1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
|
<!DOCTYPE html>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<style>
#scroller {
height: 200px;
width: 200px;
overflow: scroll;
}
#a1, #space1, #a2, #space2 {
height: 200px;
}
#a1, #a2 {
background-color: #8f8;
}
</style>
<div id="scroller">
<div id="space0"></div>
<div id="a1"></div>
<div id="space1"></div>
<div id="a2"></div>
<div id="space2"></div>
</div>
<script>
// Tests that the anchor node is recomputed after an explicit change to the
// scroll position.
test(() => {
var scroller = document.querySelector("#scroller");
scroller.scrollTop = 500;
// We should now be anchored to #a2.
document.querySelector("#space1").style.height = "300px";
assert_equals(scroller.scrollTop, 600);
scroller.scrollTop = 100;
// We should now be anchored to #a1. Make sure there is no adjustment from
// moving #a2.
document.querySelector("#space1").style.height = "400px";
assert_equals(scroller.scrollTop, 100);
// Moving #a1 should produce an adjustment.
document.querySelector("#space0").style.height = "100px";
assert_equals(scroller.scrollTop, 200);
}, "Anchor node recomputed after an explicit scroll occurs.");
</script>
|
