[SPInvalidation] Handle pixel-snapping of paint invalidation rects

third_party/WebKit/Source/core/paint/PaintPropertyTreeBuilderTest.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 "core/layout/LayoutTestHelper.h"
 #include "core/layout/LayoutTreeAsText.h"
 #include "core/layout/api/LayoutViewItem.h"
 #include "core/paint/ObjectPaintProperties.h"
 #include "core/paint/PaintPropertyTreePrinter.h"
 #include "platform/graphics/paint/GeometryMapper.h"
@@ skipping 1680 matching lines @@
       rectWithTransform.paintProperties();
   EXPECT_EQ(TransformationMatrix().translate(1, 1),
             rectWithTransformProperties->transform()->matrix());
 
   // Ensure there is no PaintOffset transform between the rect and the svg's
   // transform.
   EXPECT_EQ(svgWithTransformProperties->transform(),
             rectWithTransformProperties->transform()->parent());
 }
 
+TEST_P(PaintPropertyTreeBuilderTest, SvgRootAndForeignObjectPixelSnapping) {
+  setBodyInnerHTML(
+      "<svg id=svg style='position: relative; left: 0.6px; top: 0.3px'>"
+      "  <foreignObject id=foreign x='3.5' y='5.4' transform='translate(1,1)'>"
+      "    <div id=div style='position: absolute; left: 5.6px; top: 7.3px'>"
+      "    </div>"
+      "  </foreignObject>"
+      "</svg>");
+
+  const auto* svgProperties =
+      getLayoutObjectByElementId("svg")->paintProperties();
+  EXPECT_EQ(nullptr, svgProperties->paintOffsetTranslation());
+  EXPECT_EQ(LayoutPoint(LayoutUnit(8.6), LayoutUnit(8.3)),
+            svgProperties->localBorderBoxProperties()->paintOffset);
+  // Paint offset of SVGRoot be baked into svgLocalToBorderBoxTransform after
+  // snapped to pixels.
+  EXPECT_EQ(TransformationMatrix().translate(9, 8),
+            svgProperties->svgLocalToBorderBoxTransform()->matrix());
+
+  const auto* foreignObjectProperties =
+      getLayoutObjectByElementId("foreign")->paintProperties();
+  EXPECT_EQ(nullptr, foreignObjectProperties->paintOffsetTranslation());
+  // Paint offset of foreignObject should be originated from SVG root and
+  // snapped to pixels.
+  EXPECT_EQ(LayoutPoint(4, 5),
+            foreignObjectProperties->localBorderBoxProperties()->paintOffset);
+
+  const auto* divProperties =
+      getLayoutObjectByElementId("div")->paintProperties();
+  // Paint offset of descendant of foreignObject accumulates on paint offset of
+  // foreignObject.
+  EXPECT_EQ(LayoutPoint(LayoutUnit(4 + 5.6), LayoutUnit(5 + 7.3)),
+            divProperties->localBorderBoxProperties()->paintOffset);
+}
+
 TEST_P(PaintPropertyTreeBuilderTest, NoRenderingContextByDefault) {
   setBodyInnerHTML("<div style='transform: translateZ(0)'></div>");
 
   const ObjectPaintProperties* properties =
       document().body()->firstChild()->layoutObject()->paintProperties();
   ASSERT_TRUE(properties->transform());
   EXPECT_FALSE(properties->transform()->hasRenderingContext());
 }
 
 TEST_P(PaintPropertyTreeBuilderTest, Preserve3DCreatesSharedRenderingContext) {
@@ skipping 1143 matching lines @@
       "      <div id=absolute style='position: absolute'>absolute</div>"
       "    </div>"
       "  </span>"
       "</div>");
   // There should be anonymous block created containing the inline "relative",
   // serving as the container of "absolute".
   EXPECT_TRUE(
       getLayoutObjectByElementId("absolute")->container()->isLayoutBlock());
 }
 }  // namespace blink