Rewrite the minibuffer lazy highlight feature

The new API was discussed in bug#53126.  It's more robust and easier
to use in complex cases like that of 'query-replace'.

* etc/NEWS: Amend the feature announcement
* lisp/isearch.el (isearch-edit-string): Use new API.
(minibuffer-lazy-highlight-transform,
minibuffer-lazy-highlight--overlay, minibuffer-lazy-highlight--count,
minibuffer-lazy-highlight--after-change,
minibuffer-lazy-highlight--exit) Remove helper functions, which are
now kept together with the lazy highlight configuration variables
within a closure.
(minibuffer-lazy-highlight-setup): This function now takes the lazy
highlighting configuration variables as argument, and returns a
closure that is intended to run as part of the minibuffer setup.

2 files changed, 88 insertions, 65 deletions

diff --git a/etc/NEWS b/etc/NEWS
index 2fac893cc52..2cddfcc8db6 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -1593,9 +1593,8 @@ the clipboard, and insert it into the buffer.
 
 ---
 ** New function 'minibuffer-lazy-highlight-setup'.
-This function is intended to be added to 'minibuffer-setup-hook'.
-It sets up the minibuffer for lazy highlighting of matches
-in the original window.
+This function allows to set up the minibuffer so that lazy
+highlighting of its content is applied in the original window.
 
 +++
 ** New text property 'inhibit-isearch'.
diff --git a/lisp/isearch.el b/lisp/isearch.el
index 956b115ce42..168d71ada3a 100644
--- a/lisp/isearch.el
+++ b/lisp/isearch.el
@@ -1812,20 +1812,20 @@ The following additional command keys are active while editing.
 	  (minibuffer-history-symbol)
 	  ;; Search string might have meta information on text properties.
 	  (minibuffer-allow-text-properties t))
-     (when isearch-lazy-highlight
-       (add-hook 'minibuffer-setup-hook #'minibuffer-lazy-highlight-setup))
      (setq isearch-new-string
-	   (read-from-minibuffer
-	    (isearch-message-prefix nil isearch-nonincremental)
-	    (cons isearch-string (1+ (or (isearch-fail-pos)
-					 (length isearch-string))))
-	    minibuffer-local-isearch-map nil
-	    (if isearch-regexp
-		(cons 'regexp-search-ring
-		      (1+ (or regexp-search-ring-yank-pointer -1)))
-	      (cons 'search-ring
-		    (1+ (or search-ring-yank-pointer -1))))
-	    nil t)
+	   (minibuffer-with-setup-hook
+               (minibuffer-lazy-highlight-setup)
+             (read-from-minibuffer
+	      (isearch-message-prefix nil isearch-nonincremental)
+	      (cons isearch-string (1+ (or (isearch-fail-pos)
+					   (length isearch-string))))
+	      minibuffer-local-isearch-map nil
+	      (if isearch-regexp
+		  (cons 'regexp-search-ring
+		        (1+ (or regexp-search-ring-yank-pointer -1)))
+	        (cons 'search-ring
+		      (1+ (or search-ring-yank-pointer -1))))
+	      nil t))
 	   isearch-new-message
 	   (mapconcat 'isearch-text-char-description
 		      isearch-new-string "")))))
@@ -4361,57 +4361,81 @@ Attempt to do the search exactly the way the pending Isearch would."
   :group 'lazy-count
   :version "29.1")
 
-(defvar minibuffer-lazy-highlight-transform #'identity
-  "Function to transform minibuffer text into a `isearch-string' for highlighting.")
-
-(defvar minibuffer-lazy-highlight--overlay nil
-  "Overlay for minibuffer prompt updates.")
-
-(defun minibuffer-lazy-highlight--count ()
-  "Display total match count in the minibuffer prompt."
-  (when minibuffer-lazy-highlight--overlay
-    (overlay-put minibuffer-lazy-highlight--overlay
-                 'before-string
-                 (and isearch-lazy-count-total
-                      (not isearch-error)
-                      (format minibuffer-lazy-count-format
-                              isearch-lazy-count-total)))))
-
-(defun minibuffer-lazy-highlight--after-change (_beg _end _len)
-  "Update lazy highlight state in minibuffer selected window."
-  (when isearch-lazy-highlight
-    (let ((inhibit-redisplay t) ;; Avoid cursor flickering
-          (string (minibuffer-contents)))
-      (with-minibuffer-selected-window
-        (setq isearch-string (funcall minibuffer-lazy-highlight-transform string))
-        (isearch-lazy-highlight-new-loop)))))
-
-(defun minibuffer-lazy-highlight--exit ()
-  "Unwind changes from `minibuffer-lazy-highlight-setup'."
-  (remove-hook 'after-change-functions
-               #'minibuffer-lazy-highlight--after-change)
-  (remove-hook 'lazy-count-update-hook #'minibuffer-lazy-highlight--count)
-  (remove-hook 'minibuffer-exit-hook #'minibuffer-lazy-highlight--exit)
-  (setq minibuffer-lazy-highlight--overlay nil)
-  (when lazy-highlight-cleanup
-    (lazy-highlight-cleanup)))
-
-(defun minibuffer-lazy-highlight-setup ()
+(cl-defun minibuffer-lazy-highlight-setup
+    (&key (highlight isearch-lazy-highlight)
+          (cleanup lazy-highlight-cleanup)
+          (transform #'identity)
+          (filter nil)
+          (regexp isearch-regexp)
+          (regexp-function isearch-regexp-function)
+          (case-fold isearch-case-fold-search)
+          (lax-whitespace (if regexp
+                              isearch-regexp-lax-whitespace
+                            isearch-lax-whitespace)))
   "Set up minibuffer for lazy highlight of matches in the original window.
 
-This function is intended to be added to `minibuffer-setup-hook'.
-Note that several other isearch variables influence the lazy
-highlighting, including `isearch-regexp',
-`isearch-lazy-highlight' and `isearch-lazy-count'."
-  (remove-hook 'minibuffer-setup-hook #'minibuffer-lazy-highlight-setup)
-  (add-hook 'after-change-functions
-            #'minibuffer-lazy-highlight--after-change)
-  (add-hook 'lazy-count-update-hook #'minibuffer-lazy-highlight--count)
-  (add-hook 'minibuffer-exit-hook #'minibuffer-lazy-highlight--exit)
-  (setq minibuffer-lazy-highlight--overlay
-        (and minibuffer-lazy-count-format
-             (make-overlay (point-min) (point-min) (current-buffer) t)))
-  (minibuffer-lazy-highlight--after-change nil nil nil))
+This function return a closure intended to be added to
+`minibuffer-setup-hook'.  It accepts the following keyword
+arguments, all of which have a default based on the current
+isearch settings.
+
+HIGHLIGHT: Whether to perform lazy highlight.
+CLEANUP: Whether to clean up the lazy highlight when the minibuffer
+exits.
+TRANSFORM: A function taking one argument, the minibuffer contents,
+and returning the `isearch-string' to use for lazy highlighting.
+FILTER: A function to add to `isearch-filter-predicate'.
+REGEXP: The value of `isearch-regexp' to use for lazy highlighting.
+REGEXP-FUNCTION: The value of `isearch-regexp-function' to use for
+lazy highlighting.
+CASE-FOLD: The value of `isearch-case-fold' to use for lazy
+highlighting.
+LAX-WHITESPACE: The value of `isearch-lax-whitespace' and
+`isearch-regexp-lax-whitespace' to use for lazy highlighting."
+  (if (not highlight)
+      #'ignore
+    (let ((unwind (make-symbol "minibuffer-lazy-highlight--unwind"))
+          (after-change (make-symbol "minibuffer-lazy-highlight--after-change"))
+          (display-count (make-symbol "minibuffer-lazy-highlight--display-count"))
+          overlay)
+      (fset unwind
+            (lambda ()
+              (remove-function isearch-filter-predicate filter)
+              (remove-hook 'lazy-count-update-hook display-count)
+              (when overlay (delete-overlay overlay))
+              (remove-hook 'after-change-functions after-change)
+              (remove-hook 'minibuffer-exit-hook unwind)
+              (let ((lazy-highlight-cleanup cleanup))
+                (lazy-highlight-cleanup))))
+      (fset after-change
+            (lambda (_beg _end _len)
+              (let ((inhibit-redisplay t) ;; Avoid cursor flickering
+                    (string (minibuffer-contents)))
+                (with-minibuffer-selected-window
+                  (let* ((isearch-forward t)
+                         (isearch-regexp regexp)
+                         (isearch-regexp-function regexp-function)
+                         (isearch-case-fold-search case-fold)
+                         (isearch-lax-whitespace lax-whitespace)
+                         (isearch-regexp-lax-whitespace lax-whitespace)
+                         (isearch-string (funcall transform string)))
+                    (isearch-lazy-highlight-new-loop))))))
+      (fset display-count
+            (lambda ()
+              (overlay-put overlay 'before-string
+                           (and isearch-lazy-count-total
+                                (not isearch-error)
+                                (format minibuffer-lazy-count-format
+                                        isearch-lazy-count-total)))))
+      (lambda ()
+        (add-hook 'minibuffer-exit-hook unwind)
+        (add-hook 'after-change-functions after-change)
+        (when minibuffer-lazy-count-format
+          (setq overlay (make-overlay (point-min) (point-min) (current-buffer) t))
+          (add-hook 'lazy-count-update-hook display-count))
+        (when filter
+          (add-function :after-while isearch-filter-predicate filter))
+        (funcall after-change nil nil nil)))))
 
 
 (defun isearch-resume (string regexp word forward message case-fold)