_files -g <pattern> offers files that don't match the pattern and conversely

_files -g <pattern> offers files that don't match the pattern and conversely

[Johan Grande]

Are these bugs or am I misunderstanding how the -g option works?

With zsh 5.8.1 (x86_64-ubuntu-linux-gnu) and an empty .zshrc.

% ls
a  b

% _f() { _files -g 'c(.)' }; compdef _f f
% f <tab>
a  b       # even though 'a' and 'b' don't match the pattern

However,

% _f() { _path_files -g 'c(.)' }; compdef _f f
% f <tab>  # nothing

Conversely,

% _f() { _files -g '^(a #)(.)' }; compdef _f f
% f <tab>  # nothing, even though 'b' matches the pattern

However,

% _f() { _path_files -g '^(a #)(.)' }; compdef _f f
% f <tab>  # becomes
% f b

Also, and this is the same for _files and _path_files:

% f() { echo $@ }
% _f() { _files -g 'c' }; compdef _f f
% f <tab>  # becomes
% f c      # even though there is no such file

-- 
Johan Grande

Re: _files -g <pattern> offers files that don't match the pattern and conversely

[Johan Grande]

Apologies, this line should go at the top:

> % f() { echo $@ }

Re: _files -g <pattern> offers files that don't match the pattern and conversely

[Bart Schaefer]

On Sat, Jul 15, 2023 at 6:32 AM Johan Grande <nahoj@crans.org> wrote:
>
> % _f() { _files -g 'c(.)' }; compdef _f f
> % f <tab>
> a  b       # even though 'a' and 'b' don't match the pattern

The only way I can make this happen is if "a" and "b" are directories.
_files will complete local directory names if there are no matching
files.

> % _f() { _path_files -g 'c(.)' }; compdef _f f
> % f <tab>  # nothing

_path_files expects the pattern to match directories too.

> % _f() { _files -g '^(a #)(.)' }; compdef _f f
> % f <tab>  # nothing, even though 'b' matches the pattern

The space in the pattern needs to be quoted, it's being taken as a
word separator.

_f() { _files -g '^(a\ #)(.)' }

I haven't investigated possible fixes.

> % _f() { _path_files -g '^(a #)(.)' }; compdef _f f
> % f <tab>  # becomes
> % f b

Unlike _files, _path_files is applying the pattern directly and
doesn't have a problem with the space.

> Also, and this is the same for _files and _path_files:
>
> % f() { echo $@ }
> % _f() { _files -g 'c' }; compdef _f f
> % f <tab>  # becomes
> % f c      # even though there is no such file

There's only one possible completion, so it's offered.

Re: _files -g <pattern> offers files that don't match the pattern and conversely

[Johan Grande]

Le 15/07/2023 à 18:16, Bart Schaefer a écrit :
> On Sat, Jul 15, 2023 at 6:32 AM Johan Grande <nahoj@crans.org> wrote:
>>
>> % _f() { _files -g 'c(.)' }; compdef _f f
>> % f <tab>
>> a  b       # even though 'a' and 'b' don't match the pattern
> 
> The only way I can make this happen is if "a" and "b" are directories.
> _files will complete local directory names if there are no matching
> files.

In my test they are regular files, but the problem disappears if I 
replace /usr/share/zsh/functions/Completion/ with that of zsh 5.9, so it 
seems that this one was fixed.

>> [...]
>> % _f() { _files -g 'c' }; compdef _f f
>> % f <tab>  # becomes
>> % f c      # even though there is no such file
> 
> There's only one possible completion, so it's offered.
> 
OK, thank you.

-- 
Johan

Re: _files -g <pattern> offers files that don't match the pattern and conversely

[Bart Schaefer]

On Sat, Jul 15, 2023 at 9:51 AM Johan Grande <nahoj@crans.org> wrote:
>
> Le 15/07/2023 à 18:16, Bart Schaefer a écrit :
> > On Sat, Jul 15, 2023 at 6:32 AM Johan Grande <nahoj@crans.org> wrote:
> >>
> >> % _f() { _files -g 'c(.)' }; compdef _f f
> >> % f <tab>
> >> a  b       # even though 'a' and 'b' don't match the pattern
> >
> > The only way I can make this happen is if "a" and "b" are directories.
> > _files will complete local directory names if there are no matching
> > files.
>
> In my test they are regular files

Hmm.  OK, I can now reproduce this with both 5.8 and 5.9 _files but
only if there are no local directories either (e.g., with "a" "b" and
"d/" I get "d" only).

So the real reason here is that _files always tries the "directories"
and "all-files" tags if "globbed-files" doesn't find anything.
_path_files does not use the same tags list.