bug#45576: 28.0.50 [native-comp] some functions in eshell stop functioning after commit 0593f478762437e2a8618f3f874a26424e4590b4

[address@hidden]

Hi Andrea,
I can confirm that commit #     43d0e8483e5b51aec1347b8a2ed53acae34a9811  
solves the issue.

Thanks,
Kiong-Ge.

‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐

On Saturday, January 2nd, 2021 at 6:11 AM, Andrea Corallo <akrl@sdf.org> wrote:

> Andrea Corallo via "Bug reports for GNU Emacs, the Swiss army knife of
>
> text editors" bug-gnu-emacs@gnu.org writes:
>
> > "gliao.tw@pm.me" gliao.tw@pm.me writes:
> >
> > > Hi,
> > >
> > > More precisely, in this case, the "eshell-find-alias-function" definded 
> > > in $EMACS_DIR/share/emacs/28.0.50/lisp/eshell/esh-cmd.el.gz seems where 
> > > the issue pops up.
> > >
> > > Before commit #0593f478762437e2a8618f3f874a26424e4590b4,
> > >
> > > (eshell-find-alias-function "ls") shows
> > >
> > > "eshell/ls"
> > >
> > > but on or after commit #0593f478762437e2a8618f3f874a26424e4590b4, the 
> > > same command shows
> > >
> > > "nil"
> > >
> > > Both cases are based on functions loaded from eshell.el.gz and 
> > > esh-cmd.el's corresponding eln files.
> > >
> > > It seems that some part of the type inference code added recently lead to 
> > > this unexpected result.
> > >
> > > Thanks,
> > >
> > > Kiong-Ge.
> >
> > I see what's going, this is very funny :)
> >
> > I've used the alist producing `cl-deftype-satisfies' and reversed it to
> >
> > get the relation type-predicate -> type.
> >
> > But doing this way satisfying `functionp' implies the argument being a
> >
> > function (while indeed it can be also a symbol).
> >
> > Using this information the compiler cleverly proves the output of
> >
> > `eshell-find-alias-function' being always nil.
> >
> > So I guess the relation type <-> predicate in the alist used to build
> >
> > `cl-deftype-satisfies' is correct but not bijective and cannot simply be
> >
> > reversed to produce what I use.
> >
> > I'll come up with a fix tomorrow.
>
> Right 43d0e8483e fix it for me, could you give a try?
>
> Thanks!
>
> Andrea