chromium/ash/wallpaper/wallpaper_utils/wallpaper_resizer_unittest.cc

// Copyright 2018 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "ash/wallpaper/wallpaper_utils/wallpaper_resizer.h"

#include <stdint.h>

#include <memory>

#include "ash/public/cpp/wallpaper/wallpaper_types.h"
#include "base/functional/callback.h"
#include "base/run_loop.h"
#include "base/test/metrics/histogram_tester.h"
#include "base/test/task_environment.h"
#include "base/time/time.h"
#include "testing/gtest/include/gtest/gtest.h"
#include "third_party/skia/include/core/SkColor.h"
#include "ui/gfx/image/image_skia.h"
#include "ui/gfx/image/image_skia_rep.h"

namespace ash {
namespace {

const int kTestImageWidth = 5;
const int kTestImageHeight = 2;
const int kTargetWidth = 1;
const int kTargetHeight = 1;
const uint32_t kExpectedCenter = 0xFF020202u;
const uint32_t kExpectedCenterCropped = 0xFF030303u;
const uint32_t kExpectedStretch = 0xFF040404u;
const uint32_t kExpectedTile = 0xFF000000u;

gfx::ImageSkia CreateTestImage(const gfx::Size& size) {
  SkBitmap src;
  int w = size.width();
  int h = size.height();
  src.allocN32Pixels(w, h);

  // Fill bitmap with data.
  for (int y = 0; y < h; ++y) {
    for (int x = 0; x < w; ++x) {
      const uint8_t component = static_cast<uint8_t>(y * w + x);
      const SkColor pixel =
          SkColorSetARGB(component, component, component, component);
      *(src.getAddr32(x, y)) = pixel;
    }
  }

  gfx::ImageSkia image = gfx::ImageSkia::CreateFrom1xBitmap(src);
  return image;
}

bool IsColor(const gfx::ImageSkia& image, const uint32_t expect) {
  EXPECT_EQ(image.width(), kTargetWidth);
  EXPECT_EQ(image.height(), kTargetHeight);
  return *image.bitmap()->getAddr32(0, 0) == expect;
}

}  // namespace

namespace wallpaper {

class WallpaperResizerTest : public testing::Test {
 public:
  WallpaperResizerTest() = default;

  WallpaperResizerTest(const WallpaperResizerTest&) = delete;
  WallpaperResizerTest& operator=(const WallpaperResizerTest&) = delete;

  ~WallpaperResizerTest() override = default;

  gfx::ImageSkia Resize(const gfx::ImageSkia& image,
                        const gfx::Size& target_size,
                        WallpaperLayout layout) {
    WallpaperResizer resizer(image, target_size,
                             WallpaperInfo("", layout, WallpaperType::kDefault,
                                           base::Time::Now().LocalMidnight()));
    base::RunLoop loop;
    resizer.StartResize(loop.QuitClosure());
    loop.Run();
    return resizer.image();
  }

 private:
  base::test::TaskEnvironment task_environment_;
};

TEST_F(WallpaperResizerTest, BasicResize) {
  // Keeps in sync with WallpaperLayout enum.
  WallpaperLayout layouts[4] = {
      WALLPAPER_LAYOUT_CENTER,
      WALLPAPER_LAYOUT_CENTER_CROPPED,
      WALLPAPER_LAYOUT_STRETCH,
      WALLPAPER_LAYOUT_TILE,
  };

  for (auto layout : layouts) {
    gfx::ImageSkia small_image(gfx::ImageSkiaRep(gfx::Size(10, 20), 1.0f));

    gfx::ImageSkia resized_small =
        Resize(small_image, gfx::Size(800, 600), layout);
    EXPECT_EQ(10, resized_small.width());
    EXPECT_EQ(20, resized_small.height());

    gfx::ImageSkia large_image(gfx::ImageSkiaRep(gfx::Size(1000, 1000), 1.0f));
    gfx::ImageSkia resized_large =
        Resize(large_image, gfx::Size(800, 600), layout);
    EXPECT_EQ(800, resized_large.width());
    EXPECT_EQ(600, resized_large.height());
  }
}

// Test for crbug.com/244629. "CENTER_CROPPED generates the same image as
// STRETCH layout"
TEST_F(WallpaperResizerTest, AllLayoutDifferent) {
  gfx::ImageSkia image =
      CreateTestImage(gfx::Size(kTestImageWidth, kTestImageHeight));

  gfx::Size target_size = gfx::Size(kTargetWidth, kTargetHeight);
  gfx::ImageSkia center = Resize(image, target_size, WALLPAPER_LAYOUT_CENTER);

  gfx::ImageSkia center_cropped =
      Resize(image, target_size, WALLPAPER_LAYOUT_CENTER_CROPPED);

  gfx::ImageSkia stretch = Resize(image, target_size, WALLPAPER_LAYOUT_STRETCH);

  gfx::ImageSkia tile = Resize(image, target_size, WALLPAPER_LAYOUT_TILE);

  EXPECT_TRUE(IsColor(center, kExpectedCenter));
  EXPECT_TRUE(IsColor(center_cropped, kExpectedCenterCropped));
  EXPECT_TRUE(IsColor(stretch, kExpectedStretch));
  EXPECT_TRUE(IsColor(tile, kExpectedTile));
}

TEST_F(WallpaperResizerTest, ImageId) {
  gfx::ImageSkia image =
      CreateTestImage(gfx::Size(kTestImageWidth, kTestImageHeight));

  // Create a WallpaperResizer and check that it reports an original image ID
  // both pre- and post-resize that matches the ID returned by GetImageId().
  WallpaperResizer resizer(
      image, gfx::Size(10, 20),
      WallpaperInfo("", WALLPAPER_LAYOUT_STRETCH, WallpaperType::kDefault,
                    base::Time::Now().LocalMidnight()));
  EXPECT_EQ(WallpaperResizer::GetImageId(image), resizer.original_image_id());
  base::RunLoop loop;
  resizer.StartResize(loop.QuitClosure());
  loop.Run();
  EXPECT_EQ(WallpaperResizer::GetImageId(image), resizer.original_image_id());
}

TEST_F(WallpaperResizerTest, RecordsDecodedSize) {
  base::HistogramTester histogram_tester;
  gfx::ImageSkia image = CreateTestImage(gfx::Size(3000, 3000));

  WallpaperResizer resizer(image, gfx::Size(2000, 1000),
                           WallpaperInfo("", WALLPAPER_LAYOUT_CENTER_CROPPED,
                                         WallpaperType::kDefault,
                                         base::Time::Now().LocalMidnight()));
  histogram_tester.ExpectTotalCount("Ash.Wallpaper.DecodedSizeMB", 0);
  base::RunLoop loop;
  resizer.StartResize(loop.QuitClosure());
  loop.Run();

  // 3000x3000 image should be shrunk down to 2000x1000. 2000 * 1000 *
  // 4 bytes per pixel (RGBA) ~= 8 MB.
  histogram_tester.ExpectUniqueSample("Ash.Wallpaper.DecodedSizeMB", 8, 1);
}

}  // namespace wallpaper
}  // namespace ash