Unit Test for WebView animating in and out of screen

android_webview/browser/browser_view_renderer_unittest.cc

 // Copyright 2014 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 "android_webview/browser/browser_view_renderer.h"
 #include "android_webview/browser/test/rendering_test.h"
 
 namespace android_webview {
 
 class SmokeTest : public RenderingTest {
@@ skipping 41 matching lines @@
 
   void DidDrawOnRT(SharedRendererState* functor) override {
     EndTest();
   }
  private:
   size_t on_draw_count_;
 };
 
 RENDERING_TEST_F(ClearViewTest);
 
+class TestAnimateInAndOutOfScreen : public RenderingTest {
+ public:
+  TestAnimateInAndOutOfScreen() : step_(1u) {}

[boliu, 2015/03/19 00:15:20]

We are computer scientists!! We start counting from 0!

Also you can put it in StartTest.

[hush (inactive), 2015/03/19 01:02:51]

Done. But I can't put it in StartTest because the constructor needs to assign a
value to it..

+
+  void StartTest() override {
+    new_constraints_ = ParentCompositorDrawConstraints(
+        false, gfx::Transform(), gfx::Rect(window_->surface_size()));
+    new_constraints_.transform.Scale(2.0, 2.0);
+    browser_view_renderer_->SetContinuousInvalidate(true);
+  }
+
+  void WillOnDraw() override {
+    if (step_ == 1u) {
+      // Step 1: A single onDraw on screen. The parent draw constraints
+      // of the BVR will updated to be the initial constraints.
+      browser_view_renderer_->SetContinuousInvalidate(false);
+    }
+    if (step_ == 2u) {
+      // Step 2: A single onDrraw off screen. The parent draw constraints of the
+      // BVR will be updated to the new constraints.
+      browser_view_renderer_->PrepareToDraw(gfx::Vector2d(), gfx::Rect());
+    }
+    if (step_ == 3u) {
+      // Step 3: Continuously call onDraw onscreen. End the test when the parent
+      // draw constraints of BVR is updated to initial constraints.
+      browser_view_renderer_->SetContinuousInvalidate(true);
+    }
+  }
+
+  void DidOnDraw(bool success) override { EXPECT_TRUE(success); }
+
+  bool WillDrawOnRT(SharedRendererState* functor,
+                    AwDrawGLInfo& draw_info) override {
+    if (browser_view_renderer_->global_visible_rect_for_testing().IsEmpty())
+      return false;
+
+    draw_info.width = window_->surface_size().width();
+    draw_info.height = window_->surface_size().height();
+    draw_info.is_layer = false;
+
+    gfx::Transform transform;
+    if (step_ == 2u)
+      transform = new_constraints_.transform;
+
+    transform.matrix().asColMajorf(draw_info.transform);
+    return true;
+  }
+
+  void ParentDrawConstraintsUpdated() override {
+    ParentCompositorDrawConstraints constraints =
+        browser_view_renderer_->parent_draw_constraints_for_testing();

[boliu, 2015/03/19 00:15:20]

We don't need both ConstraintsUpdated and GetConstraints. Just put the
constraints as a parameter to the client call?

[hush (inactive), 2015/03/19 01:02:51]

Done.

+    if (step_ == 1u && constraints.Equals(initial_constraints_)) {
+      step_++;

[boliu, 2015/03/19 00:15:20]

Do we get more than one ParentDrawConstraintsUpdated here? ie do we need the
constraints check here and below? Shouldn't we be validating those constraints?

[hush (inactive), 2015/03/19 01:02:51]

By 'validating' I guess you mean EXPECT_TRUE?
I'm doing Equals check instead of EXPECT_TRUE because the constraints may not be
immediately updated. There will be multiple ParentDrawConstraintsUpdated
callbacks until the constraints are updated to |new_constraints_|. So I'm only
advancing the steps when the constraints are what they should be.

[boliu, 2015/03/19 01:05:33]

I don't understand why there will be multiple ParentDrawConstraintsUpdated calls
though

+    }
+
+    if (step_ == 2u && constraints.Equals(new_constraints_)) {
+      step_++;
+      PostInvalidate();
+    }
+
+    if (step_ == 3u && constraints.Equals(initial_constraints_)) {
+      step_++;
+      browser_view_renderer_->SetContinuousInvalidate(false);
+      EndTest();
+    }
+  }
+
+ private:
+  size_t step_;
+  ParentCompositorDrawConstraints initial_constraints_;
+  ParentCompositorDrawConstraints new_constraints_;
+};
+
+RENDERING_TEST_F(TestAnimateInAndOutOfScreen);
+
 }  // namespace android_webview