Only disable 'completion-preview-active-mode' when it is on

* lisp/completion-preview.el
(completion-preview--post-command): Avoid calling
'completion-preview-active-mode' to disable the mode when
already off, since it forces a costly redisplay. (Bug#76964)

diff --git a/lisp/completion-preview.el b/lisp/completion-preview.el
index 1c524985f055f4cbb82ff623ab6ba6f6e9204128..ae1394d27b40fc4e69ce5df34e090cb46a3e68d8 100644 (file)
--- a/lisp/completion-preview.el
+++ b/lisp/completion-preview.el
@@ -437,13 +437,17 @@ point, otherwise hide it."
       (cancel-timer completion-preview--timer)
       (setq completion-preview--timer nil))
 
-    ;; If we're called after a command that itself updates the
-    ;; preview, don't do anything.
-    (unless internal-p
-      (if (and (completion-preview-require-certain-commands)
-               (completion-preview-require-minimum-symbol-length))
-          (completion-preview--show)
-        (completion-preview-active-mode -1)))))
+    (cond
+     (internal-p
+      ;; `this-command' took care of updating the preview.  Do nothing.
+      )
+     ((and (completion-preview-require-certain-commands)
+           (completion-preview-require-minimum-symbol-length))
+      ;; All conditions met.  Show or update the preview.
+      (completion-preview--show))
+     (completion-preview-active-mode
+      ;; The preview is shown, but it shouldn't be.  Hide it.
+      (completion-preview-active-mode -1)))))
 
 (defun completion-preview-insert ()
   "Insert the completion candidate that the preview is showing."