[elpa] master 68f5f4e 226/281: ivy.el: Add a small refresh delay for dynamic collections.

[Oleh Krehel]

branch: master
commit 68f5f4ea73929f7546a7e767ef89dc76c9c34e96
Author: Jérôme M. Berger <jeber...@free.fr>
Commit: Oleh Krehel <ohwoeo...@gmail.com>

    ivy.el: Add a small refresh delay for dynamic collections.
    
    This is probably a good idea performance-wise since it limits the number
    of collection updates when the user is typing. However, the main reason
    for this change is to work around an Emacs freeze on Windows when the
    dynamic collection is generated by an external command (see for example
    this bug in helm-ag which also affects counsel-ag and similar commands:
    https://github.com/syohex/emacs-helm-ag/issues/188).
    
    Related to #1218 (but only applies for dynamic collections, where the
    difference is really noticeable).
    Helps with #1198 and #786.
    
    Fixes #1237
---
 ivy.el | 27 ++++++++++++++++++++++++---
 1 file changed, 24 insertions(+), 3 deletions(-)

diff --git a/ivy.el b/ivy.el
index 9b65020..1335912 100644
--- a/ivy.el
+++ b/ivy.el
@@ -1655,7 +1655,7 @@ customizations apply to the current completion session."
                                        (delete item
                                                (cdr (symbol-value hist))))))))
                  (ivy-state-current ivy-last)))
-          (remove-hook 'post-command-hook #'ivy--exhibit)
+          (remove-hook 'post-command-hook #'ivy--queue-exhibit)
           (when (eq ivy-display-function 'ivy-display-function-overlay)
             (ivy-overlay-cleanup))
           (when (setq unwind (ivy-state-unwind ivy-last))
@@ -2354,7 +2354,7 @@ tries to ensure that it does not change depending on the 
number of candidates."
                                (if ivy-add-newline-after-prompt
                                    1
                                  0))))
-  (add-hook 'post-command-hook #'ivy--exhibit nil t)
+  (add-hook 'post-command-hook #'ivy--queue-exhibit nil t)
   ;; show completions with empty input
   (ivy--exhibit))
 
@@ -2570,10 +2570,31 @@ Possible choices are 
'ivy-magic-slash-non-match-cd-selected,
 Otherwise, ~/ will move home."
   :type 'boolean)
 
+(defcustom ivy-dynamic-exhibit-delay-ms 0
+  "Delay in ms before dynamic collections are refreshed"
+  :type 'integer)
+
+(defvar ivy--exhibit-timer nil)
+
+(defun ivy--queue-exhibit ()
+  "Insert Ivy completions display, possibly after a timeout for
+dynamic collections.
+Should be run via minibuffer `post-command-hook'."
+  (if (and (> ivy-dynamic-exhibit-delay-ms 0)
+           (ivy-state-dynamic-collection ivy-last))
+      (progn
+        (when ivy--exhibit-timer (cancel-timer ivy--exhibit-timer))
+        (setq ivy--exhibit-timer
+              (run-with-timer
+               (/ ivy-dynamic-exhibit-delay-ms 1000.0)
+               nil
+               'ivy--exhibit)))
+    (ivy--exhibit)))
+
 (defun ivy--exhibit ()
   "Insert Ivy completions display.
 Should be run via minibuffer `post-command-hook'."
-  (when (memq 'ivy--exhibit post-command-hook)
+  (when (memq 'ivy--queue-exhibit post-command-hook)
     (let ((inhibit-field-text-motion nil))
       (constrain-to-field nil (point-max)))
     (setq ivy-text (ivy--input))