[Emacs-diffs] emacs-25 91e6676: Fix an Isearch var to be a string (Bug#23038)

[Michael Heerdegen]

branch: emacs-25
commit 91e667692ba1362ca1334b8d58fd16c305ad5e2a
Author: Kaushal Modi <address@hidden>
Commit: Michael Heerdegen <address@hidden>

    Fix an Isearch var to be a string (Bug#23038)
    
    * isearch.el (isearch--describe-regexp-mode): The `description' var
      needs to always be a string.  Add the missing default case for the
      cond form that ensures that.
    
    Before this bug fix, for the events when `regexp-function' and
    `search-default-mode' both were nil, `description' also stayed nil.  So
    when `space-before' was non-nil, the "non-string" `description'
    (with a value of nil) got passed as an argument to
    `replace-regexp-in-string' (where a string was expected).  That caused
    the error described in Bug#23038.
---
 lisp/isearch.el |   19 +++++++++++--------
 1 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/lisp/isearch.el b/lisp/isearch.el
index 988503e..48354d3 100644
--- a/lisp/isearch.el
+++ b/lisp/isearch.el
@@ -2585,16 +2585,19 @@ the word mode."
                     (eq search-default-mode isearch-regexp))) "")
           ;; 2. Use the `isearch-message-prefix' set for
           ;;    `regexp-function' if available.
-               (regexp-function
-                (and (symbolp regexp-function)
-                     (or (get regexp-function 'isearch-message-prefix)
-                         "")))
+          (regexp-function
+           (and (symbolp regexp-function)
+                (or (get regexp-function 'isearch-message-prefix)
+                    "")))
           ;; 3. Else if `isearch-regexp' is non-nil, set description
           ;;    to "regexp ".
-               (isearch-regexp "regexp ")
-          ;; 4. And finally, if we're in literal mode (and if the
-          ;;    default mode is also not literal), describe it.
-               ((functionp search-default-mode) "literal "))))
+          (isearch-regexp "regexp ")
+          ;; 4. Else if we're in literal mode (and if the default
+          ;;    mode is also not literal), describe it.
+          ((functionp search-default-mode) "literal ")
+          ;; 5. And finally, if none of the above is true, set the
+          ;;    description to an empty string.
+          (t ""))))
     (if space-before
         ;; Move space from the end to the beginning.
         (replace-regexp-in-string "\\(.*\\) \\'" " \\1" description)