Unit Test for WebView animating in and out of screen

android_webview/browser/browser_view_renderer_unittest.cc

Index: android_webview/browser/browser_view_renderer_unittest.cc
diff --git a/android_webview/browser/browser_view_renderer_unittest.cc b/android_webview/browser/browser_view_renderer_unittest.cc
index b4a9d42227241cef82d61d71a47608eb57d52001..04c7d6b9e3651080dfe0168f5cf19ae1445ae638 100644
--- a/android_webview/browser/browser_view_renderer_unittest.cc
+++ b/android_webview/browser/browser_view_renderer_unittest.cc
@@ -59,4 +59,80 @@ class ClearViewTest : public RenderingTest {
 
 RENDERING_TEST_F(ClearViewTest);
 
+// - The first ondraw is onscreen. It reads the default draw constraints. The
+//   first DrawGL will post the new constraints to UI thread.
+// - The second onDraw is offscreen with an empty global visible rect. It reads
+//   the new draw constraints. The second DrawGL will be skipped because the
+//   WebView is offscreen.
+// - The third onDraw is the result of force invalidate from the second onDraw.
+//   It reads the same draw constraints as the second onDraw does.
+class TestAnimateInAndOutOfScreen : public RenderingTest {
+ public:
+  TestAnimateInAndOutOfScreen()
+      : on_draw_count_(0u), draw_constraints_updated_count_(0u) {
+    new_transform_.Scale(2.0, 2.0);
+  }
+
+  void StartTest() override {
+    browser_view_renderer_->SetContinuousInvalidate(true);
+  }
+
+  void WillOnDraw() override {
+    on_draw_count_++;
+    if (on_draw_count_ == 2u) {
+      browser_view_renderer_->PrepareToDraw(gfx::Vector2d(), gfx::Rect());
+      browser_view_renderer_->SetContinuousInvalidate(false);
+    }
+  }
+
+  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 (draw_constraints_updated_count_ == 1u)
+      transform = new_transform_;
+
+    transform.matrix().asColMajorf(draw_info.transform);
+    return true;
+  }
+
+  void ParentDrawConstraintsUpdated() override {
+    draw_constraints_updated_count_++;
+    ParentCompositorDrawConstraints initial_constraints;
+    ParentCompositorDrawConstraints new_constraints(
+        false, new_transform_, gfx::Rect(window_->surface_size()));
+    if (draw_constraints_updated_count_ == 1u) {
+      EXPECT_TRUE(initial_constraints.Equals(
+          browser_view_renderer_->parent_draw_constraints_for_testing()));
+    }
+
+    if (draw_constraints_updated_count_ == 2u) {
+      EXPECT_TRUE(new_constraints.Equals(
+          browser_view_renderer_->parent_draw_constraints_for_testing()));
+    }
+    if (draw_constraints_updated_count_ == 3u) {
+      EXPECT_TRUE(new_constraints.Equals(
+          browser_view_renderer_->parent_draw_constraints_for_testing()));
+      EndTest();
+    }
+    // Add test to assert the next time parent draw constraints will be the
+    // initial constraints.
+  }
+
+ private:
+  size_t on_draw_count_;
+  size_t draw_constraints_updated_count_;
+  gfx::Transform new_transform_;
+};
+
+RENDERING_TEST_F(TestAnimateInAndOutOfScreen);
+
 }  // namespace android_webview