Re: [PATCH] `completing-read` - allow history=t, sorting improvements

[Stefan Monnier]

> Btw, I attached the updated patch for the boundaries. I am not sure if the
>  approach I took there is a good one, this works only in restricted set of
>  scenarios (not with partial-completion/initials unfortunately). So this
> should be discussed.

See my comment below.

> Then you mentioned test cases - to clarify, do you want to see some kind of
> integration test where a mockup minibuffer-completion-table is set-up and
> the results of `completion-all-sorted-completions` are checked,

I think that's what we'd want, yes.

> I looked briefly into
> test/lisp/minibuffer.el - the test should probably go there?
                    ^^^
                   -tests

Yes, indeed.

> +(defun minibuffer--sort-preprocess-history (start string)
> +  "Preprocess history, remove completion prefixes.
> +STRING is the minibuffer content.
> +START is the start position of the completion."
> +  (let* ((def (car-safe minibuffer-default))
> +         (hist (symbol-value minibuffer-history-variable))
> +         (hist (if def (cons def hist) hist))
> +         (bounds (completion-boundaries
> +                  (substring string 0 (- (point) start))
> +                  minibuffer-completion-table
> +                  minibuffer-completion-predicate
> +                  ""))

Actually, the caller has the info we need already in the (cdr last),
which it throws away in:

        (when last
          (setcdr last nil)

This info also has the advantage of working with partial-completion
because it comes from the completion-style output rather than from the
completion-table.
[ If (cdr last) is nil it's equivalent to 0.  ]

> +         (pre (substring string 0 (car bounds)))
> +         (pre-len (length pre)))
> +    ;; Preprocess history if completion boundaries are used
> +    (cond
> +     ;; Special handling of file name candidates.
> +     ;; Drop prefix and everything after the first "/".
> +     (minibuffer-completing-file-name

I hope that using (cdr last) will make it unnecessary to use such a hack.
If not, then please try and use the `category` from `md` rather than
`minibuffer-completing-file-name` which I consider as obsolete (tho it's
not marked as such yet).


        Stefan