LayoutTests/editing/pasteboard/data-transfer-get-data-on-paste-rich-text.html - WebKit - Git at Google

 <!DOCTYPE html>
 <html>
 <style>
 html, body {
     margin: 0;
     font-family: -apple-system;
 }

 #source, #destination {
     width: 100%;
     margin: 0;
 }

 #destination {
     border: 1px blue green;
     height: 1024px;
 }

 #source {
     font-size: 150px;
     white-space: nowrap;
     height: 200px;
 }
 </style>
 <body>
     <div id="source">Rich text</div>
     <div id="destination" contenteditable></div>
     <pre id="output"></pre>
 </body>
 <script>

 // The contents of this `result` dictionary will contain a map of {event type => {MIME type => data}}.
 result = {};

 function updateResultWithEvent(event) {
     const eventData = {};
     for (const type of event.clipboardData.types)
         eventData[type] = event.clipboardData.getData(type).replace(/style="[^"]+"/g, 'style="...""');
     result[event.type] = eventData;
     output.textContent = JSON.stringify(result, null, "    ");
     event.preventDefault();
 }

 getSelection().setBaseAndExtent(source, 0, source, 1);
 destination.addEventListener("paste", updateResultWithEvent);

 if (window.testRunner && window.internals) {
     internals.settings.setCustomPasteboardDataEnabled(true);
     testRunner.dumpAsText();
     testRunner.execCommand("Copy");
     destination.focus();
     testRunner.execCommand("Paste");
 }
 </script>
 </html>
	<!DOCTYPE html>
	<html>
	<style>
	html, body {
	margin: 0;
	font-family: -apple-system;
	}

	#source, #destination {
	width: 100%;
	margin: 0;
	}

	#destination {
	border: 1px blue green;
	height: 1024px;
	}

	#source {
	font-size: 150px;
	white-space: nowrap;
	height: 200px;
	}
	</style>
	<body>
	<div id="source">Rich text</div>
	<div id="destination" contenteditable></div>
	<pre id="output"></pre>
	</body>
	<script>

	// The contents of this `result` dictionary will contain a map of {event type => {MIME type => data}}.
	result = {};

	function updateResultWithEvent(event) {
	const eventData = {};
	for (const type of event.clipboardData.types)
	eventData[type] = event.clipboardData.getData(type).replace(/style="[^"]+"/g, 'style="...""');
	result[event.type] = eventData;
	output.textContent = JSON.stringify(result, null, " ");
	event.preventDefault();
	}

	getSelection().setBaseAndExtent(source, 0, source, 1);
	destination.addEventListener("paste", updateResultWithEvent);

	if (window.testRunner && window.internals) {
	internals.settings.setCustomPasteboardDataEnabled(true);
	testRunner.dumpAsText();
	testRunner.execCommand("Copy");
	destination.focus();
	testRunner.execCommand("Paste");
	}
	</script>
	</html>