Create a Factory for NativeMetafile.

printing/emf_win_unittest.cc

Index: printing/emf_win_unittest.cc
diff --git a/printing/emf_win_unittest.cc b/printing/emf_win_unittest.cc
index 4312b2ca7c389549ab40b3626f1e2a6eff086edd..080fea8243049f3006c2fbe997758219866699f5 100644
--- a/printing/emf_win_unittest.cc
+++ b/printing/emf_win_unittest.cc
@@ -15,6 +15,7 @@
 #include "base/scoped_ptr.h"
 #include "base/scoped_temp_dir.h"
 #include "base/win/scoped_hdc.h"
+#include "printing/metafile_factory.h"
 #include "printing/printing_context.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ -195,3 +196,31 @@ TEST(EmfTest, FileBackedDC) {
   emf.CloseEmf();
 }
 
+TEST(EmfTest, DCFactory) {
+  // Simplest use case.
+  scoped_ptr<printing::NativeMetafile> emf_ptr(
+      printing::MetafileFactory::GetMetafile());
+  RECT rect = {100, 100, 200, 200};
+  HDC hdc = CreateCompatibleDC(NULL);
+  EXPECT_TRUE(hdc != NULL);
+  EXPECT_TRUE(emf_ptr->CreateDc(hdc, &rect));
+  EXPECT_TRUE(emf_ptr->hdc() != NULL);
+  // In theory, you'd use the HDC with GDI functions here.
+  EXPECT_TRUE(emf_ptr->CloseDc());
+  uint32 size = emf_ptr->GetDataSize();
+  EXPECT_EQ(size, EMF_HEADER_SIZE);
+  std::vector<BYTE> data;
+  EXPECT_TRUE(emf_ptr->GetData(&data));
+  EXPECT_EQ(data.size(), size);
+  emf_ptr->CloseEmf();
+  EXPECT_TRUE(DeleteDC(hdc));
+
+  // Playback the data.
+  hdc = CreateCompatibleDC(NULL);
+  EXPECT_TRUE(hdc);
+  EXPECT_TRUE(emf_ptr->Init(&data.front(), size));
+  RECT output_rect = {0, 0, 10, 10};
+  EXPECT_TRUE(emf_ptr->Playback(hdc, &output_rect));
+  EXPECT_TRUE(DeleteDC(hdc));
+}
+