRAGGING);

    // trigger on global layout - actions will not trigger because scrolling is not IDLE
    frameView.getViewTreeObserver().dispatchOnGlobalLayout();

    when(scrollObservable.getCurrentScrollState()).thenReturn(RecyclerView.SCROLL_STATE_IDLE);

    // trigger on global layout - actions will not trigger because observer has been removed.
    frameView.getViewTreeObserver().dispatchOnGlobalLayout();

    verifyZeroInteractions(actionHandler);
  }

  @Test
  public void testTriggersOnAttach() {
    // Actions will not fire before attached to window
    frameView.getViewTreeObserver().dispatchOnGlobalLayout();
    verifyZeroInteractions(actionHandler);

    // Now attach to window and actions should fire
    viewport.addView(frameView);
    frameView.getViewTreeObserver().dispatchOnGlobalLayout();
    verify(actionHandler)
        .handleAction(
            same(VIEW_ACTION),
            eq(ActionType.VIEW),
            eq(Frame.getDefaultInstance()),
            eq(frameView),
            any() /* LogData */);
  }
}