Another tab completion bug? Matching text with different case where input is a prefix of some file

[razzius]

It completes a file when there are multiple options, then goes into the tab completion selection UI:

tab-completion $ fish --version
fish, version 4.4.0
tab-completion $ ls
read_twice.c  README.md
tab-completion $ vim r<TAB>
# this adds read_twice.c and then goes into the tab competion selector
# it looks like this:
tab-completion $ vim read_twice.c README.md
…d_twice.c  README.md
# all after hitting only 1 key

[razzius]

Oof hit a particularly scary invocation by mistake:

Downloads $ remove github-recovery-codes.txt Git-2.52.0-64-bit.exe 

rm<space>g<tab><enter>

[razzius]

I tried this with no fish config and still got the tab completion bug, will raise upstream

[razzius]

Ok this is not a bug per se - if the input is a prefix of one of the files, it'll just complete, even if it's a substring of another. Then hitting tab again will list all the files, and I'll get the UI I experienced before.

[razzius]

(I found this to still be occurring with fish 3.7.1)

[razzius]

To frame this another way, fish is treating prefixes of mixed case as unambiguously the same-case prefix. Something like:

it'll just complete, even if it's a substring of another or same text with different case in any position

[razzius]

This is also open upstream as fish-shell/fish-shell#7803