Re: grep error because of bad previous input

[Richard Stallman <rms@gnu.org>]

Does this fix it?

*** grep.el	19 Jul 2006 17:19:19 -0400	1.62
--- grep.el	27 Jul 2006 19:15:01 -0400	
***************
*** 456,488 ****
  		 t)))))
  
  (defun grep-default-command ()
    (let ((tag-default
           (shell-quote-argument
            (or (funcall (or find-tag-default-function
                             (get major-mode 'find-tag-default-function)
                             'find-tag-default))
                "")))
  	(sh-arg-re "\\(\\(?:\"\\(?:[^\"]\\|\\\\\"\\)+\"\\|'[^']+'\\|[^\"' \t\n]\\)+\\)")
  	(grep-default (or (car grep-history) grep-command)))
!     ;; Replace the thing matching for with that around cursor.
      (when (or (string-match
  	       (concat "[^ ]+\\s +\\(?:-[^ ]+\\s +\\)*"
  		       sh-arg-re "\\(\\s +\\(\\S +\\)\\)?")
  	       grep-default)
  	      ;; If the string is not yet complete.
  	      (string-match "\\(\\)\\'" grep-default))
!       (unless (or (not (stringp buffer-file-name))
! 		  (when (match-beginning 2)
! 		    (save-match-data
! 		      (string-match
! 		       (wildcard-to-regexp
! 			(file-name-nondirectory
! 			 (match-string 3 grep-default)))
! 		       (file-name-nondirectory buffer-file-name)))))
! 	(setq grep-default (concat (substring grep-default
! 					      0 (match-beginning 2))
! 				   " *."
! 				   (file-name-extension buffer-file-name))))
        (replace-match tag-default t t grep-default 1))))
  
  
--- 456,499 ----
  		 t)))))
  
  (defun grep-default-command ()
+   "Compute the default grep command for C-u M-x grep to offer."
    (let ((tag-default
+ 	 ;; Find the tag in the buffer at point.
           (shell-quote-argument
            (or (funcall (or find-tag-default-function
                             (get major-mode 'find-tag-default-function)
                             'find-tag-default))
                "")))
+ 	;; Is this a regexp to match single shell arguments?
+ 	;; I guess so.  Does someone know?
  	(sh-arg-re "\\(\\(?:\"\\(?:[^\"]\\|\\\\\"\\)+\"\\|'[^']+'\\|[^\"' \t\n]\\)+\\)")
  	(grep-default (or (car grep-history) grep-command)))
!     ;; In the default command, find the arg that specifies the pattern.
      (when (or (string-match
  	       (concat "[^ ]+\\s +\\(?:-[^ ]+\\s +\\)*"
  		       sh-arg-re "\\(\\s +\\(\\S +\\)\\)?")
  	       grep-default)
  	      ;; If the string is not yet complete.
  	      (string-match "\\(\\)\\'" grep-default))
!       ;; Maybe we will replace the pattern with the default tag.
!       ;; But first, maybe replace the file name pattern.
!       (condition-case nil
! 	  (unless (or (not (stringp buffer-file-name))
! 		      (when (match-beginning 2)
! 			(save-match-data
! 			  (string-match
! 			   (wildcard-to-regexp
! 			    (file-name-nondirectory
! 			     (match-string 3 grep-default)))
! 			   (file-name-nondirectory buffer-file-name)))))
! 	    (setq grep-default (concat (substring grep-default
! 						  0 (match-beginning 2))
! 				       " *."
! 				       (file-name-extension buffer-file-name))))
! 	;; In case wildcard-to-regexp gets an error
! 	;; from invalid data.
! 	(error nil))
!       ;; Now replace the pattern with the default tag.
        (replace-match tag-default t t grep-default 1))))