[nongnu] elpa/with-editor 53a6b8a: with-editor-sleeping-editor-filter: Limit length of saved output

[ELPA Syncer]

branch: elpa/with-editor
commit 53a6b8ad8a6aabea3749366fb11f12a7dabcb11f
Author: Yikai Zhao <yikai@z1k.dev>
Commit: Jonas Bernoulli <jonas@bernoul.li>

    with-editor-sleeping-editor-filter: Limit length of saved output
    
    Improve performance by limitting the maximum length of the string
    saved in process filters.
    
    While using with `vterm', this `incomplete' string may get very
    large and it hurts performance.  In my case, it can easily get to few
    megabytes after using the same terminal for a long time, which would
    then increase the latency of each keystroke significantly.  We should
    only need to keep the last few bytes to make it work.
---
 lisp/with-editor.el | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/lisp/with-editor.el b/lisp/with-editor.el
index c0bf1dd..fcb3854 100644
--- a/lisp/with-editor.el
+++ b/lisp/with-editor.el
@@ -644,12 +644,19 @@ may not insert the text into the PROCESS's buffer.  Then 
it calls
 (defconst with-editor-sleeping-editor-regexp
   "^WITH-EDITOR: \\([0-9]+\\) OPEN \\([^]+?\\)\\(?: IN 
\\([^\r]+?\\)\\)?\r?$")
 
+(defvar with-editor--max-incomplete-length 1000)
+
 (defun with-editor-sleeping-editor-filter (process string)
   (when-let ((incomplete (and process (process-get process 'incomplete))))
     (setq string (concat incomplete string)))
   (save-match-data
     (cond
      ((and process (not (string-match-p "\n\\'" string)))
+      (let ((length (length string)))
+        (when (> length with-editor--max-incomplete-length)
+          (setq string
+                (substring string
+                           (- length with-editor--max-incomplete-length)))))
       (process-put process 'incomplete string)
       nil)
      ((string-match with-editor-sleeping-editor-regexp string)