Invalidate paint properties on paint offset changes

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/html/HTMLIFrameElement.h"
 #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"
@@ skipping 3011 matching lines @@
   EXPECT_FALSE(document().layoutView()->needsPaintPropertyUpdate());
   EXPECT_FALSE(document().layoutView()->descendantNeedsPaintPropertyUpdate());
   EXPECT_FALSE(transform->needsPaintPropertyUpdate());
   EXPECT_FALSE(transform->descendantNeedsPaintPropertyUpdate());
   EXPECT_FALSE(iframeLayoutView->needsPaintPropertyUpdate());
   EXPECT_FALSE(iframeLayoutView->descendantNeedsPaintPropertyUpdate());
   EXPECT_FALSE(iframeTransform->needsPaintPropertyUpdate());
   EXPECT_FALSE(iframeTransform->descendantNeedsPaintPropertyUpdate());
 }
 
+TEST_P(PaintPropertyTreeBuilderTest, OverflowClipRecomputedOnChange) {
+  setBodyInnerHTML(
+      "<style>"
+      "body { margin:0 }"
+      "#div { overflow:hidden; height:0px; }"
+      "</style>"
+      "<div id='div'></div>");
+  auto* div = document().getElementById("div");
+  div->setAttribute(HTMLNames::styleAttr, "display:inline-block; width:7px;");
+  document().view()->updateAllLifecyclePhases();
+  auto* properties = div->layoutObject()->paintProperties()->overflowClip();
+  EXPECT_EQ(FloatRect(0, 0, 7, 0), properties->clipRect().rect());
+
+  // Width changes should update the overflow clip.
+  div->setAttribute(HTMLNames::styleAttr, "display:inline-block; width:7px;");
+  document().view()->updateAllLifecyclePhases();
+  properties = div->layoutObject()->paintProperties()->overflowClip();
+  EXPECT_EQ(FloatRect(0, 0, 7, 0), properties->clipRect().rect());
+  div->setAttribute(HTMLNames::styleAttr, "display:inline-block; width:9px;");
+  document().view()->updateAllLifecyclePhases();
+  EXPECT_EQ(FloatRect(0, 0, 9, 0), properties->clipRect().rect());
+
+  // An inline block's overflow clip should be updated when padding changes,
+  // even if the border box remains unchanged.
+  div->setAttribute(HTMLNames::styleAttr,
+                    "display:inline-block; width:7px; padding-right:3px;");
+  document().view()->updateAllLifecyclePhases();
+  properties = div->layoutObject()->paintProperties()->overflowClip();
+  EXPECT_EQ(FloatRect(0, 0, 10, 0), properties->clipRect().rect());
+  div->setAttribute(HTMLNames::styleAttr,
+                    "display:inline-block; width:8px; padding-right:2px;");
+  document().view()->updateAllLifecyclePhases();
+  EXPECT_EQ(FloatRect(0, 0, 10, 0), properties->clipRect().rect());
+  div->setAttribute(HTMLNames::styleAttr,
+                    "display:inline-block; width:8px;"
+                    "padding-right:1px; padding-left:1px;");
+  document().view()->updateAllLifecyclePhases();
+  EXPECT_EQ(FloatRect(0, 0, 10, 0), properties->clipRect().rect());
+
+  // An block's overflow clip should be updated when borders change.
+  div->setAttribute(HTMLNames::styleAttr, "border-right:3px solid red;");
+  document().view()->updateAllLifecyclePhases();
+  properties = div->layoutObject()->paintProperties()->overflowClip();
+  EXPECT_EQ(FloatRect(0, 0, 797, 0), properties->clipRect().rect());
+  div->setAttribute(HTMLNames::styleAttr, "border-right:5px solid red;");
+  document().view()->updateAllLifecyclePhases();
+  EXPECT_EQ(FloatRect(0, 0, 795, 0), properties->clipRect().rect());
+}
+
 }  // namespace blink