company--capf-data: use caching

[gnu-emacs-elpa] / company-capf.el

diff --git a/company-capf.el b/company-capf.el
index 77479aeeec70937fcde83e44abb38519dc8364c5..b630025690f498063f554fb75463d2c07fa0f678 100644 (file)
--- a/company-capf.el
+++ b/company-capf.el
@@ -25,20 +25,36 @@
 
 ;;; Code:
 
-(eval-when-compile (require 'cl))
+(require 'company)
+(require 'cl-lib)
+
+(defvar company--capf-cache nil)
 
 (defun company--capf-data ()
-  ;; Ignore tags-completion-at-point-function because it subverts company-etags
-  ;; in the default value of company-backends, where the latter comes later.
-  (letf* (((default-value 'completion-at-point-functions) nil)
-          (data (run-hook-wrapped 'completion-at-point-functions
-                                  ;; Ignore misbehaving functions.
-                                  #'completion--capf-wrapper 'optimist)))
-    (when (and (consp data) (numberp (nth 1 data))) data)))
+  (let ((cache company--capf-cache))
+    (if (and (equal (current-buffer) (car cache))
+             (equal (point) (car (setq cache (cdr cache))))
+             (equal (buffer-chars-modified-tick) (car (setq cache (cdr cache)))))
+        (cadr cache)
+      (let ((data (company--capf-data-real)))
+        (setq company--capf-cache
+              (list (current-buffer) (point) (buffer-chars-modified-tick) data))
+        data))))
+
+(defun company--capf-data-real ()
+  (cl-letf* (((default-value 'completion-at-point-functions)
+              ;; Ignore tags-completion-at-point-function because it subverts
+              ;; company-etags in the default value of company-backends, where
+              ;; the latter comes later.
+              (remove 'tags-completion-at-point-function
+                      (default-value 'completion-at-point-functions)))
+             (data (run-hook-wrapped 'completion-at-point-functions
+                                     ;; Ignore misbehaving functions.
+                                     #'completion--capf-wrapper 'optimist)))
+    (when (and (consp (cdr data)) (numberp (nth 1 data))) data)))
 
 (defun company-capf (command &optional arg &rest _args)
-  "`company-mode' back-end using `completion-at-point-functions'.
-Requires Emacs 24.1 or newer."
+  "`company-mode' back-end using `completion-at-point-functions'."
   (interactive (list 'interactive))
   (pcase command
     (`interactive (company-begin-backend 'company-capf))
@@ -77,18 +93,18 @@ Requires Emacs 24.1 or newer."
                       (buffer-substring (nth 1 res) (nth 2 res))
                       (nth 3 res) (plist-get (nthcdr 4 res) :predicate))))
            (cdr (assq 'display-sort-function meta))))))
-    (`common-part
+    (`match
      ;; Can't just use 0 when base-size (see above) is non-zero.
-     (let ((start (if (get-text-property 0 'face arg)
+     (let ((start (if (get-text-property 0 'font-lock-face arg)
                       0
-                    (next-single-property-change 0 'face arg))))
+                    (next-single-property-change 0 'font-lock-face arg))))
        (when start
          ;; completions-common-part comes first, but we can't just look for this
          ;; value because it can be in a list.
          (or
-          (let ((value (get-text-property start 'face arg)))
+          (let ((value (get-text-property start 'font-lock-face arg)))
             (text-property-not-all start (length arg)
-                                   'face value arg))
+                                   'font-lock-face value arg))
           (length arg)))))
     (`duplicates t)
     (`no-cache t)   ;Not much can be done here, as long as we handle
@@ -106,7 +122,13 @@ Requires Emacs 24.1 or newer."
      (save-excursion
        ;; FIXME: `company-begin' sets `company-point' after calling
        ;; `company--begin-new'.  We shouldn't rely on `company-point' here,
-       ;; better to cache the capf-data value instead.
+       ;; better to cache the capf-data value instead.  However: we can't just
+       ;; save the last capf-data value in `prefix', because that command can
+       ;; get called more often than `candidates', and at any point in the
+       ;; buffer (https://github.com/company-mode/company-mode/issues/153).
+       ;; We could try propertizing the returned prefix string, but it's not
+       ;; passed to `annotation', and `company-prefix' is set only after
+       ;; `company--strip-duplicates' is called.
        (when company-point
          (goto-char company-point))
        (let ((f (plist-get (nthcdr 4 (company--capf-data)) :annotation-function)))