LayoutTests/accessibility/dynamically-ignored-canvas.html - external/github.com/WebKit/webkit - Git at Google

 <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN">
 <html>
 <head>
 <script src="../resources/accessibility-helper.js"></script>
 <script src="../resources/js-test.js"></script>
 </head>
 <body>

 <!--
   This test fails on ITM because we have a bug where the AXObjectCache never receives a children changed notification
   for the <canvas> element, despite the fact all of its children are removed. One place we could start sending those
   notifications is in ContainerNode::childrenChanged. I briefly experimented with this and it did fix this test in ITM,
   but to confidently make that change we need to investigate more.

   For example, that function is very hot, so we need to make sure hooking into it doesn't kill performance.
   There may also be better candidates for getting these updates.
 -->

 <div id="group" role="group">
     <canvas id="canvas"><div>I am some text inside a div, which is inside a canvas</div></canvas>
 </div>

 <script>
     // This test uses a <canvas> to dynamically change ignored status, but the goal is to ensure that any element
     // that changes ignored status dynamically results in that element's parent getting a childrenChanged call. Then the
     // AX tree should be updated appropriately, either removing or adding the ignored or un-ignored element respectively.
     var testOutput = "This test ensures that we properly change an object's ignored status after dynamically changing the page.\n\n";

     function isIgnored(id) {
         const axElement = accessibilityController.accessibleElementById(id);
         if (!axElement)
             return true;
         return axElement.isIgnored;
     }

     function addTreeToOutput(axElement, indent = 0) {
         if (!axElement)
             return;

         let indentStr = "";
         for (let i = 0; i < indent; i++)
             indentStr += "  ";

         for (let i = 0; i < axElement.childrenCount; i++) {
             const child = axElement.childAtIndex(i);
             testOutput += `${indentStr}${child.role}`;
             if (child.role && child.role.includes("StaticText"))
                 testOutput += ` ${accessibilityController.platformName === "ios" ? child.description : child.stringValue}`;
             testOutput += "\n";
             addTreeToOutput(child, indent + 1);
         }
     }

     function addGroupTreeToOutput() {
         const group = accessibilityController.accessibleElementById("group");
         addTreeToOutput(group);
         testOutput += "\n";
     }

     if (window.accessibilityController) {
         window.jsTestIsAsync = true;

         testOutput += `#canvas is initially ignored: ${isIgnored("canvas")}\n`;
         testOutput += "Dumping AX tree starting at #group.\n";
         addGroupTreeToOutput();

         testOutput += `Removing all children of #canvas.\n`;
         const canvasElement = document.getElementById("canvas");
         while (canvasElement.firstChild) { canvasElement.removeChild(canvasElement.firstChild); }
         setTimeout(async function() {
             await waitFor(() => {
                 const axCanvas = accessibilityController.accessibleElementById("canvas");
                 return !axCanvas || !axCanvas.childrenCount;
             });
             testOutput += `#canvas is ignored: ${isIgnored("canvas")}\n`;
             // Removing the <canvas> fallback content makes it ignored, so the canvas should send a notification to its parent
             // that it needs to update its children.
             testOutput += "Dumping AX tree starting at #group.\n";
             addGroupTreeToOutput();

             debug(testOutput);
             finishJSTest();
         }, 0);
     }
 </script>
 </body>
 </html>
	<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN">
	<html>
	<head>
	<script src="../resources/accessibility-helper.js"></script>
	<script src="../resources/js-test.js"></script>
	</head>
	<body>

	<!--
	This test fails on ITM because we have a bug where the AXObjectCache never receives a children changed notification
	for the <canvas> element, despite the fact all of its children are removed. One place we could start sending those
	notifications is in ContainerNode::childrenChanged. I briefly experimented with this and it did fix this test in ITM,
	but to confidently make that change we need to investigate more.

	For example, that function is very hot, so we need to make sure hooking into it doesn't kill performance.
	There may also be better candidates for getting these updates.
	-->

	<div id="group" role="group">
	<canvas id="canvas"><div>I am some text inside a div, which is inside a canvas</div></canvas>
	</div>

	<script>
	// This test uses a <canvas> to dynamically change ignored status, but the goal is to ensure that any element
	// that changes ignored status dynamically results in that element's parent getting a childrenChanged call. Then the
	// AX tree should be updated appropriately, either removing or adding the ignored or un-ignored element respectively.
	var testOutput = "This test ensures that we properly change an object's ignored status after dynamically changing the page.\n\n";

	function isIgnored(id) {
	const axElement = accessibilityController.accessibleElementById(id);
	if (!axElement)
	return true;
	return axElement.isIgnored;
	}

	function addTreeToOutput(axElement, indent = 0) {
	if (!axElement)
	return;

	let indentStr = "";
	for (let i = 0; i < indent; i++)
	indentStr += " ";

	for (let i = 0; i < axElement.childrenCount; i++) {
	const child = axElement.childAtIndex(i);
	testOutput += `${indentStr}${child.role}`;
	if (child.role && child.role.includes("StaticText"))
	testOutput += ` ${accessibilityController.platformName === "ios" ? child.description : child.stringValue}`;
	testOutput += "\n";
	addTreeToOutput(child, indent + 1);
	}
	}

	function addGroupTreeToOutput() {
	const group = accessibilityController.accessibleElementById("group");
	addTreeToOutput(group);
	testOutput += "\n";
	}

	if (window.accessibilityController) {
	window.jsTestIsAsync = true;

	testOutput += `#canvas is initially ignored: ${isIgnored("canvas")}\n`;
	testOutput += "Dumping AX tree starting at #group.\n";
	addGroupTreeToOutput();

	testOutput += `Removing all children of #canvas.\n`;
	const canvasElement = document.getElementById("canvas");
	while (canvasElement.firstChild) { canvasElement.removeChild(canvasElement.firstChild); }
	setTimeout(async function() {
	await waitFor(() => {
	const axCanvas = accessibilityController.accessibleElementById("canvas");
	return !axCanvas \|\| !axCanvas.childrenCount;
	});
	testOutput += `#canvas is ignored: ${isIgnored("canvas")}\n`;
	// Removing the <canvas> fallback content makes it ignored, so the canvas should send a notification to its parent
	// that it needs to update its children.
	testOutput += "Dumping AX tree starting at #group.\n";
	addGroupTreeToOutput();

	debug(testOutput);
	finishJSTest();
	}, 0);
	}
	</script>
	</body>
	</html>