chromeos: Add support for dimming the screen.

ash/wm/screen_dimmer_unittest.cc

Index: ash/wm/screen_dimmer_unittest.cc
diff --git a/ash/wm/screen_dimmer_unittest.cc b/ash/wm/screen_dimmer_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..b66cd2f9afd72f65d632d7082c789b9b96d9a102
--- /dev/null
+++ b/ash/wm/screen_dimmer_unittest.cc
@@ -0,0 +1,78 @@
+// Copyright (c) 2012 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 "ash/wm/screen_dimmer.h"
+
+#include "ash/shell.h"
+#include "ash/test/ash_test_base.h"
+#include "base/basictypes.h"
+#include "base/memory/scoped_ptr.h"
+#include "ui/aura/root_window.h"
+#include "ui/gfx/compositor/layer.h"
+
+namespace ash {
+namespace test {
+
+class ScreenDimmerTest : public AshTestBase {
+ public:
+  ScreenDimmerTest() : dimmer_(NULL) {}
+  virtual ~ScreenDimmerTest() {}
+
+  void SetUp() OVERRIDE {
+    AshTestBase::SetUp();
+    dimmer_ = Shell::GetInstance()->screen_dimmer();
+    test_api_.reset(new internal::ScreenDimmer::TestApi(dimmer_));
+  }
+
+ protected:
+  internal::ScreenDimmer* dimmer_;  // not owned
+
+  scoped_ptr<internal::ScreenDimmer::TestApi> test_api_;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(ScreenDimmerTest);
+};
+
+TEST_F(ScreenDimmerTest, DimAndUndim) {
+  // Don't create a layer until we need to.
+  EXPECT_TRUE(test_api_->layer() == NULL);
+  dimmer_->SetDimming(false);
+  EXPECT_TRUE(test_api_->layer() == NULL);
+
+  // When we enable dimming, the layer should be created and stacked at the top
+  // of the root's children.
+  dimmer_->SetDimming(true);
+  ASSERT_TRUE(test_api_->layer() != NULL);
+  ui::Layer* root_layer = Shell::GetInstance()->GetRootWindow()->layer();
+  ASSERT_TRUE(!root_layer->children().empty());
+  EXPECT_EQ(test_api_->layer(), root_layer->children().back());
+  EXPECT_TRUE(test_api_->layer()->visible());
+  EXPECT_GT(test_api_->layer()->GetTargetOpacity(), 0.0f);
+
+  // When we disable dimming, the layer should be animated back to full
+  // transparency.
+  dimmer_->SetDimming(false);
+  ASSERT_TRUE(test_api_->layer() != NULL);
+  EXPECT_TRUE(test_api_->layer()->visible());
+  EXPECT_FLOAT_EQ(0.0f, test_api_->layer()->GetTargetOpacity());
+}
+
+TEST_F(ScreenDimmerTest, ResizeLayer) {
+  // The dimming layer should be initially sized to cover the root window.
+  dimmer_->SetDimming(true);
+  ui::Layer* dimming_layer = test_api_->layer();
+  ASSERT_TRUE(dimming_layer != NULL);
+  ui::Layer* root_layer = Shell::GetInstance()->GetRootWindow()->layer();
+  EXPECT_EQ(gfx::Rect(root_layer->bounds().size()).ToString(),
+            dimming_layer->bounds().ToString());
+
+  // When we resize the root window, the dimming layer should be resized to
+  // match.
+  gfx::Size kNewSize(400, 300);
+  Shell::GetInstance()->GetRootWindow()->SetHostSize(kNewSize);
+  EXPECT_EQ(kNewSize.ToString(), dimming_layer->bounds().size().ToString());
+}
+
+}  // namespace test
+}  // namespace ash