Implement elementsFromPoint

LayoutTests/fast/dom/elementsFromPoint/resources/elementsFromPoint.js

Index: LayoutTests/fast/dom/elementsFromPoint/resources/elementsFromPoint.js
diff --git a/LayoutTests/fast/dom/elementsFromPoint/resources/elementsFromPoint.js b/LayoutTests/fast/dom/elementsFromPoint/resources/elementsFromPoint.js
new file mode 100644
index 0000000000000000000000000000000000000000..e1b92e53c9956e21059ce831a5c4c07d930603ec
--- /dev/null
+++ b/LayoutTests/fast/dom/elementsFromPoint/resources/elementsFromPoint.js
@@ -0,0 +1,88 @@
+function nodeToString(node) {
+  var str = '';
+  if (node.nodeType == Node.ELEMENT_NODE) {
+    str += node.nodeName;
+    if (node.id)
+      str += '#' + node.id;
+    else if (node.class)
+      str += '.' + node.class;
+  } else if (node.nodeType == Node.TEXT_NODE) {
+    str += '\'' + node.data + '\'';
+  } else if (node.nodeType == Node.DOCUMENT_NODE) {
+    str += '#document';
+  }
+  return str;
+}
+
+function nodeListToString(nodes) {
+  var nodeString = '';
+
+  for (var i = 0; i < nodes.length; i++) {
+    var str = nodeToString(nodes[i]);
+    if (!str)
+      continue;
+    nodeString += str;
+    if (i + 1 < nodes.length)
+      nodeString += ', ';
+  }
+  return nodeString;
+}
+
+function assertElementsFromPoint(actual, expected) {
+  shouldBeEqualToString('nodeListToString(' + actual + ')', nodeListToString(expected));
+}
+
+function assertElementInSequence(sequence, value, expectedInSequence) {
+  if (expectedInSequence)
+    shouldBeGreaterThanOrEqual(sequence + '.indexOf(' + value + ')', '0');
+  else
+    shouldBeEqualToNumber(sequence + '.indexOf(' + value + ')', -1);
+}
+
+function checkElementsFromPointFourCorners(doc, evalElement) {
+  var element = eval(evalElement);
+  var shouldReceivePointerEvents = window.getComputedStyle(element).pointerEvents != 'none';
+  var rect = element.getBoundingClientRect();
+
+  var topLeft = {x: rect.left + 1, y: rect.top + 1};
+  var topRight = {x: rect.right - 1, y: rect.top + 1};
+  var bottomLeft = {x: rect.left + 1, y: rect.bottom - 1};
+  var bottomRight = {x: rect.right - 1, y: rect.bottom - 1};
+
+  var topLeftElements = doc + '.elementsFromPoint(' + topLeft.x + ', ' + topLeft.y + ')';
+  var topRightElements = doc + '.elementsFromPoint(' + topRight.x + ', ' + topRight.y + ')';
+  var bottomLeftElements = doc + '.elementsFromPoint(' + bottomLeft.x + ', ' + bottomLeft.y + ')';
+  var bottomRightElements = doc + '.elementsFromPoint(' + bottomRight.x + ', ' + bottomRight.y + ')';
+
+  assertElementInSequence(topLeftElements, evalElement, shouldReceivePointerEvents);
+  assertAllElementsIntersectPoint(topLeftElements, topLeft);
+  assertElementInSequence(topRightElements, evalElement, shouldReceivePointerEvents);
+  assertAllElementsIntersectPoint(topRightElements, topRight);
+  assertElementInSequence(bottomLeftElements, evalElement, shouldReceivePointerEvents);
+  assertAllElementsIntersectPoint(bottomLeftElements, bottomLeft);
+  assertElementInSequence(bottomRightElements, evalElement, shouldReceivePointerEvents);
+  assertAllElementsIntersectPoint(bottomRightElements, bottomRight);
+}
+
+function assertAllElementsIntersectPoint(sequence, point) {
+  var elementsEv;
+  try {
+    elementsEv = eval(sequence);
+  } catch (e) {
+    testFailed('Evaluating ' + sequence + ': Threw exception ' + e);
+    return;
+  }
+
+  var numElements = elementsEv.length;
+  for (var i = 0; i < numElements; i++) {
+    var clientRect = elementsEv[i].getBoundingClientRect();
+    if (point.x < clientRect.left
+        || point.x > clientRect.right
+        || point.y < clientRect.top
+        || point.y > clientRect.bottom) {
+      testFailed(sequence + '[' + i + '].getBoundingClientRect() does not intersect (' + point.x + ', ' + point.y + ')');
+      return;
+    }
+  }
+  testPassed('All elements in ' + sequence + ' intersect (' + point.x + ', ' + point.y + ')');
+}