Experimental app list: "All apps" button has a folder-like icon.

ui/app_list/folder_image_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 "ui/app_list/folder_image.h"
+
+#include "testing/gtest/include/gtest/gtest.h"
+#include "third_party/skia/include/core/SkBitmap.h"
+#include "third_party/skia/include/core/SkColor.h"
+#include "ui/app_list/app_list_constants.h"
+#include "ui/app_list/app_list_item.h"
+#include "ui/app_list/app_list_item_list.h"
+#include "ui/app_list/app_list_model.h"
+#include "ui/gfx/skia_util.h"
+
+namespace app_list {
+
+namespace {
+
+gfx::ImageSkia CreateSquareBitmapWithColor(int size, SkColor color) {
+  SkBitmap bitmap;
+  bitmap.allocN32Pixels(size, size);
+  bitmap.eraseColor(color);
+  return gfx::ImageSkia::CreateFrom1xBitmap(bitmap);
+}
+
+bool ImagesAreEqual(const gfx::ImageSkia& image1,
+                    const gfx::ImageSkia& image2) {
+  return gfx::BitmapsAreEqual(*image1.bitmap(), *image2.bitmap());
+}
+
+// Listens for OnFolderImageUpdated and sets a flag upon receiving the signal.
+class TestFolderImageObserver : public FolderImageObserver {
+ public:
+  TestFolderImageObserver() : updated_flag_(false) {}
+
+  bool updated() const { return updated_flag_; }
+
+  void Reset() { updated_flag_ = false; }
+
+  // FolderImageObserver overrides:
+  void OnFolderImageUpdated() override { updated_flag_ = true; }
+
+ private:
+  bool updated_flag_;
+};
+
+}  // namespace
+
+class FolderImageTest : public testing::Test {
+ public:
+  FolderImageTest() : folder_image_(app_list_model_.top_level_item_list()) {}
+
+  ~FolderImageTest() {}
+
+  void SetUp() {
+    // Populate the AppListModel with three items (to test that the FolderImage
+    // correctly supports having fewer than four icons).
+    AddAppWithColoredIcon("app1", SK_ColorRED);
+    AddAppWithColoredIcon("app2", SK_ColorGREEN);
+    AddAppWithColoredIcon("app3", SK_ColorBLUE);
+
+    observer_.Reset();
+    folder_image_.AddObserver(&observer_);
+  }
+
+  void TearDown() { folder_image_.RemoveObserver(&observer_); }
+
+ protected:
+  void AddAppWithColoredIcon(const std::string& id, SkColor icon_color) {
+    scoped_ptr<AppListItem> item(new AppListItem(id));
+    item->SetIcon(CreateSquareBitmapWithColor(kListIconSize, icon_color),
+                  false);
+    app_list_model_.AddItem(item.Pass());
+  }
+
+  AppListModel app_list_model_;
+
+  FolderImage folder_image_;
+
+  TestFolderImageObserver observer_;
+};
+
+TEST_F(FolderImageTest, UpdateListTest) {
+  gfx::ImageSkia icon1 = folder_image_.icon();
+
+  // Call UpdateIcon and ensure that the observer event fired.
+  folder_image_.UpdateIcon();
+  EXPECT_TRUE(observer_.updated());
+  observer_.Reset();
+  // The icon should not have changed.
+  EXPECT_TRUE(ImagesAreEqual(icon1, folder_image_.icon()));
+
+  // Swap two items. Ensure that the observer fired and the icon changed.
+  app_list_model_.top_level_item_list()->MoveItem(2, 1);
+  EXPECT_TRUE(observer_.updated());
+  observer_.Reset();
+  gfx::ImageSkia icon2 = folder_image_.icon();
+  EXPECT_FALSE(ImagesAreEqual(icon1, icon2));
+
+  // Swap back items. Ensure that the observer fired and the icon changed back.
+  app_list_model_.top_level_item_list()->MoveItem(2, 1);
+  EXPECT_TRUE(observer_.updated());
+  observer_.Reset();
+  EXPECT_TRUE(ImagesAreEqual(icon1, folder_image_.icon()));
+
+  // Add a new item. Ensure that the observer fired and the icon changed.
+  AddAppWithColoredIcon("app4", SK_ColorYELLOW);
+  EXPECT_TRUE(observer_.updated());
+  observer_.Reset();
+  gfx::ImageSkia icon3 = folder_image_.icon();
+  EXPECT_FALSE(ImagesAreEqual(icon1, icon3));
+
+  // Add a new item. The observer should not fire, nor should the icon change
+  // (because it does not affect the first four icons).
+  AddAppWithColoredIcon("app5", SK_ColorCYAN);
+  EXPECT_FALSE(observer_.updated());
+  observer_.Reset();
+  EXPECT_TRUE(ImagesAreEqual(icon3, folder_image_.icon()));
+
+  // Delete an item. Ensure that the observer fired and the icon changed.
+  app_list_model_.DeleteItem("app2");
+  EXPECT_TRUE(observer_.updated());
+  observer_.Reset();
+  gfx::ImageSkia icon4 = folder_image_.icon();
+  EXPECT_FALSE(ImagesAreEqual(icon3, icon4));
+}
+
+TEST_F(FolderImageTest, UpdateItemTest) {
+  gfx::ImageSkia icon1 = folder_image_.icon();
+
+  // Change an item's icon. Ensure that the observer fired and the icon changed.
+  app_list_model_.FindItem("app2")->SetIcon(
+      CreateSquareBitmapWithColor(kListIconSize, SK_ColorMAGENTA), false);
+  EXPECT_TRUE(observer_.updated());
+  observer_.Reset();
+  EXPECT_FALSE(ImagesAreEqual(icon1, folder_image_.icon()));
+}
+
+}  // namespace app_list