bug#54470: 29.0.50; [PATCH] Add documentation/tests for Eshell argument expansion

[Eli Zaretskii]

> Cc: 54470@debbugs.gnu.org
> From: Jim Porter <jporterbugs@gmail.com>
> Date: Fri, 15 Apr 2022 21:57:02 -0700
> 
> On 4/15/2022 5:56 AM, Eli Zaretskii wrote:
> >> Cc: 54470@debbugs.gnu.org
> >> From: Jim Porter <jporterbugs@gmail.com>
> >> Date: Fri, 1 Apr 2022 22:10:07 -0700
> >>
> >>> @kbd is right for things that are meant specifically and only as
> >>> keyboard input.
> >>
> >> Thanks for the explanation.
> >>
> >> Having thought this over further, I think Eli's suggestion to use @samp
> >> makes sense for both the globs and the predicates/modifiers, so I've
> >> updated my patches to do this.
> > 
> > Thanks.  I was about to install these, but then I saw that some of
> > the tests you added fail on my system:
> [snip]
> 
> Thanks for testing. I think this is because `eshell-file-attributes' 
> calls `expand-file-name' on the FILE argument, which prepends a drive 
> letter on MS Windows. That makes my code in `eshell-partial-let-func' 
> (in em-pred-tests.el) fail to identify the fake files.
> 
> Can you try the attached patch to see if the tests pass? If it works, 
> I'll fold it into the previous patches and resubmit them. (It works for 
> me on an MS Windows system, but I don't have build tools on it, so I 
> just used the binary release of 28.1 with some of the bits copied from 
> my patches to test it out.)

Yes, this fixes the failures, thanks.