ShadowRoot interface should have elementFromPoint

https://bugs.webkit.org/show_bug.cgi?id=162882

Reviewed by Chris Dumez.

Source/WebCore:

Add elementFromPoint to ShadowRoot's prototype as specified at:
https://www.w3.org/TR/shadow-dom/#extensions-to-the-documentorshadowroot-mixin
with changes proposed at w3c/csswg-drafts#556

Added TreeScope::retargetToScope which implements

This patch also factors DocumentOrShadowRoot.idl out of Document and ShadowRoot interfaces to better match
the latest DOM specification: https://dom.spec.whatwg.org/#mixin-documentorshadowroot

Test: fast/shadow-dom/Document-prototype-elementFromPoint.html

* CMakeLists.txt:
* DerivedSources.make:
* WebCore.xcodeproj/project.pbxproj:
* dom/Document.cpp:
(WebCore::Document::nodeFromPoint): Moved to TreeScope.
(WebCore::Document::elementFromPoint): Moved to TreeScope.
* dom/Document.h:
* dom/Document.idl: Moved elementFromPoint and activeElement to DocumentOrShadowRoot.idl.
* dom/DocumentOrShadowRoot.idl: Added.
* dom/EventPath.cpp:
(WebCore::RelatedNodeRetargeter::checkConsistency): Use newly added TreeScope::retargetToScope.
* dom/ShadowRoot.idl: Moved activeElement to DocumentOrShadowRoot.idl.
* dom/TreeScope.cpp:
(WebCore::TreeScope::retargetToScope): Added. Implements https://dom.spec.whatwg.org/#retarget efficiently.
Instead of checking whether A (node) is a shadow-including inclusive ancestor of B (this scope) at each
parent, find the lowest ancestor which contains both A and B, and return the self-inclusive ancestor of B
in that tree. To find the lowest common ancestor in O(n), traverse all ancestors of A and B separately and
do a top-down traversal. The last tree scope in which A's ancestor and B's ancestor match is the lowest
common ancestor.
(WebCore::TreeScope::nodeFromPoint): Moved from Document.
(WebCore::TreeScope::elementFromPoint): Moved from Document. Use retargetToScope and parentInComposedTree
instead of parentNode and ancestorInThisScope to match the semantics proposed in
w3c/csswg-drafts#556
* dom/TreeScope.h:

LayoutTests:

Add a W3C style testharness.js test for elementFromPoint on ShadowRoot.

* fast/shadow-dom/DocumentOrShadowRoot-prototype-elementFromPoint-expected.txt: Added.
* fast/shadow-dom/DocumentOrShadowRoot-prototype-elementFromPoint.html: Added.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@206795 268f45cc-cd09-0410-ab3c-d52691b4dbfc

LayoutTests/ChangeLog

@@ -1,3 +1,15 @@
+2016-10-03 Ryosuke Niwa <rniwa@webkit.org>
+
+ ShadowRoot interface should have elementFromPoint
+ https://bugs.webkit.org/show_bug.cgi?id=162882
+
+ Reviewed by Chris Dumez.
+
+ Add a W3C style testharness.js test for elementFromPoint on ShadowRoot.
+
+ * fast/shadow-dom/DocumentOrShadowRoot-prototype-elementFromPoint-expected.txt: Added.
+ * fast/shadow-dom/DocumentOrShadowRoot-prototype-elementFromPoint.html: Added.
+
 2016-10-04 Myles C. Maxfield <mmaxfield@apple.com>
 
  font-family: cursive should map to KaiTi in Chinese

LayoutTests/fast/shadow-dom/DocumentOrShadowRoot-prototype-elementFromPoint-expected.txt

@@ -0,0 +1,35 @@
+
+PASS document.elementFromPoint must return the shadow host of the hit-tested text node when the host has display: inline 
+PASS document.elementFromPoint must return the shadow host of the hit-tested text node when the host has display: block 
+PASS document.elementFromPoint must return the shadow host of the hit-tested text node when the host has display: inline-block 
+PASS document.elementFromPoint must return the shadow host of the hit-tested text node assigned to a slot when the host has display: inline 
+PASS document.elementFromPoint must return the shadow host of the hit-tested text node assigned to a slot when the host has display: block 
+PASS document.elementFromPoint must return the shadow host of the hit-tested text node assigned to a slot when the host has display: inline-block 
+PASS document.elementFromPoint must return the element assigned to a slot when the shadow host of the slot has display: inline 
+PASS document.elementFromPoint must return the element assigned to a slot when the shadow host of the slot has display: block 
+PASS document.elementFromPoint must return the element assigned to a slot when the shadow host of the slot has display: inline-block 
+PASS shadowRoot.elementFromPoint must return the element parent of the hit-tested text node under the point when the shadow host has display: inline 
+PASS shadowRoot.elementFromPoint must return the element parent of the hit-tested text node under the point when the shadow host has display: block 
+PASS shadowRoot.elementFromPoint must return the element parent of the hit-tested text node under the point when the shadow host has display: inline-block 
+PASS shadowRoot.elementFromPoint must return the shadow host when the hit-tested text node is a direct child of the root and the host has display: inline 
+PASS shadowRoot.elementFromPoint must return the shadow host when the hit-tested text node is a direct child of the root and the host has display: block 
+PASS shadowRoot.elementFromPoint must return the shadow host when the hit-tested text node is a direct child of the root and the host has display: inline-block 
+PASS shadowRoot.elementFromPoint must return the slot to which the hit-tested text node is assigned when its host has display: inline 
+PASS shadowRoot.elementFromPoint must return the slot to which the hit-tested text node is assigned when its host has display: block 
+PASS shadowRoot.elementFromPoint must return the slot to which the hit-tested text node is assigned when its host has display: inline-block 
+PASS shadowRoot.elementFromPoint must return the element parent of the hit-tested text node assigned to a slot in the shadow tree when its host has display: inline 
+PASS shadowRoot.elementFromPoint must return the element parent of the hit-tested text node assigned to a slot in the shadow tree when its host has display: block 
+PASS shadowRoot.elementFromPoint must return the element parent of the hit-tested text node assigned to a slot in the shadow tree when its host has display: inline-block 
+PASS shadowRoot.elementFromPoint must return a child element assigned to a slot when the hit-tested text node is assigned to the shadow tree of the child element and the outer shadow host has display: inline 
+PASS shadowRoot.elementFromPoint must return a child element assigned to a slot when the hit-tested text node is assigned to the shadow tree of the child element and the outer shadow host has display: block 
+PASS shadowRoot.elementFromPoint must return a child element assigned to a slot when the hit-tested text node is assigned to the shadow tree of the child element and the outer shadow host has display: inline-block 
+PASS shadowRoot.elementFromPoint must return a child element assigned to a slot when the hit-tested text node is assigned to a slot in the shadow tree of the child element and the outer shadow host has display: inline 
+PASS shadowRoot.elementFromPoint must return a child element assigned to a slot when the hit-tested text node is assigned to a slot in the shadow tree of the child element and the outer shadow host has display: block 
+PASS shadowRoot.elementFromPoint must return a child element assigned to a slot when the hit-tested text node is assigned to a slot in the shadow tree of the child element and the outer shadow host has display: inline-block 
+PASS shadowRoot.elementFromPoint must return a child element with its own shadow tree assigned to a slot when the hit-tested text node is its direct child and the outer shadow host has display: inline 
+PASS shadowRoot.elementFromPoint must return a child element with its own shadow tree assigned to a slot when the hit-tested text node is its direct child and the outer shadow host has display: block 
+PASS shadowRoot.elementFromPoint must return a child element with its own shadow tree assigned to a slot when the hit-tested text node is its direct child and the outer shadow host has display: inline-block 
+PASS shadowRoot.elementFromPoint must return a child element with its own shadow tree assigned to a slot when the hit-tested text node is a child of another element and the outer shadow host has display: inline 
+PASS shadowRoot.elementFromPoint must return a child element with its own shadow tree assigned to a slot when the hit-tested text node is a child of another element and the outer shadow host has display: block 
+PASS shadowRoot.elementFromPoint must return a child element with its own shadow tree assigned to a slot when the hit-tested text node is a child of another element and the outer shadow host has display: inline-block 
+

LayoutTests/fast/shadow-dom/DocumentOrShadowRoot-prototype-elementFromPoint.html

@@ -0,0 +1,204 @@
+<!DOCTYPE html>
+<html>
+<head>
+<title>Shadow DOM and CSSOM View: Document.prototype.elementFromPoint</title>
+<meta name="author" title="Ryosuke Niwa" href="mailto:rniwa@webkit.org">
+<meta name="assert" content="DocumentOrShadowRoot must have elementFromPoint and must return retarget the result against the context object.">
+<link rel="help" href="https://www.w3.org/TR/cssom-view-1/#dom-document-elementfrompoint">
+<link rel="help" href="https://www.w3.org/TR/shadow-dom/#extensions-to-the-documentorshadowroot-mixin">
+<script src="../../resources/testharness.js"></script>
+<script src="../../resources/testharnessreport.js"></script>
+</head>
+<body>
+<div id="container"></div>
+<style>
+
+container { position: relative; }
+test-element { display: block; width: 100px; height: 100px; }
+
+</style>
+<script>
+
+function pointInElement(node) {
+ let x = 5;
+ let y = 5;
+ do {
+ x += node.offsetLeft;
+ y += node.offsetTop;
+ node = node.offsetParent;
+ } while (node);
+ return [x, y];
+}
+
+const displayValues = ['inline', 'block', 'inline-block'];
+var container = document.getElementById('container');
+
+displayValues.forEach(function (displayValue) {
+ test(function () {
+ container.innerHTML = '';
+ let host = document.createElement('test-element');
+ host.style.display = displayValue;
+ let shadow = host.attachShadow({mode: 'closed'});
+ shadow.innerHTML = 'hello';
+ container.appendChild(host);
+ assert_equals(document.elementFromPoint(...pointInElement(host)), host);
+ }, 'document.elementFromPoint must return the shadow host of the hit-tested text node when the host has display: ' + displayValue);
+});
+
+displayValues.forEach(function (displayValue) {
+ test(function () {
+ container.innerHTML = '';
+ let host = document.createElement('test-element');
+ host.style.display = displayValue;
+ let shadow = host.attachShadow({mode: 'closed'});
+ shadow.innerHTML = '<slot></slot>';
+ host.innerHTML = 'text';
+ container.appendChild(host);
+ assert_equals(document.elementFromPoint(...pointInElement(host)), host);
+ }, 'document.elementFromPoint must return the shadow host of the hit-tested text node assigned to a slot when the host has display: ' + displayValue);
+});
+
+displayValues.forEach(function (displayValue) {
+ test(function () {
+ container.innerHTML = '';
+ let host = document.createElement('test-element');
+ host.style.display = displayValue;
+ let shadow = host.attachShadow({mode: 'closed'});
+ shadow.innerHTML = '<slot></slot>';
+ host.innerHTML = '<span>text</span>';
+ container.appendChild(host);
+ assert_equals(document.elementFromPoint(...pointInElement(host)), host.querySelector('span'));
+ }, 'document.elementFromPoint must return the element assigned to a slot when the shadow host of the slot has display: ' + displayValue);
+});
+
+displayValues.forEach(function (displayValue) {
+ test(function () {
+ container.innerHTML = '';
+ let host = document.createElement('test-element');
+ host.style.display = displayValue;
+ let shadow = host.attachShadow({mode: 'closed'});
+ shadow.innerHTML = '<span>text</span>';
+ container.appendChild(host);
+ assert_equals(shadow.elementFromPoint(...pointInElement(shadow.querySelector('span'))), shadow.querySelector('span'));
+ }, 'shadowRoot.elementFromPoint must return the element parent of the hit-tested text node under the point when the shadow host has display: ' + displayValue);
+});
+
+displayValues.forEach(function (displayValue) {
+ test(function () {
+ container.innerHTML = '';
+ let host = document.createElement('test-element');
+ host.style.display = displayValue;
+ let shadow = host.attachShadow({mode: 'closed'});
+ shadow.innerHTML = 'text';
+ container.appendChild(host);
+ assert_equals(shadow.elementFromPoint(...pointInElement(host)), host);
+ }, 'shadowRoot.elementFromPoint must return the shadow host when the hit-tested text node is a direct child of the root and the host has display: ' + displayValue);
+});
+
+displayValues.forEach(function (displayValue) {
+ test(function () {
+ container.innerHTML = '';
+ let host = document.createElement('test-element');
+ host.style.display = displayValue;
+ let shadow = host.attachShadow({mode: 'closed'});
+ shadow.innerHTML = '<slot></slot>';
+ host.innerHTML = 'hello';
+ container.appendChild(host);
+ assert_equals(shadow.elementFromPoint(...pointInElement(host)), shadow.querySelector('slot'));
+ }, 'shadowRoot.elementFromPoint must return the slot to which the hit-tested text node is assigned when its host has display: ' + displayValue);
+});
+
+displayValues.forEach(function (displayValue) {
+ test(function () {
+ container.innerHTML = '';
+ let host = document.createElement('test-element');
+ host.style.display = displayValue;
+ let shadow = host.attachShadow({mode: 'closed'});
+ shadow.innerHTML = '<slot></slot>';
+ host.innerHTML = '<span>hello</span>';
+ container.appendChild(host);
+ assert_equals(shadow.elementFromPoint(...pointInElement(host)), host.querySelector('span'));
+ }, 'shadowRoot.elementFromPoint must return the element parent of the hit-tested text node assigned to a slot in the shadow tree when its host has display: ' + displayValue);
+});
+
+displayValues.forEach(function (displayValue) {
+ test(function () {
+ container.innerHTML = '';
+ let host = document.createElement('test-element');
+ host.style.display = displayValue;
+ let shadow = host.attachShadow({mode: 'closed'});
+ shadow.innerHTML = '<slot></slot>';
+ host.innerHTML = '<inner-host>hello</inner-host>';
+ container.appendChild(host);
+
+ let innerHost = host.querySelector('inner-host');
+ let innerShadow = innerHost.attachShadow({mode: 'closed'});
+ innerShadow.innerHTML = '<slot></slot>';
+
+ assert_equals(shadow.elementFromPoint(...pointInElement(host)), innerHost);
+ }, 'shadowRoot.elementFromPoint must return a child element assigned to a slot'
+ + ' when the hit-tested text node is assigned to the shadow tree of the child element and the outer shadow host has display: ' + displayValue);
+});
+
+displayValues.forEach(function (displayValue) {
+ test(function () {
+ container.innerHTML = '';
+ let host = document.createElement('test-element');
+ host.style.display = displayValue;
+ let shadow = host.attachShadow({mode: 'closed'});
+ shadow.innerHTML = '<slot></slot>';
+ host.innerHTML = '<inner-host>hello</inner-host>';
+ container.appendChild(host);
+
+ let innerHost = host.querySelector('inner-host');
+ let innerShadow = innerHost.attachShadow({mode: 'closed'});
+ innerShadow.innerHTML = '<slot></slot>';
+
+ assert_equals(shadow.elementFromPoint(...pointInElement(host)), innerHost);
+ }, 'shadowRoot.elementFromPoint must return a child element assigned to a slot'
+ + ' when the hit-tested text node is assigned to a slot in the shadow tree of the child element and the outer shadow host has display: ' + displayValue);
+});
+
+displayValues.forEach(function (displayValue) {
+ test(function () {
+ container.innerHTML = '';
+ let host = document.createElement('test-element');
+ host.style.display = displayValue;
+ let shadow = host.attachShadow({mode: 'closed'});
+ shadow.innerHTML = '<slot></slot>';
+ host.innerHTML = '<inner-host></inner-host>';
+ container.appendChild(host);
+
+ let innerHost = host.querySelector('inner-host');
+ let innerShadow = innerHost.attachShadow({mode: 'closed'});
+ innerShadow.innerHTML = 'hello';
+
+ assert_equals(shadow.elementFromPoint(...pointInElement(host)), innerHost);
+ }, 'shadowRoot.elementFromPoint must return a child element with its own shadow tree assigned to a slot'
+ + ' when the hit-tested text node is its direct child and the outer shadow host has display: ' + displayValue);
+});
+
+displayValues.forEach(function (displayValue) {
+ test(function () {
+ container.innerHTML = '';
+ let host = document.createElement('test-element');
+ host.style.display = displayValue;
+ let shadow = host.attachShadow({mode: 'closed'});
+ shadow.innerHTML = '<slot></slot>';
+ host.innerHTML = '<inner-host></inner-host>';
+ container.appendChild(host);
+
+ let innerHost = host.querySelector('inner-host');
+ let innerShadow = innerHost.attachShadow({mode: 'closed'});
+ innerShadow.innerHTML = '<span>hello</span>';
+
+ assert_equals(shadow.elementFromPoint(...pointInElement(host)), innerHost);
+ }, 'shadowRoot.elementFromPoint must return a child element with its own shadow tree assigned to a slot'
+ + ' when the hit-tested text node is a child of another element and the outer shadow host has display: ' + displayValue);
+});
+
+container.innerHTML = '';
+
+</script>
+</body>
+</html>

Source/WebCore/CMakeLists.txt

@@ -391,6 +391,7 @@ set(WebCore_NON_SVG_IDL_FILES
  dom/DeviceOrientationEvent.idl
  dom/Document.idl
  dom/DocumentFragment.idl
+ dom/DocumentOrShadowRoot.idl
  dom/DocumentType.idl
  dom/Element.idl
  dom/ErrorEvent.idl

Source/WebCore/ChangeLog

@@ -1,3 +1,46 @@
+2016-10-03 Ryosuke Niwa <rniwa@webkit.org>
+
+ ShadowRoot interface should have elementFromPoint
+ https://bugs.webkit.org/show_bug.cgi?id=162882
+
+ Reviewed by Chris Dumez.
+
+ Add elementFromPoint to ShadowRoot's prototype as specified at:
+ https://www.w3.org/TR/shadow-dom/#extensions-to-the-documentorshadowroot-mixin
+ with changes proposed at https://github.com/w3c/csswg-drafts/issues/556
+
+ Added TreeScope::retargetToScope which implements 
+
+ This patch also factors DocumentOrShadowRoot.idl out of Document and ShadowRoot interfaces to better match
+ the latest DOM specification: https://dom.spec.whatwg.org/#mixin-documentorshadowroot
+
+ Test: fast/shadow-dom/Document-prototype-elementFromPoint.html
+
+ * CMakeLists.txt:
+ * DerivedSources.make:
+ * WebCore.xcodeproj/project.pbxproj:
+ * dom/Document.cpp:
+ (WebCore::Document::nodeFromPoint): Moved to TreeScope.
+ (WebCore::Document::elementFromPoint): Moved to TreeScope.
+ * dom/Document.h:
+ * dom/Document.idl: Moved elementFromPoint and activeElement to DocumentOrShadowRoot.idl.
+ * dom/DocumentOrShadowRoot.idl: Added.
+ * dom/EventPath.cpp:
+ (WebCore::RelatedNodeRetargeter::checkConsistency): Use newly added TreeScope::retargetToScope.
+ * dom/ShadowRoot.idl: Moved activeElement to DocumentOrShadowRoot.idl.
+ * dom/TreeScope.cpp:
+ (WebCore::TreeScope::retargetToScope): Added. Implements https://dom.spec.whatwg.org/#retarget efficiently.
+ Instead of checking whether A (node) is a shadow-including inclusive ancestor of B (this scope) at each
+ parent, find the lowest ancestor which contains both A and B, and return the self-inclusive ancestor of B
+ in that tree. To find the lowest common ancestor in O(n), traverse all ancestors of A and B separately and
+ do a top-down traversal. The last tree scope in which A's ancestor and B's ancestor match is the lowest
+ common ancestor.
+ (WebCore::TreeScope::nodeFromPoint): Moved from Document.
+ (WebCore::TreeScope::elementFromPoint): Moved from Document. Use retargetToScope and parentInComposedTree
+ instead of parentNode and ancestorInThisScope to match the semantics proposed in
+ https://github.com/w3c/csswg-drafts/issues/556
+ * dom/TreeScope.h:
+
 2016-10-04 Myles C. Maxfield <mmaxfield@apple.com>
 
  font-family: cursive should map to KaiTi in Chinese

Source/WebCore/DerivedSources.make

@@ -301,6 +301,7 @@ JS_BINDING_IDLS = \
  $(WebCore)/dom/DeviceOrientationEvent.idl \
  $(WebCore)/dom/Document.idl \
  $(WebCore)/dom/DocumentFragment.idl \
+ $(WebCore)/dom/DocumentOrShadowRoot.idl \
  $(WebCore)/dom/DocumentType.idl \
  $(WebCore)/dom/Element.idl \
  $(WebCore)/dom/ErrorEvent.idl \