* lisp/replace.el (occur-regexp-descr): New function.

(occur-1, occur-engine): Use it.

* lisp/isearch.el (isearch-occur): Propertize regexp with
isearch-string and isearch-regexp-function-descr for
occur-regexp-descr to display the correct description
message in the header (bug#21176, bug#21180).

2 files changed, 26 insertions, 8 deletions

diff --git a/lisp/isearch.el b/lisp/isearch.el
index 9f8ba8d8d7b..080eb578aa7 100644
--- a/lisp/isearch.el
+++ b/lisp/isearch.el
@@ -1828,7 +1828,13 @@ characters in that string."
                  isearch-regexp-lax-whitespace
                isearch-lax-whitespace)
              search-whitespace-regexp)))
-    (occur regexp nlines)))
+    (occur (if isearch-regexp-function
+               (propertize regexp
+                           'isearch-string isearch-string
+                           'isearch-regexp-function-descr
+                           (isearch--describe-regexp-mode isearch-regexp-function))
+             regexp)
+           nlines)))
 
 (declare-function hi-lock-read-face-name "hi-lock" ())
 
diff --git a/lisp/replace.el b/lisp/replace.el
index b6802aeaf57..7727562cf31 100644
--- a/lisp/replace.el
+++ b/lisp/replace.el
@@ -1416,6 +1416,17 @@ See also `multi-occur'."
                                buf))
                            (buffer-list))))))
 
+(defun occur-regexp-descr (regexp)
+  (format " for %s\"%s\""
+          (or (get-text-property 0 'isearch-regexp-function-descr regexp)
+              "")
+          (if (get-text-property 0 'isearch-string regexp)
+              (propertize
+               (query-replace-descr
+                (get-text-property 0 'isearch-string regexp))
+               'help-echo regexp)
+            (query-replace-descr regexp))))
+
 (defun occur-1 (regexp nlines bufs &optional buf-name)
   (unless (and regexp (not (equal regexp "")))
     (error "Occur doesn't work with the empty regexp"))
@@ -1484,9 +1495,11 @@ See also `multi-occur'."
                      (if (= count 1) "" "es")
                      ;; Don't display regexp if with remaining text
                      ;; it is longer than window-width.
-                     (if (> (+ (length regexp) 42) (window-width))
-                         "" (format-message
-                             " for `%s'" (query-replace-descr regexp)))))
+                     (if (> (+ (length (or (get-text-property 0 'isearch-string regexp)
+                                           regexp))
+                               42)
+                            (window-width))
+                         "" (occur-regexp-descr regexp))))
           (setq occur-revert-arguments (list regexp nlines bufs))
           (if (= count 0)
               (kill-buffer occur-buf)
@@ -1647,8 +1660,7 @@ See also `multi-occur'."
                                                   lines (if (= lines 1) "" "s")))
                                    ;; Don't display regexp for multi-buffer.
                                    (if (> (length buffers) 1)
-                                       "" (format " for \"%s\""
-                                                  (query-replace-descr regexp)))
+                                       "" (occur-regexp-descr regexp))
                                    (buffer-name buf))
                            'read-only t))
                   (setq end (point))
@@ -1661,14 +1673,14 @@ See also `multi-occur'."
         (goto-char (point-min))
         (let ((beg (point))
               end)
-          (insert (format "%d match%s%s total for \"%s\":\n"
+          (insert (format "%d match%s%s total%s:\n"
                           global-matches (if (= global-matches 1) "" "es")
                           ;; Don't display the same number of lines
                           ;; and matches in case of 1 match per line.
                           (if (= global-lines global-matches)
                               "" (format " in %d line%s"
                                          global-lines (if (= global-lines 1) "" "s")))
-                          (query-replace-descr regexp)))
+                          (occur-regexp-descr regexp)))
           (setq end (point))
           (when title-face
             (add-face-text-property beg end title-face)))