1020400 - "empty-cells" CSS default should be "show" in quirks mode (like in standards mode)

Status: RESOLVED FIXED

(Core :: Layout: Tables, defect)

Description

[brianhewitt1]

Attachment: behavior without empty-cells:show

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:29.0) Gecko/20100101 Firefox/29.0 (Beta/Release)
Build ID: 20140506152807

Steps to reproduce:

A table cell (class) is set to have a bottom border. There is an empty table cell.
border-bottom: 1px solid #808080;


Actual results:

unless empty-cells:show is explicitly set, the border does not show


Expected results:

CSS2 default value should be "show". It should not be necessary to set this explicitly

Comment 1

[Boris Zbarsky [:bzbarsky]]

Is your page in quirks mode, by any chance?  In quirks mode we default empty-cells to a special quirky "show background only" value.

Comment 2

[Boris Zbarsky [:bzbarsky]]

On the other hand, neither Trident (IE11) nor WebKit/Blink seem to have such a quirk.  So maybe we can remove it?

Comment 3

[brianhewitt1]

It is indeed dropped into quirks (it's an old frameset, sadly, with spotty adherence to standards). So that explains it, I suppose. 

But I'm not sure what advantage there could be of handling it differently like that. I'd be in favor of adhering to the CSS2 standard of defaulting to "show".

Comment 4

[Boris Zbarsky [:bzbarsky]]

> But I'm not sure what advantage there could be of handling it differently like that.

Yeah, I tracked this back, and it looks like we had "hide" as the default value until bug 33244 when we changed it to "hide" in quirks and "show" in standards, and then in bug 107857 changed to the current behavior.  I think we should just drop this quirk.

Comment 5

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Attachment: test of empty-cells, quirks mode

Comment 6

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Attachment: test of empty-cells, standards mode

Comment 7

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Yeah, I'm fine with removing the quirk given comment 2.  (I didn't test Trident myself on the testcases above, though.)

We should remove both the special initialization in nsStyleTableBorder::nsStyleTableBorder and nsRuleNode::ComputeTableBorderData and the -moz-show-background value itself.

Comment 8

[Boris Zbarsky [:bzbarsky]]

Attachment: Remove empty-cells quirk, since no other UA has it

Comment 9

[Cameron McCormack (:heycam)]

(In reply to David Baron [:dbaron] (UTC-8) (needinfo? for questions) from comment #7)
> Yeah, I'm fine with removing the quirk given comment 2.  (I didn't test
> Trident myself on the testcases above, though.)

IE 11 behaves the same as Chrome.

Comment 10

[Cameron McCormack (:heycam)]

Comment on attachment 8527804 [details] [diff] [review]
Remove empty-cells quirk, since no other UA has it

Review of attachment 8527804 [details] [diff] [review]:
-----------------------------------------------------------------

::: layout/style/nsStyleStruct.h
@@ +2231,5 @@
>    int32_t       mSpan;          // [reset] the number of columns spanned by a colgroup or col
>  };
>  
>  struct nsStyleTableBorder {
> +  explicit nsStyleTableBorder();

Can probably drop the explicit?

Comment 11

[Boris Zbarsky [:bzbarsky]]

Done and https://hg.mozilla.org/integration/mozilla-inbound/rev/085ff9c53ded

Comment 12

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/085ff9c53ded

Comment 13

[j.j.]

https://developer.mozilla.org/en-US/docs/Mozilla_Quirks_Mode_Behavior
needs an update

Comment 14

[Jean-Yves Perrier [:teoli]]

Doc Updated:
https://developer.mozilla.org/en-US/docs/Mozilla_Quirks_Mode_Behavior
and
https://developer.mozilla.org/en-US/Firefox/Releases/37