bash 5.2.21-1: a bug in [0-9] expansion

[Duncan Roe]

On Fri, Sep 05, 2025 at 12:39:58PM +1000, cygwin wrote:
> On Sun, Aug 31, 2025 at 12:06:09PM -0700, cygwin wrote:
> > Description of the problem.
> > [0-9]  picks also certain Unicode superscript characters ( namely, ⁰ ⁴ ⁵ ⁶
> > ⁷ ⁸ ⁹ ), and every Unicode subscript character.
> > 
> > Example: the directory has the following files:
> > $ /bin/ls
> > ₀.txt  ₁.txt  ₂.txt  ₃.txt  ₄.txt  ₅.txt  ₆.txt  ₇.txt  ₈.txt  ₉.txt
> > ⁰.txt  ¹.txt  ².txt  ³.txt  ⁴.txt  ⁵.txt  ⁶.txt  ⁷.txt  ⁸.txt  ⁹.txt
> > 
> > $ /bin/ls [0-9].txt
> > ₀.txt  ₁.txt  ₃.txt  ⁴.txt  ⁵.txt  ⁶.txt  ⁷.txt  ⁸.txt
> > ⁰.txt  ₂.txt  ₄.txt  ₅.txt  ₆.txt  ₇.txt  ₈.txt
> > 
> > $ locale
> > LANG=en_US.UTF-8
> > LC_CTYPE="en_US.UTF-8"
> > LC_NUMERIC="en_US.UTF-8"
> > LC_TIME="en_US.UTF-8"
> > LC_COLLATE="en_US.UTF-8"
> > LC_MONETARY="en_US.UTF-8"
> > LC_MESSAGES="en_US.UTF-8"
> > LC_ALL=
> > 
> > System.
> > Fully up to date Windows 11
> > cygwin 3.6.4-1
> > bash    5.2.21-1
> > 
> This reproduces under Linux with the newest available bash versions.
> 
> Rather than post the gory details of what I think is the underlying cause,
> I'll report it as a bash issue and post a link to the report.
> 
Link is https://lists.gnu.org/archive/html/bug-bash/2025-09/msg00053.html

Cheers ... Duncan.