Add test for PdfMetafileCg::RenderPage().

Add a basic test to make sure RenderPage() works correctly for simple
rendering.

Change-Id: I2b2fd287167c532cb2f35c50726b880f56cb496b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2117354
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Daniel Hosseinian <dhoss@chromium.org>
Cr-Commit-Position: refs/heads/master@{#753069}

printing/BUILD.gn

@@ -317,7 +317,10 @@ test("printing_unittests") {
     "//ui/gfx/geometry",
   ]
 
-  data = [ "../pdf/test/data/" ]
+  data = [
+    "test/data/",
+    "../pdf/test/data/",
+  ]
 
   if (is_win || is_mac) {
     sources += [ "printed_document_unittest.cc" ]

printing/pdf_metafile_cg_mac_unittest.cc

@@ -11,8 +11,10 @@
 #include <vector>
 
 #include "base/files/file_util.h"
+#include "base/hash/sha1.h"
 #include "base/path_service.h"
 #include "testing/gtest/include/gtest/gtest.h"
+#include "ui/gfx/codec/png_codec.h"
 #include "ui/gfx/geometry/rect.h"
 
 namespace printing {
@@ -26,6 +28,17 @@ base::FilePath GetPdfTestData(const base::FilePath::StringType& filename) {
   return root_path.Append("pdf").Append("test").Append("data").Append(filename);
 }
 
+base::FilePath GetPrintingTestData(const base::FilePath::StringType& filename) {
+  base::FilePath root_path;
+  if (!base::PathService::Get(base::DIR_SOURCE_ROOT, &root_path))
+    return base::FilePath();
+  return root_path.Append("printing")
+      .Append("test")
+      .Append("data")
+      .Append("pdf_cg")
+      .Append(filename);
+}
+
 }  // namespace
 
 TEST(PdfMetafileCgTest, Pdf) {
@@ -111,4 +124,65 @@ TEST(PdfMetafileCgTest, GetPageBounds) {
   }
 }
 
+TEST(PdfMetafileCgTest, RenderPageBasic) {
+  // Get test data.
+  base::FilePath pdf_file = GetPdfTestData("rectangles.pdf");
+  ASSERT_FALSE(pdf_file.empty());
+  std::string pdf_data;
+  ASSERT_TRUE(base::ReadFileToString(pdf_file, &pdf_data));
+
+  base::FilePath expected_png_file =
+      GetPrintingTestData("rectangles_cg_expected.pdf.0.png");
+  ASSERT_FALSE(expected_png_file.empty());
+  std::string expected_png_data;
+  ASSERT_TRUE(base::ReadFileToString(expected_png_file, &expected_png_data));
+
+  // Initialize and check metafile.
+  constexpr int kExpectedWidth = 200;
+  constexpr int kExpectedHeight = 300;
+  PdfMetafileCg pdf_cg;
+  ASSERT_TRUE(pdf_cg.InitFromData(pdf_data.data(), pdf_data.size()));
+  ASSERT_EQ(1u, pdf_cg.GetPageCount());
+  gfx::Rect bounds = pdf_cg.GetPageBounds(1);
+  ASSERT_EQ(0, bounds.x());
+  ASSERT_EQ(0, bounds.y());
+  ASSERT_EQ(kExpectedWidth, bounds.width());
+  ASSERT_EQ(kExpectedHeight, bounds.height());
+
+  // Set up rendering context.
+  constexpr size_t kBitsPerComponent = 8;
+  constexpr size_t kBytesPerPixel = 4;
+  constexpr size_t kStride = kExpectedWidth * kBytesPerPixel;
+  std::vector<uint8_t> rendered_bitmap(kStride * kExpectedHeight);
+  base::ScopedCFTypeRef<CGColorSpaceRef> color_space(
+      CGColorSpaceCreateDeviceRGB());
+  base::ScopedCFTypeRef<CGContextRef> context(CGBitmapContextCreate(
+      rendered_bitmap.data(), kExpectedWidth, kExpectedHeight,
+      kBitsPerComponent, kStride, color_space,
+      kCGImageAlphaPremultipliedFirst | kCGBitmapByteOrder32Little));
+
+  // Render using metafile and calculate the output hash.
+  Metafile::MacRenderPageParams params;
+  params.autorotate = true;
+  ASSERT_TRUE(pdf_cg.RenderPage(1, context, bounds.ToCGRect(), params));
+  std::array<uint8_t, base::kSHA1Length> rendered_hash =
+      base::SHA1HashSpan(rendered_bitmap);
+
+  // Decode expected PNG and calculate the output hash.
+  std::vector<uint8_t> expected_png_bitmap;
+  int png_width;
+  int png_height;
+  ASSERT_TRUE(gfx::PNGCodec::Decode(
+      reinterpret_cast<const uint8_t*>(expected_png_data.data()),
+      expected_png_data.size(), gfx::PNGCodec::FORMAT_BGRA,
+      &expected_png_bitmap, &png_width, &png_height));
+  ASSERT_EQ(kExpectedWidth, png_width);
+  ASSERT_EQ(kExpectedHeight, png_height);
+  std::array<uint8_t, base::kSHA1Length> expected_hash =
+      base::SHA1HashSpan(expected_png_bitmap);
+
+  // Make sure the hashes match.
+  EXPECT_EQ(expected_hash, rendered_hash);
+}
+
 }  // namespace printing

printing/test/data/pdf_cg/README.md

@@ -0,0 +1,6 @@
+pdf_cg test expectations
+---
+The PNG files in this directory are the CoreGraphics rendering outputs for PDFs
+in //pdf/test/data/. They are generated from raw bitmaps using
+gfx::PNGCodec::Encode() using the |gfx::PNGCodec::FORMAT_BGRA| format. The PNGs
+are further optimized with optipng.