R devel - May 2022 - Regression in 4.2.0: unable to type special characters in Windows RGui

On 5/7/22 15:14, Cesko Voeten wrote:
> Hi,
>
> Since upgrading to 4.2.0, I can't type special characters in RGui 
> anymore. Specifically affected are at least "'~^ which, on my 
> US-International keyboard layout, all rely on dead keys. This was not 
> a problem in R <= 4.1.3, although I can't say whether the reason is 
> any change in R itself, or the fact that 4.2.0 is the first version 
> built against ucrt. OS is an up-to-date Windows 10, language is Dutch. 
> I tried toggling the 'experimental' Unicode support in
Windows's
> Country & Region settings, but it makes no difference. Is this a known 
> regression?
Thanks, could you please try the latest R-patched snapshot build and 
test it there? If there is still any problem, please report.

I've fixed handling of the dead keys in Rgui/GraphApp last week. It was 
a long standing bug (lack of support) in GraphApp Unicode windows, which 
are used when R is running in a multi-byte locale. As R 4.2 switched to 
UTF-8, this code path started to be used on systems where it wasn't 
before, but sadly this hasn't been discovered by testing before the release.

Technically, there were two bugs: one that dead keys could not be 
printed in non-combining form in principle, and another that some 
accents were not recognized. The former should be fixed fully. For the 
latter, I've added support for a number of accent keys and I can add 
more if needed (and if there is anyone who can test that).

Please test, in principle, there may be also other issues in the Unicode 
windows not reported before, and it would be nice to get these things 
fixed at least for R 4.1.

Thanks
Tomas




>
> Cesko Voeten
>
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel

Hi Tomas,

On 09-05-2022 at 10:23, Tomas Kalibera wrote:
> 
> On 5/7/22 15:14, Cesko Voeten wrote:
>> Hi,
>>
>> Since upgrading to 4.2.0, I can't type special characters in RGui
anymore. Specifically affected are at least "'~^ which, on my
US-International keyboard layout, all rely on dead keys. This was not a problem
in R <= 4.1.3, although I can't say whether the reason is any change in R
itself, or the fact that 4.2.0 is the first version built against ucrt. OS is an
up-to-date Windows 10, language is Dutch. I tried toggling the
'experimental' Unicode support in Windows's Country & Region
settings, but it makes no difference. Is this a known regression?
> 
> Thanks, could you please try the latest R-patched snapshot build and test
it there? If there is still any problem, please report.
No problem, happy to test! First of all, I'm happy to say it works and I can
type deadkey characters again, but there are some issues and discrepancies
compared to other Windows apps:

  - Some accents don't work. For instance, pressing 'a produces ?, but
pressing 'a produces 'a rather than ?. From my testing, `^~ seem to work
as expected, but '" don't.
  - Nonexistent deadkey combinations are handled differently from native
Windows. For example, typing ~^ should output ~^, but produces nothing. Typing
~^a should output ~^a, but actually yields ~?. So it seems that the first ~ is
correctly translated to the tilde symbol, but simultaneously the second ^ is
being treated as a new deadkey press, which other Windows programs don't do
in this case.
  - Related to the above two issues, '& should produce '&, while
it only gives &. This again affects only '" --- something like
^& correctly produces ^&.

Also, I'm noticing only now that selecting typed text in RGui and pressing
Ctrl deletes that text, so trying to Ctrl+C text that I typed is kind of
awkward. But this might simply be a feature that I wasn't aware of before.

Thanks for your efforts! I hope these observations help.

Cesko
> 
> I've fixed handling of the dead keys in Rgui/GraphApp last week. It was
a long standing bug (lack of support) in GraphApp Unicode windows, which are
used when R is running in a multi-byte locale. As R 4.2 switched to UTF-8, this
code path started to be used on systems where it wasn't before, but sadly
this hasn't been discovered by testing before the release.
> 
> Technically, there were two bugs: one that dead keys could not be printed
in non-combining form in principle, and another that some accents were not
recognized. The former should be fixed fully. For the latter, I've added
support for a number of accent keys and I can add more if needed (and if there
is anyone who can test that).
> 
> Please test, in principle, there may be also other issues in the Unicode
windows not reported before, and it would be nice to get these things fixed at
least for R 4.1.
> 
> Thanks
> Tomas
> 
> 
> 
> 
> 
>>
>> Cesko Voeten
>>
>> ______________________________________________
>> R-devel at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-devel