Support Vertico sorting functions

[olnw]

Closes #18

This commit makes hotfuzz aware of vertico-sort-override-function and vertico-sort-function. This allows candidates to be sorted by minibuffer history, such as with Vertico's default sorting function, vertico-sort-history-length-alpha.

[axelf4]

Thanks! This can get messy, however, if it is to also use corfu--sort-function if Corfu is the active UI, etc.

@minad Could Vertico instead alter the metadata it passes to completion-all-completions such that display-sort-function is set to (vertico--sort-function)? That way, the hotfuzz/flex/... completion--adjust-metadata functions should just do the right thing.

[olnw]

Upon investigating this a bit further, I found a bug report for fido-mode wherein it was not sorting candidates by their history positions,¹ and the corresponding fix.² This was solved in flex's metadata adjustment function by only specifying a display-sort-function when the prompt was non-empty, thereby allowing icomplete to handle sorting.

hotfuzz could do something similar:

diff --git a/hotfuzz.el b/hotfuzz.el
index 50ceaa5..9fe2e08 100644
--- a/hotfuzz.el
+++ b/hotfuzz.el
@@ -167,7 +167,8 @@ will lead to inaccuracies."
 (defun hotfuzz--adjust-metadata (metadata)
   "Adjust completion METADATA for hotfuzz sorting."
   (let ((existing-dsf (completion-metadata-get metadata 'display-sort-function))
-        (existing-csf (completion-metadata-get metadata 'cycle-sort-function)))
+        (existing-csf (completion-metadata-get metadata 'cycle-sort-function))
+        (filtering-p (or (not (minibufferp)) (> (point-max) (minibuffer-prompt-end)))))
     (cl-flet ((compose-sort-fn (existing-sort-fn)
                 (lambda (completions)
                   (if (or (null completions)
@@ -175,8 +176,9 @@ will lead to inaccuracies."
                       completions
                     (funcall existing-sort-fn completions)))))
       `(metadata
-        (display-sort-function . ,(compose-sort-fn (or existing-dsf #'identity)))
-        (cycle-sort-function . ,(compose-sort-fn (or existing-csf #'identity)))
+        ,@(when filtering-p
+            `((display-sort-function . ,(compose-sort-fn (or existing-dsf #'identity)))
+              (cycle-sort-function . ,(compose-sort-fn (or existing-csf #'identity)))))
         . ,(cdr metadata)))))
 
 ;;;###autoload

However, as João commented, this was not optimal:

(let ((flex-is-filtering-p
         ;; JT@2019-12-23: FIXME: this is kinda wrong.  What we need
         ;; to test here is "some input that actually leads/led to
         ;; flex filtering", not "something after the minibuffer
         ;; prompt".  E.g. The latter is always true for file
         ;; searches, meaning we'll be doing extra work when we
         ;; needn't.
         (or (not (window-minibuffer-p))
             (> (point-max) (minibuffer-prompt-end))))

The solution was later updated to check that completion-pcm--regexp was non-nil, which is a variable set by completion-pcm--hilit-commonality, which is called by completion-flex-all-completions.³

1. https://lists.gnu.org/archive/html/emacs-bug-tracker/2021-08/msg00321.html
2. emacs-mirror/emacs@2c699b8
3. emacs-mirror/emacs@dfffb91#diff-9fe92bd4449f8efe346fc61ec3ba7e772b1d500ea79254dac58b040a9d1f688bR4324

[axelf4]

Perhaps something like:

diff --git a/hotfuzz.el b/hotfuzz.el
index 50ceaa5..c90cd15 100644
--- a/hotfuzz.el
+++ b/hotfuzz.el
@@ -43,6 +43,8 @@ Large values will decrease performance."
 (defvar hotfuzz--d (make-vector hotfuzz--max-needle-len 0))
 (defvar hotfuzz--bonus (make-vector hotfuzz--max-haystack-len 0))
 
+(defvar hotfuzz--filtering-p)
+
 (defconst hotfuzz--bonus-lut
   (eval-when-compile
     (let ((state-special (make-char-table 'hotfuzz-bonus-lut 0))
@@ -154,6 +156,7 @@ will lead to inaccuracies."
      (t (cl-loop for x in-ref all do (setf x (cons (hotfuzz--cost needle x) x))
                  finally (setq all (mapcar #'cdr (sort all #'car-less-than-car))))))
     (when all
+      (setq hotfuzz--filtering-p (not (string= needle "")))
       (unless (string= needle "")
         (defvar completion-lazy-hilit-fn) ; Introduced in Emacs 30 (bug#47711)
         (if (bound-and-true-p completion-lazy-hilit)
@@ -174,10 +177,12 @@ will lead to inaccuracies."
                           (get-text-property 0 'completion-sorted (car completions)))
                       completions
                     (funcall existing-sort-fn completions)))))
-      `(metadata
-        (display-sort-function . ,(compose-sort-fn (or existing-dsf #'identity)))
-        (cycle-sort-function . ,(compose-sort-fn (or existing-csf #'identity)))
-        . ,(cdr metadata)))))
+      (if hotfuzz--filtering-p
+          `(metadata
+            (display-sort-function . ,(compose-sort-fn (or existing-dsf #'identity)))
+            (cycle-sort-function . ,(compose-sort-fn (or existing-csf #'identity)))
+            . ,(cdr metadata))
+        metadata))))
 
 ;;;###autoload
 (progn

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 92.64%. Comparing base (1afac1f) to head (9f9a38c).
Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master      #20      +/-   ##
==========================================
- Coverage   93.50%   92.64%   -0.86%     
==========================================
  Files           1        1              
  Lines          77       68       -9     
==========================================
- Hits           72       63       -9     
  Misses          5        5              

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[JohnWick95]

This feature appears to be partially implemented, as the history is currently ignored once typing begins.