[elpa] master 9f21e1d 06/18: Add a matching optimization

[Oleh Krehel]

branch: master
commit 9f21e1d5258382f6426b5a08cea5971a8e955ad4
Author: Oleh Krehel <address@hidden>
Commit: Oleh Krehel <address@hidden>

    Add a matching optimization
    
    * ivy.el (ivy-completions): When the new regex `re' is a contains the
      old regex `ivy--old-re', it must be true that all candidates that
      match `re' are contained inside all candidates that match
      `ivy--old-re', i.e. the pre-computed in the last step
      `ivy--old-cands'.
    
    This should speed up completion for large (~100k) amount of candidates,
    for the particular case of regex simply being extended.
---
 ivy.el |   20 +++++++++++++-------
 1 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/ivy.el b/ivy.el
index bd43883..ebbb186 100644
--- a/ivy.el
+++ b/ivy.el
@@ -550,13 +550,19 @@ NAME is a string of words separated by spaces that is 
used to
 build a regex.
 CANDIDATES is a list of strings."
   (let* ((re (ivy--regex name))
-         (cands (if (and (equal re ivy--old-re)
-                         ivy--old-cands)
-                    ivy--old-cands
-                  (ignore-errors
-                    (cl-remove-if-not
-                     (lambda (x) (string-match re x))
-                     candidates))))
+         (cands (cond ((and (equal re ivy--old-re)
+                            ivy--old-cands)
+                       ivy--old-cands)
+                      ((and ivy--old-re (eq 0 (cl-search ivy--old-re re)))
+                       (ignore-errors
+                         (cl-remove-if-not
+                          (lambda (x) (string-match re x))
+                          ivy--old-cands)))
+                      (t
+                       (ignore-errors
+                         (cl-remove-if-not
+                          (lambda (x) (string-match re x))
+                          candidates)))))
          (tail (nthcdr ivy--index ivy--old-cands))
          (ww (window-width))
          idx)