1407167 - aria ROLE values are case sensitive

Status: RESOLVED FIXED

(Core :: Disability Access APIs, defect, P5)

Description

[steve faulkner]

Go to https://s.codepen.io/stevef/debug/YrLwwE
check the role name exposed in Ia2 for the first role="BUTton".
should be 'push button' actual is text frame.

IE/Edge/Safari treat role values as ASCII case insensitive, firefox does not.
Suggest that firefox should.

Comment 1

[Marco Zehe (:MarcoZ)]

OUCH! This is a really silly bug, since all other attribute values in HTML are of course case-insensitive, too. Alex, where is this being checked? We need to fix this ASAP.

Comment 2

[alexander :surkov (:asurkov)]

Core AAM seems to agree as HTML is case-insensitive language, C item states [1]:

"Do a comparison of the substrings to all the names of the non-abstract WAI-ARIA roles. Case-sensitivity of the comparison inherits from the case-sensitivity of the host language."

Marco, what does it make you think this is a high priority bug? It rather feels as an edge case that'd be good to handle. I'm assigning it to p5 for the first pass, but please feel free to bump it.

Also I'm not sure whether there's a point of ARIA to inherit case-sensitivity rules from a host language. We probably should ask ARIA group for clarification before jumping into fixing the bug.

https://www.w3.org/TR/core-aam-1.1/#roleMappingGeneralRules

Comment 3

[Firefox Bug Husbandry Bot]

See bug 1547409. Moving webcompat whiteboard tags to project flags.

Comment 4

[marcos]

Just noting that Chrome and Safari treat the assigning the roles as case insensitive, so this/remains is a potential web combat issue.

Comment 5

[marcos]

I think https://searchfox.org/mozilla-central/source/accessible/base/ARIAMap.cpp#1383 is what needs to change... the comparator is case sensitive there. Either the constructor should lcase mRole or maybe there is some Compare() function that can do the case comparison. I couldn't work out what namespace Compare() is being called from (and neither could searchfox), so I could figure out what a quick fix might be.

Does anyone know? If someone can guide me I can try to fix this.

Comment 6

[James Teh [:Jamie]]

Yuck. I think we're using this non-namespaced Compare function. I don't even understand why that exists.

I would just change that line to this (I haven't tested though):

return mRole.Compare(aEntry.ARIARoleString(), /* aIgnoreCase */ true);

Note that while this bug is (currently) just about ARIA roles, there are quite a few other places where ARIA attribute values are expected to be lower case; true, false, etc. That should mostly be a matter of changing instances of eCaseMatters to eIgnoreCase, but there may be some which shouldn't be changed, so each will need to be examined.

Comment 7

[marcos]

(In reply to James Teh [:Jamie] from comment #6)

return mRole.Compare(aEntry.ARIARoleString(), /* aIgnoreCase */ true);

Hehe, I actually tried that yesterday. For whatever reason, the nsDependentSubstring class doesn't have a .Compare() method. That's where I got stuck... Gecko strings are always a bit of a challenge.

Note that while this bug is (currently) just about ARIA roles, there are quite a few other places where ARIA attribute values are expected to be lower case; true, false, etc. That should mostly be a matter of changing instances of eCaseMatters to eIgnoreCase, but there may be some which shouldn't be changed, so each will need to be examined.

Yeah, absolutely.

Comment 8

[James Teh [:Jamie]]

Blah. Maybe this?

#include "nsUnicharUtils.h"
...
return Compare(mRole, aEntry.ARIARoleString(), nsCaseInsensitiveStringComparator);

Comment 9

[marcos]

Nice one, Jamie! Worked a treat! I'll hunt around for tests and draft up a patch.

Comment 10

[James Teh [:Jamie]]

accessible/tests/mochitest/role/aria.html is probably a reasonable place for role tests.

Comment 11

[marcos]

Attachment: Make ARIA in HTML mapping case insensitive

Comment 12

[marcos]

Try:
https://treeherder.mozilla.org/jobs?repo=try&revision=10e250c63f8065d6aaacd8d7edc6233145ae6f1f

Comment 13

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/da103fff9e7e
Make ARIA in HTML mapping case insensitive r=Jamie

Comment 14

[Cristian Brindusan [:cbrindusan]]

https://hg.mozilla.org/mozilla-central/rev/da103fff9e7e