|  | <!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 { | 
|  | position: absolute; | 
|  | top: 0; | 
|  | left: 0; | 
|  | width: 150px; | 
|  | height: 200px; | 
|  | overflow: scroll; | 
|  | } | 
|  | #target1, #target2, #target3, #target4 { | 
|  | width: 100px; | 
|  | height: 100px; | 
|  | } | 
|  | #target1 { | 
|  | background-color: green; | 
|  | } | 
|  | #target2 { | 
|  | background-color: red; | 
|  | } | 
|  | #target3 { | 
|  | background-color: blue; | 
|  | } | 
|  | #target4 { | 
|  | background-color: yellow; | 
|  | } | 
|  | </style> | 
|  |  | 
|  | <div id="root"> | 
|  | <div id="target1"></div> | 
|  | <div id="target2"></div> | 
|  | <div id="target3"></div> | 
|  | </div> | 
|  |  | 
|  | <script> | 
|  | var entries = []; | 
|  | var observer; | 
|  | var target1, target2, target3, target4; | 
|  | var root; | 
|  |  | 
|  | runTestCycle(function() { | 
|  | root = document.getElementById('root'); | 
|  | target1 = document.getElementById('target1'); | 
|  | target2 = document.getElementById('target2'); | 
|  | target3 = document.getElementById('target3'); | 
|  | assert_true(!!root, "root element exists."); | 
|  | assert_true(!!target1, "target1 element exists."); | 
|  | assert_true(!!target2, "target2 element exists."); | 
|  | assert_true(!!target3, "target3 element exists."); | 
|  | observer = new IntersectionObserver(function(changes) { | 
|  | entries = entries.concat(changes); | 
|  | window.testRunner.DoNonMeasuredLayout(); | 
|  | }, { root: root }); | 
|  | observer.observe(target1); | 
|  | observer.observe(target2); | 
|  | observer.observe(target3); | 
|  | entries = entries.concat(observer.takeRecords()); | 
|  | assert_equals(entries.length, 0, "No initial notifications."); | 
|  | runTestCycle(step0, "Rects in initial notifications should report initial positions."); | 
|  | }, "isIntersecting changes should trigger notifications."); | 
|  | window.testRunner.DoNonMeasuredLayout(); | 
|  | window.testRunner.DoNonMeasuredLayout(); | 
|  |  | 
|  | function step0() { | 
|  | assert_equals(entries.length, 3, "Has 3 initial notifications."); | 
|  | checkRect(entries[0].boundingClientRect, [0, 100, 0, 100], "Check 1st entry rect"); | 
|  | assert_equals(entries[0].target.id, 'target1', "Check 1st entry target id."); | 
|  | checkIsIntersecting(entries, 0, true); | 
|  | checkRect(entries[1].boundingClientRect, [0, 100, 100, 200], "Check 2nd entry rect"); | 
|  | assert_equals(entries[1].target.id, 'target2', "Check 2nd entry target id."); | 
|  | checkIsIntersecting(entries, 1, true); | 
|  | checkRect(entries[2].boundingClientRect, [0, 100, 200, 300], "Check 3rd entry rect"); | 
|  | assert_equals(entries[2].target.id, 'target3', "Check 3rd entry target id."); | 
|  | checkIsIntersecting(entries, 2, true); | 
|  | runTestCycle(step1, "Set scrollTop=100 and check for no new notifications."); | 
|  | target1.style.marginTop = "-100px"; | 
|  | target2.style.marginTop = "-100px"; | 
|  | target3.style.marginTop = "-100px"; | 
|  | //root.scrollTop = 100; | 
|  | window.testRunner.DoNonMeasuredLayout(); | 
|  | } | 
|  |  | 
|  | function step1() { | 
|  | assert_equals(entries.length, 3, "Has 3 total notifications because isIntersecting did not change."); | 
|  | runTestCycle(step2, "Add 4th target."); | 
|  | target1.style.marginTop = "0px"; | 
|  | target2.style.marginTop = "0px"; | 
|  | target3.style.marginTop = "0px"; | 
|  | //root.scrollTop = 0; | 
|  | target4 = document.createElement('div'); | 
|  | target4.setAttribute('id', 'target4'); | 
|  | root.appendChild(target4); | 
|  | observer.observe(target4); | 
|  | } | 
|  |  | 
|  | function step2() { | 
|  | assert_equals(entries.length, 4, "Has 4 total notifications because 4th element was added."); | 
|  | checkRect(entries[3].boundingClientRect, [0, 100, 300, 400], "Check 4th entry rect"); | 
|  | assert_equals(entries[3].target.id, 'target4', "Check 4th entry target id."); | 
|  | checkIsIntersecting(entries, 3, false); | 
|  | assert_equals(entries[3].intersectionRatio, 0, 'target4 initially has intersectionRatio of 0.'); | 
|  | runTestCycle(step3, "Set scrollTop=100 and check for one new notification."); | 
|  | target1.style.marginTop = "-100px"; | 
|  | target2.style.marginTop = "-100px"; | 
|  | target3.style.marginTop = "-100px"; | 
|  | target4.style.marginTop = "-100px"; | 
|  | //root.scrollTop = 100; | 
|  | } | 
|  |  | 
|  | function step3() { | 
|  | assert_equals(entries.length, 5, "Has 5 total notifications."); | 
|  | checkRect(entries[4].boundingClientRect, [0, 100, -100, 000], "Check 5th entry rect"); | 
|  | assert_equals(entries[4].target.id, 'target4', "Check 5th entry target id."); | 
|  | checkIsIntersecting(entries, 4, true); | 
|  | assert_equals(entries[4].intersectionRatio, 0, 'target4 still has intersectionRatio of 0.'); | 
|  | root.scrollTop = 0; // reset to make it easier to refresh and run the test | 
|  | } | 
|  |  | 
|  | </script> |