|  | <!DOCTYPE html> | 
|  | <meta name="viewport" content="width=device-width,initial-scale=1"> | 
|  | <script src="/resources/testharness.js"></script> | 
|  | <script src="/resources/testharnessreport.js"></script> | 
|  | <script src="./resources/intersection-observer-test-utils.js"></script> | 
|  |  | 
|  | <style> | 
|  | pre, #log { | 
|  | position: absolute; | 
|  | top: 0; | 
|  | left: 200px; | 
|  | } | 
|  | #root { | 
|  | display: inline-block; | 
|  | overflow-y: scroll; | 
|  | height: 200px; | 
|  | border: 3px solid black; | 
|  | } | 
|  | #target { | 
|  | width: 100px; | 
|  | height: 100px; | 
|  | background-color: green; | 
|  | } | 
|  | .spacer { | 
|  | height: 300px; | 
|  | } | 
|  | </style> | 
|  |  | 
|  | <div id="root"> | 
|  | <div id="leading-space" class="spacer"></div> | 
|  | <div id="target"></div> | 
|  | <div id="trailing-space" class="spacer"</div> | 
|  | </div> | 
|  |  | 
|  | <script> | 
|  | var entries = []; | 
|  | var root, target, trailingSpace; | 
|  |  | 
|  | runTestCycle(function() { | 
|  | target = document.getElementById("target"); | 
|  | assert_true(!!target, "Target exists"); | 
|  | trailingSpace = document.getElementById("trailing-space"); | 
|  | assert_true(!!trailingSpace, "TrailingSpace exists"); | 
|  | root = document.getElementById("root"); | 
|  | assert_true(!!root, "Root exists"); | 
|  | var observer = new IntersectionObserver(function(changes) { | 
|  | entries = entries.concat(changes) | 
|  | }, {root: root}); | 
|  | observer.observe(target); | 
|  | entries = entries.concat(observer.takeRecords()); | 
|  | assert_equals(entries.length, 0, "No initial notifications."); | 
|  | runTestCycle(step0, "First rAF"); | 
|  | }, "Verify that not-intersecting notifications are sent when a target is removed from the DOM tree."); | 
|  |  | 
|  | function step0() { | 
|  | root.scrollTop = 150; | 
|  | runTestCycle(step1, "root.scrollTop = 150"); | 
|  | checkLastEntry(entries, 0, [11, 111, 311, 411, 0, 0, 0, 0, 11, 111, 11, 211, false]); | 
|  | } | 
|  |  | 
|  | function step1() { | 
|  | root.removeChild(target); | 
|  | runTestCycle(step2, "root.removeChild(target)."); | 
|  | checkLastEntry(entries, 1, [11, 111, 161, 261, 11, 111, 161, 211, 11, 111, 11, 211, true]); | 
|  | } | 
|  |  | 
|  | function step2() { | 
|  | root.scrollTop = 0; | 
|  | root.insertBefore(target, trailingSpace); | 
|  | runTestCycle(step3, "root.insertBefore(target, trailingSpace)."); | 
|  | checkLastEntry(entries, 2, [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, false]); | 
|  | } | 
|  |  | 
|  | function step3() { | 
|  | root.scrollTop = 150; | 
|  | runTestCycle(step4, "root.scrollTop = 150 after reinserting target."); | 
|  | checkLastEntry(entries, 2); | 
|  | } | 
|  |  | 
|  | function step4() { | 
|  | checkLastEntry(entries, 3, [11, 111, 161, 261, 11, 111, 161, 211, 11, 111, 11, 211, true]); | 
|  | } | 
|  | </script> |