bug#9438: grep regressions

[Juri Linkov <juri@jurta.org>]

grep used to navigate directly to the correct column and highlight the
match instantly with `next-error-highlight'.  But now grep.el doesn't do
that because escape sequences are processed earlier than font-locking.

One way to fix this regression is to find matches highligted by
`grep-filter' and take their column positions.

Unfortunately, I can't find a simpler way to fix it than this patch:

=== modified file 'lisp/progmodes/grep.el'
--- lisp/progmodes/grep.el	2011-08-22 09:54:38 +0000
+++ lisp/progmodes/grep.el	2011-09-05 08:30:35 +0000
@@ -344,7 +344,27 @@ (defvar grep-last-buffer nil
 ;;;###autoload
 (defconst grep-regexp-alist
   '(("^\\(.+?\\)\\(:[ \t]*\\)\\([1-9][0-9]*\\)\\2"
-     1 3)
+     1 3
+     ;; Calculate column positions (col . end-col) of first grep match on a line
+     ((lambda ()
+	(when grep-highlight-matches
+	  (setq compilation-error-screen-columns nil)
+	  (save-excursion
+	    (let* ((beg (progn (goto-char (match-end 0)) (point)))
+		   (end (line-end-position))
+		   (mbeg (text-property-any beg end 'font-lock-face 'match)))
+	      (when mbeg
+		(- mbeg beg))))))
+      .
+      (lambda ()
+	(when grep-highlight-matches
+	  (save-excursion
+	    (let* ((beg (progn (goto-char (match-end 0)) (point)))
+		   (end (line-end-position))
+		   (mbeg (text-property-any beg end 'font-lock-face 'match))
+		   (mend (and mbeg (next-single-property-change mbeg 'font-lock-face nil end))))
+	      (when mend
+		(- mend beg))))))))
     ;; Rule to match column numbers is commented out since no known grep
     ;; produces them
     ;; ("^\\(.+?\\)\\(:[ \t]*\\)\\([0-9]+\\)\\2\\(?:\\([0-9]+\\)\\(?:-\\([0-9]+\\)\\)?\\2\\)?"
@@ -353,17 +373,6 @@ (defconst grep-regexp-alist
     ;; handle weird file names (with colons in them) as well as possible.
     ;; E.g. we use [1-9][0-9]* rather than [0-9]+ so as to accept ":034:" in
     ;; file names.
-    ("^\\(\\(.+?\\):\\([1-9][0-9]*\\):\\).*?\
-\\(\033\\[01;31m\\(?:\033\\[K\\)?\\)\\(.*?\\)\\(\033\\[[0-9]*m\\)"
-     2 3
-     ;; Calculate column positions (beg . end) of first grep match on a line
-     ((lambda ()
-	(setq compilation-error-screen-columns nil)
-        (- (match-beginning 4) (match-end 1)))
-      .
-      (lambda () (- (match-end 5) (match-end 1)
-               (- (match-end 4) (match-beginning 4)))))
-     nil 1)
     ("^Binary file \\(.+\\) matches$" 1 nil nil 0 1))
   "Regexp used to match grep hits.  See `compilation-error-regexp-alist'.")