VrShell: Add test for fullscreen transitions.

chrome/browser/android/vr_shell/ui_scene_manager_unittest.cc

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/android/vr_shell/ui_scene_manager.h"
 
 #include "base/macros.h"
+#include "chrome/browser/android/vr_shell/ui_elements/ui_element.h"
 #include "chrome/browser/android/vr_shell/ui_scene.h"
 #include "chrome/browser/android/vr_shell/vr_browser_interface.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 using testing::InSequence;
 
 namespace vr_shell {
 
 namespace {
@@ skipping 53 matching lines @@
   EXPECT_CALL(*browser_, OnContentPaused(true)).Times(1);
   manager_->OnAppButtonClicked();
   EXPECT_FALSE(scene_->GetWebVrRenderingEnabled());
 
   // Clicking it again should resume content rendering.
   EXPECT_CALL(*browser_, OnContentPaused(false)).Times(1);
   manager_->OnAppButtonClicked();
   EXPECT_TRUE(scene_->GetWebVrRenderingEnabled());
 }
 
+TEST_F(UiSceneManagerTest, UiUpdatesForFullscreen) {
+  InSequence s;

[cjgrant, 2017/05/10 02:45:00]

Not needed - it's only required to ensure that mock calls are seen in order.

[amp, 2017/05/10 16:05:55]

Done.

+  // Set mode to not WebVR, everything should be visible.
+  manager_->SetWebVrMode(false);
+
+  // Hold onto the background color to make sure it changes.
+  vr::Colorf initialBackground = scene_->GetBackgroundColor();
+
+  for (UiElement* element : manager_->browser_ui_elements_) {

[cjgrant, 2017/05/10 02:45:00]

browser_ui_elements_ is an internal convenience that I don't think a test should
depend on.  What about inspecting the scene instead? It already exposes the set
of elements, so maybe you can check that all elements that aren't fill NONE or
CONTENT are hidden?

Alternatively, we had previously attached descriptive strings to elements, but
removed them to keep them out of the binary.  What if we made an enum of
elements instead, assigning values to elements that tests care about?  Then
tests can identify elements in cases like this.  Thoughts?

[amp, 2017/05/10 16:05:55]

Thanks for the suggestion.  I had tried this at first, but the only method I saw
then was the GetWorldElements method which does a check on calculated opacity
and didn't return anything so I gave up and went the internal route.  After
reading your comment I went back and checked and realized that there was
GetUiElements that returns all of them.  Your suggestion of checking the fill
type sounds like it should work.
We might end up going that route eventually, but I think I can make it work with
just checking the fill types for now (as the CONTENT type is the main one I care
about).  Once we start checking for other things we may need to have add some
mapping via enum's etc.

+    EXPECT_TRUE(element->visible());
+  }
+
+  manager_->SetFullscreen(true);
+
+  // All elements should be hidden except for main content.
+  for (UiElement* element : manager_->browser_ui_elements_) {
+    if (element == manager_->main_content_) {
+      EXPECT_TRUE(element->visible());
+      continue;
+    }
+    EXPECT_FALSE(element->visible());
+  }
+  // Make sure background has changed for fullscreen.
+  EXPECT_NE(initialBackground.r, scene_->GetBackgroundColor().r);
+  EXPECT_NE(initialBackground.g, scene_->GetBackgroundColor().g);
+  EXPECT_NE(initialBackground.b, scene_->GetBackgroundColor().b);
+  // Alpha doesn't change
+
+  manager_->SetFullscreen(false);
+
+  // Everything should return to original state after leaving fullscreen.
+  for (UiElement* element : manager_->browser_ui_elements_) {
+    EXPECT_TRUE(element->visible());
+  }
+  EXPECT_EQ(initialBackground.r, scene_->GetBackgroundColor().r);
+  EXPECT_EQ(initialBackground.g, scene_->GetBackgroundColor().g);
+  EXPECT_EQ(initialBackground.b, scene_->GetBackgroundColor().b);
+  EXPECT_EQ(initialBackground.a, scene_->GetBackgroundColor().a);
+}
+
 }  // namespace vr_shell