1368651 - stylo: @import rule objects sometimes may fail to be constructed

Status: RESOLVED FIXED

(Core :: CSS Parsing and Computation, enhancement, P2)

Description

[Xidorn Quan [:xidorn] UTC+10]

In bug 1352968 part 8, we try to construct CSSOM object for @import rules when possible. But there are cases that we cannot construct the object correctly, those cases include:
1. when the stylesheet is a clone, its child sheet list may not be rebuilt correctly (bug 1367213)
2. when the newly inserted child sheet is a clone from an existing sheet, but the Servo side @import rule struct is holding an independent stylesheet (bug 1368381)

When those bugs are fixed, we should be able to always return non-null object for @import rule, and also change several warnings added in bug 1352968 to assertions.

Comment 1

[Manish Goregaokar [:manishearth]]

I'm not getting a properly constructed import rule in this simple case, either. Not sure if it's the same bug:

<style type='text/css'> @import url('foo.css') </style>
<script type="text/javascript">document.write(document.styleSheets[0].cssRules[0])</script>

(It prints null in Stylo)

Comment 2

[Xidorn Quan [:xidorn] UTC+10]

(In reply to Manish Goregaokar [:manishearth] from comment #1)
> I'm not getting a properly constructed import rule in this simple case,
> either. Not sure if it's the same bug:
> 
> <style type='text/css'> @import url('foo.css') </style>
> <script
> type="text/javascript">document.write(document.styleSheets[0].cssRules[0])</
> script>
> 
> (It prints null in Stylo)

This is a new bug unrelated to existing two. Thanks for mentioning. Filed bug 1371488 and submitted patch there.

Comment 3

[Xidorn Quan [:xidorn] UTC+10]

This should be all be fixed by emilio's patch in bug 1372041.