add local caching for skia draws

core/fxge/skia/fx_skia_device_unittest.cpp

Index: core/fxge/skia/fx_skia_device_unittest.cpp
diff --git a/core/fxge/skia/fx_skia_device_unittest.cpp b/core/fxge/skia/fx_skia_device_unittest.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..eb7559b5e2348ee3dc435155c25c9caf8dff2ca0
--- /dev/null
+++ b/core/fxge/skia/fx_skia_device_unittest.cpp
@@ -0,0 +1,164 @@
+// Copyright 2016 PDFium 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 "core/fxge/include/fx_ge.h"
+#include "core/fxge/skia/fx_skia_device.h"
+#include "fpdfsdk/include/fsdk_define.h"
+#include "public/fpdfview.h"
+#include "testing/fx_string_testhelpers.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "third_party/skia/include/core/SkPictureRecorder.h"
+
+namespace {
+
+struct State {
+  enum class Change { kNo, kYes };
+  enum class Save { kNo, kYes };
+  enum class Clip { kNo, kSame, kDifferentPath, kDifferentMatrix };
+  enum class Graphic { kNone, kPath, kText };
+
+  Change m_change;
+  Save m_save;
+  Clip m_clip;
+  Graphic m_graphic;
+  uint32_t m_pixel;
+};
+
+void EmptyTest(CFX_SkiaDeviceDriver* driver, const State&) {
+  driver->SaveState();
+  driver->RestoreState(true);
+  driver->RestoreState(false);
+}
+
+void CommonTest(CFX_SkiaDeviceDriver* driver, const State& state) {
+  FXTEXT_CHARPOS charPos[] = {1, 0, 1, 4, false, {0, 0, 0, 0}, false};
+  CFX_Font font;
+  FX_FLOAT fontSize = 1;
+  CFX_FontCache cache;
+  CFX_PathData clipPath, clipPath2;
+  clipPath.AppendRect(0, 0, 3, 1);
+  clipPath2.AppendRect(0, 0, 2, 1);
+  CFX_Matrix clipMatrix;
+  CFX_Matrix clipMatrix2(1, 0, 0, 1, 0, 1);
+  driver->SaveState();
+  CFX_PathData path1;
+  path1.AppendRect(0, 0, 1, 2);
+  CFX_Matrix matrix, matrix2;
+  matrix2.Translate(1, 0);
+  CFX_GraphStateData graphState;
+  if (state.m_save == State::Save::kYes)
+    driver->SaveState();
+  if (state.m_clip != State::Clip::kNo)
+    driver->SetClip_PathFill(&clipPath, &clipMatrix, 0);
+  if (state.m_graphic == State::Graphic::kPath) {
+    driver->DrawPath(&path1, &matrix, &graphState, 0xFF112233, 0,
+                     FXFILL_WINDING, 0);
+  } else if (state.m_graphic == State::Graphic::kText) {
+    driver->DrawDeviceText(SK_ARRAY_COUNT(charPos), charPos, &font, &cache,
+                           &matrix, fontSize, 0xFF445566);
+  }
+  if (state.m_save == State::Save::kYes)
+    driver->RestoreState(true);
+  CFX_PathData path2;
+  path2.AppendRect(0, 0, 2, 2);
+  if (state.m_change == State::Change::kYes) {
+    if (state.m_graphic == State::Graphic::kPath)
+      graphState.m_LineCap = CFX_GraphStateData::LineCapRound;
+    else if (state.m_graphic == State::Graphic::kText)
+      fontSize = 2;
+  }
+  if (state.m_clip == State::Clip::kSame)
+    driver->SetClip_PathFill(&clipPath, &clipMatrix, 0);
+  else if (state.m_clip == State::Clip::kDifferentPath)
+    driver->SetClip_PathFill(&clipPath2, &clipMatrix, 0);
+  else if (state.m_clip == State::Clip::kDifferentMatrix)
+    driver->SetClip_PathFill(&clipPath, &clipMatrix2, 0);
+  if (state.m_graphic == State::Graphic::kPath) {
+    driver->DrawPath(&path2, &matrix2, &graphState, 0xFF112233, 0,
+                     FXFILL_WINDING, 0);
+  } else if (state.m_graphic == State::Graphic::kText) {
+    driver->DrawDeviceText(SK_ARRAY_COUNT(charPos), charPos, &font, &cache,
+                           &matrix2, fontSize, 0xFF445566);
+  }
+  if (state.m_save == State::Save::kYes)
+    driver->RestoreState(false);
+  driver->RestoreState(false);
+}
+
+void OutOfSequenceClipTest(CFX_SkiaDeviceDriver* driver, const State&) {
+  CFX_PathData clipPath;
+  clipPath.AppendRect(1, 0, 3, 1);
+  CFX_Matrix clipMatrix;
+  driver->SaveState();
+  driver->SetClip_PathFill(&clipPath, &clipMatrix, 0);
+  driver->RestoreState(true);
+  driver->SaveState();
+  driver->SetClip_PathFill(&clipPath, &clipMatrix, 0);
+  driver->RestoreState(false);
+  driver->RestoreState(false);
+
+  driver->SaveState();
+  driver->SaveState();
+  driver->SetClip_PathFill(&clipPath, &clipMatrix, 0);
+  driver->RestoreState(true);
+  driver->SetClip_PathFill(&clipPath, &clipMatrix, 0);
+  driver->RestoreState(false);
+  driver->RestoreState(false);
+}
+
+void Harness(void (*Test)(CFX_SkiaDeviceDriver*, const State&),
+             const State& state) {
+  int h = 1;
+  int w = 4;
+  FPDF_BITMAP bitmap = FPDFBitmap_Create(w, h, 1);
+  EXPECT_NE(nullptr, bitmap);
+  if (!bitmap)
+    return;
+  FPDFBitmap_FillRect(bitmap, 0, 0, w, h, 0x00000000);
+  CFX_FxgeDevice geDevice;
+  CFX_DIBitmap* pBitmap = CFXBitmapFromFPDFBitmap(bitmap);
+  geDevice.Attach(pBitmap, false, nullptr, false);
+  CFX_SkiaDeviceDriver* driver =
+      static_cast<CFX_SkiaDeviceDriver*>(geDevice.GetDeviceDriver());
+  (*Test)(driver, state);
+  driver->Flush();
+  uint32_t pixel = pBitmap->GetPixel(0, 0);
+  EXPECT_EQ(state.m_pixel, pixel);
+#ifdef SK_DEBUG
+  if (!driver)  // force dump to be linked in so it can be called from debugger
+    driver->Dump();
+#endif
+}
+
+}  // namespace
+
+TEST(fxge, SkiaStateEmpty) {
+  Harness(&EmptyTest, {});
+}
+
+TEST(fxge, SkiaStatePath) {
+  Harness(&CommonTest, {State::Change::kNo, State::Save::kYes,
+                        State::Clip::kSame, State::Graphic::kPath, 0xFF112233});
+  Harness(&CommonTest,
+          {State::Change::kNo, State::Save::kYes, State::Clip::kDifferentPath,
+           State::Graphic::kPath, 0xFF112233});
+  Harness(&CommonTest, {State::Change::kNo, State::Save::kYes, State::Clip::kNo,
+                        State::Graphic::kPath, 0xFF112233});
+  Harness(&CommonTest, {State::Change::kYes, State::Save::kNo, State::Clip::kNo,
+                        State::Graphic::kPath, 0xFF112233});
+  Harness(&CommonTest, {State::Change::kNo, State::Save::kNo, State::Clip::kNo,
+                        State::Graphic::kPath, 0xFF112233});
+}
+
+TEST(fxge, SkiaStateText) {
+  Harness(&CommonTest,
+          {State::Change::kNo, State::Save::kYes, State::Clip::kDifferentMatrix,
+           State::Graphic::kText, 0xFF445566});
+  Harness(&CommonTest, {State::Change::kNo, State::Save::kYes,
+                        State::Clip::kSame, State::Graphic::kText, 0xFF445566});
+}
+
+TEST(fxge, SkiaStateOOSClip) {
+  Harness(&OutOfSequenceClipTest, {});
+}