Re: [PATCH] `completion-all-sorted-completions`: Add support for completion boundaries

[Stefan Monnier]

> I attached a patch which adds support for completion boundaries to the
> sorting by history position. Tests are included.

Thanks, pushed.

> lisp/minibuffer.el (completion-all-sorted-completions): The history is
> preprocessed by the function `minibuffer--sort-preprocess-history`.
> The default value is prepended to the history.  The completion base
> prefix string is removed from the history elements.  This allows
> sorting by history position for completion tables which use completion
> boundaries, in particular the file completion table.
> test/lisp/minibuffer-tests.el (completion-all-sorted-completions): Add
> tests for various combinations of with/without history/base/default.

I massaged this to use the active voice and stick a bit closer to
our conventions.

> +(defun minibuffer--sort-preprocess-history (base)
> +  "Preprocess history.
> +Remove completion BASE prefix string from history elements."
> +  (let* ((def (if (stringp minibuffer-default)
> +                  minibuffer-default
> +                (car-safe minibuffer-default)))
> +         (hist (and (not (eq minibuffer-history-variable t))
> +                    (symbol-value minibuffer-history-variable)))
> +         (base-size (length base)))
> +    ;; Drop base string from the history elements
> +    (when (/= base-size 0)
> +      (setq hist (delq nil (mapcar
> +                            (lambda (c)
> +                              (when (string-prefix-p base c)
> +                                (substring c base-size)))
> +                            hist))))
> +    ;; Default comes first
> +    (setq hist (if def (cons def hist) hist))
> +    hist))

I massaged this so that `def` is also filtered through `base`
(and also so that comments are properly punctuated).

> +                 (`(boundaries . ,_) `(boundaries ,(length base) . 0))
> +                 (_ (complete-with-action action
> +                                          '(epsilon alpha gamma beta delta)

And I changed this completion table to a list of strings, since lists of
symbols happen to work most of the time but aren't officially supported
(we support alists whose keys are symbols, OTOH).


        Stefan