(WIP) Paint property hierarchy approach 1 of 2

third_party/WebKit/Source/platform/graphics/paint/PaintChunkerTest.cpp

 // Copyright 2015 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 "config.h"
 #include "platform/graphics/paint/PaintChunker.h"
 
 #include "platform/RuntimeEnabledFeatures.h"
 #include <gmock/gmock.h>
 #include <gtest/gtest.h>
 
 using testing::ElementsAre;
 
 namespace blink {
 namespace {
 
-static PaintProperties samplePaintProperties() { return PaintProperties(); }
+static PaintProperties rootPaintProperties() { return PaintProperties(); }
 
 class PaintChunkerTest : public testing::Test {
 protected:
     void SetUp() override
     {
         RuntimeEnabledFeatures::setSlimmingPaintV2Enabled(true);
     }
 
     void TearDown() override
     {
         m_featuresBackup.restore();
     }
 
 private:
     RuntimeEnabledFeatures::Backup m_featuresBackup;
 };
 
 TEST_F(PaintChunkerTest, Empty)
 {
     Vector<PaintChunk> chunks = PaintChunker().releasePaintChunks();
     ASSERT_TRUE(chunks.isEmpty());
 }
 
 TEST_F(PaintChunkerTest, SingleNonEmptyRange)
 {
     PaintChunker chunker;
-    chunker.updateCurrentPaintProperties(samplePaintProperties());
+    chunker.updateCurrentPaintProperties(rootPaintProperties());
     chunker.incrementDisplayItemIndex();
     chunker.incrementDisplayItemIndex();
     Vector<PaintChunk> chunks = chunker.releasePaintChunks();
 
     EXPECT_THAT(chunks, ElementsAre(
-        PaintChunk(0, 2, samplePaintProperties())));
+        PaintChunk(0, 2, rootPaintProperties())));
 }
 
 TEST_F(PaintChunkerTest, SamePropertiesTwiceCombineIntoOneChunk)
 {
     PaintChunker chunker;
-    chunker.updateCurrentPaintProperties(samplePaintProperties());
+    chunker.updateCurrentPaintProperties(rootPaintProperties());
     chunker.incrementDisplayItemIndex();
     chunker.incrementDisplayItemIndex();
-    chunker.updateCurrentPaintProperties(samplePaintProperties());
+    chunker.updateCurrentPaintProperties(rootPaintProperties());
     chunker.incrementDisplayItemIndex();
     Vector<PaintChunk> chunks = chunker.releasePaintChunks();
 
     EXPECT_THAT(chunks, ElementsAre(
-        PaintChunk(0, 3, samplePaintProperties())));
+        PaintChunk(0, 3, rootPaintProperties())));
 }
 
 TEST_F(PaintChunkerTest, CanRewindDisplayItemIndex)
 {
     PaintChunker chunker;
-    chunker.updateCurrentPaintProperties(samplePaintProperties());
+    chunker.updateCurrentPaintProperties(rootPaintProperties());
     chunker.incrementDisplayItemIndex();
     chunker.incrementDisplayItemIndex();
     chunker.decrementDisplayItemIndex();
     chunker.incrementDisplayItemIndex();
     Vector<PaintChunk> chunks = chunker.releasePaintChunks();
 
     EXPECT_THAT(chunks, ElementsAre(
-        PaintChunk(0, 2, samplePaintProperties())));
+        PaintChunk(0, 2, rootPaintProperties())));
 }
 
-// TODO(jbroman): Add more tests one it is possible for there to be two distinct
-// PaintProperties.
+TEST_F(PaintChunkerTest, BuildMultipleChunksWithSinglePropertyChanging)
+{
+    PaintChunker chunker;
+    chunker.updateCurrentPaintProperties(rootPaintProperties());
+    chunker.incrementDisplayItemIndex();
+    chunker.incrementDisplayItemIndex();
+
+    PaintProperties aTransform;
+    aTransform.transformIndex = 1;
+    chunker.updateCurrentPaintProperties(aTransform);
+    chunker.incrementDisplayItemIndex();
+
+    PaintProperties bTransform;
+    bTransform.transformIndex = 2;
+    chunker.updateCurrentPaintProperties(bTransform);
+    chunker.incrementDisplayItemIndex();
+
+    Vector<PaintChunk> chunks = chunker.releasePaintChunks();
+
+    EXPECT_THAT(chunks, ElementsAre(
+        PaintChunk(0, 2, rootPaintProperties()),
+        PaintChunk(2, 3, aTransform),
+        PaintChunk(3, 4, bTransform)));
+}
+
+TEST_F(PaintChunkerTest, BuildLinearChunksFromNestedTransforms)
+{
+    // Test that "nested" transforms linearize using the following
+    // sequence of transforms and display items:
+    // <root xform>, <paint>, <a xform>, <paint>, <paint>, </a xform>, <paint>, </root xform>
+    PaintChunker chunker;
+    chunker.updateCurrentPaintProperties(rootPaintProperties());
+    chunker.incrementDisplayItemIndex();
+
+    PaintProperties aTransform;
+    aTransform.transformIndex = 1;
+    chunker.updateCurrentPaintProperties(aTransform);
+    chunker.incrementDisplayItemIndex();
+    chunker.incrementDisplayItemIndex();
+
+    chunker.updateCurrentPaintProperties(rootPaintProperties());
+    chunker.incrementDisplayItemIndex();
+
+    Vector<PaintChunk> chunks = chunker.releasePaintChunks();
+
+    EXPECT_THAT(chunks, ElementsAre(
+        PaintChunk(0, 1, rootPaintProperties()),
+        PaintChunk(1, 3, aTransform),
+        PaintChunk(3, 4, rootPaintProperties())));
+}
+
+// TODO(pdr): Add more tests once we have more paint properties.
 
 } // namespace
 } // namespace blink