- From: Emilio Cobos Álvarez via GitHub <sysbot+gh@w3.org>
- Date: Thu, 01 Aug 2019 20:06:23 +0000
- To: public-css-archive@w3.org
This bit me while trying to implement an optimization in Firefox. Firefox returns what I think is the correct value in these test-cases:
<details>
```html
<!doctype html>
<style>
.parent {
width: 200px;
height: 200px;
background: purple;
}
.child {
width: 10px;
height: 10px;
background: yellow;
}
.fixed-margins-b {
margin-left: 10px;
margin-right: 60px;
}
.fixed-margins-a {
margin-right: 10px;
margin-left: 60px;
}
.percent-margins-a {
margin-right: 10px;
margin-left: 30%;
}
.percent-margins-b {
margin-left: 10px;
margin-right: 30%;
}
.percent-margins-c {
margin-right: 5%;
margin-left: 30%;
}
.percent-margins-d {
margin-left: 5%;
margin-right: 30%;
}
</style>
<div class="parent">
<div class="child fixed-margins-a"></div>
</div>
<div class="parent">
<div class="child fixed-margins-b"></div>
</div>
<div class="parent">
<div class="child percent-margins-a"></div>
</div>
<div class="parent">
<div class="child percent-margins-b"></div>
</div>
<div class="parent">
<div class="child percent-margins-c"></div>
</div>
<div class="parent">
<div class="child percent-margins-d"></div>
</div>
<pre>
<script>
for (let element of document.querySelectorAll(".child")) {
let cs = getComputedStyle(element);
document.writeln(element.className + ": " + cs.marginLeft + " | " + cs.marginRight);
}
</script>
</pre>
```
</details>
One WPT relies on us _not_ doing this, and returning the pixel value as-is. My patch "fixed" the WPT, but given this issue I think I'm going to keep our behavior untouched for now, and reference this issue from the code. Also maybe fix the WPT, which is a rather naive one that isn't testing this in particular (
--
GitHub Notification of comment by emilio
Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/2328#issuecomment-517437931 using your GitHub account
Received on Thursday, 1 August 2019 20:06:29 UTC