Speed up widget creation (Bug#53606)

* lisp/wid-edit.el (widget-default-create, widget-checklist-add-item)
(widget-radio-add-item, widget-editable-list-entry-create): Don't
insert format escapes into the buffer, only to delete them after.
This avoids calls to delete-char and makes widget creation about 3
times faster.

1 files changed, 47 insertions, 27 deletions

diff --git a/lisp/wid-edit.el b/lisp/wid-edit.el
index a1d4c4850ae..2d6075c10a8 100644
--- a/lisp/wid-edit.el
+++ b/lisp/wid-edit.el
@@ -1776,18 +1776,20 @@ to a given widget."
 (defun widget-default-create (widget)
   "Create WIDGET at point in the current buffer."
   (widget-specify-insert
-   (let ((from (point))
+   (let ((str (widget-get widget :format))
+         (onext 0) (next 0)
          button-begin button-end
          sample-begin sample-end
          doc-begin doc-end
          value-pos
          (markers (widget--prepare-markers-for-inside-insertion widget)))
-     (insert (widget-get widget :format))
-     (goto-char from)
      ;; Parse escapes in format.
-     (while (re-search-forward "%\\(.\\)" nil t)
-       (let ((escape (char-after (match-beginning 1))))
-         (delete-char -2)
+     (while (string-match "%\\(.\\)" str next)
+       (setq next (match-end 1))
+       ;; If we skipped some literal text, insert it.
+       (when (/= (- next onext) 2)
+         (insert (substring str onext (- next 2))))
+       (let ((escape (string-to-char (match-string 1 str))))
          (cond ((eq escape ?%)
                 (insert ?%))
                ((eq escape ?\[)
@@ -1831,7 +1833,11 @@ to a given widget."
                     (widget-apply widget :value-create)
                   (setq value-pos (point))))
                (t
-                (widget-apply widget :format-handler escape)))))
+                (widget-apply widget :format-handler escape))))
+       (setq onext next))
+     ;; Insert remaining literal text, if any.
+     (when (> (length str) next)
+       (insert (substring str next)))
      ;; Specify button, sample, and doc, and insert value.
      (and button-begin button-end
           (widget-specify-button widget button-begin button-end))
@@ -2578,14 +2584,15 @@ If the item is checked, CHOSEN is a cons whose cdr is the value."
           (buttons (widget-get widget :buttons))
           (button-args (or (widget-get type :sibling-args)
                            (widget-get widget :button-args)))
-          (from (point))
+          (str (widget-get widget :entry-format))
+          (onext 0) (next 0)
           child button)
-     (insert (widget-get widget :entry-format))
-     (goto-char from)
      ;; Parse % escapes in format.
-     (while (re-search-forward "%\\([bv%]\\)" nil t)
-       (let ((escape (char-after (match-beginning 1))))
-         (delete-char -2)
+     (while (string-match "%\\([bv%]\\)" str next)
+       (setq next (match-end 1))
+       (when (/= (- next onext) 2)
+         (insert (substring str onext (- next 2))))
+       (let ((escape (string-to-char (match-string 1 str))))
          (cond ((eq escape ?%)
                 (insert ?%))
                ((eq escape ?b)
@@ -2609,7 +2616,10 @@ If the item is checked, CHOSEN is a cons whose cdr is the value."
                              (widget-create-child-value
                               widget type (car (cdr chosen)))))))
                (t
-                (error "Unknown escape `%c'" escape)))))
+                (error "Unknown escape `%c'" escape))))
+       (setq onext next))
+     (when (> (length str) next)
+       (insert (substring str next)))
      ;; Update properties.
      (and button child (widget-put child :button button))
      (and button (widget-put widget :buttons (cons button buttons)))
@@ -2756,16 +2766,17 @@ Return an alist of (TYPE MATCH)."
           (buttons (widget-get widget :buttons))
           (button-args (or (widget-get type :sibling-args)
                            (widget-get widget :button-args)))
-          (from (point))
+          (str (widget-get widget :entry-format))
+          (onext 0) (next 0)
           (chosen (and (null (widget-get widget :choice))
                        (widget-apply type :match value)))
           child button)
-     (insert (widget-get widget :entry-format))
-     (goto-char from)
      ;; Parse % escapes in format.
-     (while (re-search-forward "%\\([bv%]\\)" nil t)
-       (let ((escape (char-after (match-beginning 1))))
-         (delete-char -2)
+     (while (string-match "%\\([bv%]\\)" str next)
+       (setq next (match-end 1))
+       (when (/= (- next onext) 2)
+         (insert (substring str onext (- next 2))))
+       (let ((escape (string-to-char (match-string 1 str))))
          (cond ((eq escape ?%)
                 (insert ?%))
                ((eq escape ?b)
@@ -2784,7 +2795,10 @@ Return an alist of (TYPE MATCH)."
                         (to (widget-get child :to)))
                     (widget-specify-unselected child from to))))
                (t
-                (error "Unknown escape `%c'" escape)))))
+                (error "Unknown escape `%c'" escape))))
+       (setq onext next))
+     (when (> (length str) next)
+       (insert (substring str next)))
      ;; Update properties.
      (when chosen
        (widget-put widget :choice type))
@@ -3053,17 +3067,20 @@ Save CHILD into the :last-deleted list, so it can be inserted later."
   ;; Create a new entry to the list.
   (let ((type (nth 0 (widget-get widget :args)))
         ;; (widget-push-button-gui widget-editable-list-gui)
+        (str (widget-get widget :entry-format))
+        (onext 0) (next 0)
         child delete insert)
     (widget-specify-insert
      (save-excursion
        (and (widget--should-indent-p)
             (widget-get widget :indent)
-            (insert-char ?\s (widget-get widget :indent)))
-       (insert (widget-get widget :entry-format)))
+            (insert-char ?\s (widget-get widget :indent))))
      ;; Parse % escapes in format.
-     (while (re-search-forward "%\\(.\\)" nil t)
-       (let ((escape (char-after (match-beginning 1))))
-         (delete-char -2)
+     (while (string-match "%\\(.\\)" str next)
+       (setq next (match-end 1))
+       (when (/= (- next onext) 2)
+         (insert (substring str onext (- next 2))))
+       (let ((escape (string-to-char (match-string 1 str))))
          (cond ((eq escape ?%)
                 (insert ?%))
                ((eq escape ?i)
@@ -3079,7 +3096,10 @@ Save CHILD into the :last-deleted list, so it can be inserted later."
                              widget type
                              (if conv value (widget-default-get type)))))
                (t
-                (error "Unknown escape `%c'" escape)))))
+                (error "Unknown escape `%c'" escape))))
+       (setq onext next))
+     (when (> (length str) next)
+       (insert (substring str next)))
      (let ((buttons (widget-get widget :buttons)))
        (if insert (push insert buttons))
        (if delete (push delete buttons))