Re: Isearch interaction model

[Juri Linkov]

>> because text properties on strings can't be saved
>> in the desktop file or by other history saving libraries.
>
> Couldn't we change that instead?

It seems text properties is the least bad of all other alternatives
that are not backward compatible and don't allow adding support for
search parameters to query-replace such as requested in bug#22479,
so with text properties this seems to be a better way, and adding
support to desktop for text properties is not unachievable:

diff --git a/lisp/desktop.el b/lisp/desktop.el
index 8bd4465..a7e549f 100644
--- a/lisp/desktop.el
+++ b/lisp/desktop.el
@@ -852,10 +852,7 @@ desktop--v2s
     ((or (numberp value) (null value) (eq t value) (keywordp value))
      (cons 'may value))
     ((stringp value)
-     (let ((copy (copy-sequence value)))
-       (set-text-properties 0 (length copy) nil copy)
-       ;; Get rid of text properties because we cannot read them.
-       (cons 'may copy)))
+     (cons 'may value))
     ((symbolp value)
      (cons 'must value))
     ((vectorp value)
diff --git a/lisp/isearch.el b/lisp/isearch.el
index 4f5f494..0699868 100644
--- a/lisp/isearch.el
+++ b/lisp/isearch.el
@@ -1119,7 +1119,9 @@ isearch-done
 
   (if (and (> (length isearch-string) 0) (not nopush))
       ;; Update the ring data.
-      (isearch-update-ring isearch-string isearch-regexp))
+      (isearch-update-ring isearch-string isearch-regexp
+                           `(regexp-function ,isearch-regexp-function
+                             case-fold-search ,isearch-case-fold-search)))
 
   (let ((isearch-mode-end-hook-quit (and nopush (not edit))))
     (run-hooks 'isearch-mode-end-hook))
@@ -1135,12 +1137,12 @@ isearch-done
 
   (and (not edit) isearch-recursive-edit (exit-recursive-edit)))
 
-(defun isearch-update-ring (string &optional regexp)
+(defun isearch-update-ring (string &optional regexp properties)
   "Add STRING to the beginning of the search ring.
 REGEXP if non-nil says use the regexp search ring."
   (add-to-history
    (if regexp 'regexp-search-ring 'search-ring)
-   string
+   (if properties (apply 'propertize string properties) string)
    (if regexp regexp-search-ring-max search-ring-max)))
 
 ;; Switching buffers should first terminate isearch-mode.
@@ -1850,7 +1852,11 @@ isearch-query-replace
        ;; `exit-recursive-edit' in `isearch-done' that terminates
        ;; the execution of this command when it is non-nil.
        ;; We call `exit-recursive-edit' explicitly at the end below.
-       (isearch-recursive-edit nil))
+       (isearch-recursive-edit nil)
+        (isearch-string-propertized
+         (propertize isearch-string
+                    'isearch-regexp-function isearch-regexp-function
+                    'isearch-case-fold-search isearch-case-fold-search)))
     (isearch-done nil t)
     (isearch-clean-overlays)
     (if (and isearch-other-end
@@ -1863,12 +1869,12 @@ isearch-query-replace
                         (< (mark) (point))))))
         (goto-char isearch-other-end))
     (set query-replace-from-history-variable
-         (cons isearch-string
+         (cons isearch-string-propertized
                (symbol-value query-replace-from-history-variable)))
     (perform-replace
-     isearch-string
+     isearch-string-propertized
      (query-replace-read-to
-      isearch-string
+      isearch-string-propertized
       (concat "Query replace"
               (isearch--describe-regexp-mode (or delimited 
isearch-regexp-function) t)
              (if backward " backward" "")
@@ -2572,7 +2578,13 @@ isearch-ring-adjust1
                      length)))
       (setq isearch-string (nth yank-pointer ring)
            isearch-message (mapconcat 'isearch-text-char-description
-                                      isearch-string "")))))
+                                      isearch-string ""))
+      (when (memq 'regexp-function (text-properties-at 0 isearch-string))
+        (setq isearch-regexp-function
+              (get-text-property 0 'regexp-function isearch-string)))
+      (when (memq 'case-fold-search (text-properties-at 0 isearch-string))
+        (setq isearch-case-fold-search
+              (get-text-property 0 'case-fold-search isearch-string))))))
 
 (defun isearch-ring-adjust (advance)
   ;; Helper for isearch-ring-advance and isearch-ring-retreat
@@ -2788,11 +2800,15 @@ isearch-search-fun
 
 (defun isearch--lax-regexp-function-p ()
   "Non-nil if next regexp-function call should be lax."
+  ;; FIXME: maybe simpler to use this:
+  ;; (or (memq this-command '(isearch-printing-char isearch-del-char)) 
isearch-yank-flag)
   (not (or isearch-nonincremental
            (null (car isearch-cmds))
            (eq (length isearch-string)
                (length (isearch--state-string
-                        (car isearch-cmds)))))))
+                        (car isearch-cmds))))
+           ;; Search string comes from the history with text properties
+           (memq 'regexp-function (text-properties-at 0 isearch-string)))))
 
 (defun isearch-search-fun-default ()
   "Return default functions to use for the search."
diff --git a/lisp/replace.el b/lisp/replace.el
index c28c9b3..ac37bd7 100644
--- a/lisp/replace.el
+++ b/lisp/replace.el
@@ -301,7 +301,9 @@ query-replace-read-args
         (to (if (consp from) (prog1 (cdr from) (setq from (car from)))
               (query-replace-read-to from prompt regexp-flag))))
     (list from to
-         (and current-prefix-arg (not (eq current-prefix-arg '-)))
+         (or (and current-prefix-arg (not (eq current-prefix-arg '-)))
+              (and (memq 'isearch-regexp-function (text-properties-at 0 from))
+                   (get-text-property 0 'isearch-regexp-function from)))
          (and current-prefix-arg (eq current-prefix-arg '-)))))
 
 (defun query-replace (from-string to-string &optional delimited start end 
backward region-noncontiguous-p)
@@ -2361,8 +2363,17 @@ perform-replace
          (message
           (if query-flag
               (apply 'propertize
-                     (substitute-command-keys
-                      "Query replacing %s with %s: 
(\\<query-replace-map>\\[help] for help) ")
+                     (concat "Query replacing "
+                             (if backward "backward " "")
+                             (if delimited-flag
+                                 (or (and (symbolp delimited-flag)
+                                          (get delimited-flag
+                                               'isearch-message-prefix))
+                                     "word ") "")
+                             (if regexp-flag "regexp " "")
+                             "%s with %s: "
+                             (substitute-command-keys
+                              "(\\<query-replace-map>\\[help] for help) "))
                      minibuffer-prompt-properties))))
 
     ;; Unless a single contiguous chunk is selected, operate on multiple 
chunks.
@@ -2580,13 +2591,13 @@ perform-replace
                         (with-output-to-temp-buffer "*Help*"
                           (princ
                            (concat "Query replacing "
+                                   (if backward "backward " "")
                                    (if delimited-flag
                                        (or (and (symbolp delimited-flag)
                                                 (get delimited-flag
                                                       'isearch-message-prefix))
                                            "word ") "")
                                    (if regexp-flag "regexp " "")
-                                   (if backward "backward " "")
                                    from-string " with "
                                    next-replacement ".\n\n"
                                    (substitute-command-keys