Grep related fixes.

* etc/grep.txt: Add `eval' to the Local Variables section that
emulates `grep-filter'.

* lisp/progmodes/grep.el (grep-filter): Avoid incomplete processing by
keeping point where processing of grep matches begins, and
continue to delete remaining escape sequences from the same point.
(grep-filter): Make leading zero optional in "0?1;31m" because
git-grep emits "\033[1;31m" escape sequences unlike expected
"\033[01;31m" as GNU Grep does.
(grep-process-setup): Replace obsolete "ml=" with newer "sl=".

Fixes: debbugs:9408

1 files changed, 5 insertions, 4 deletions

diff --git a/lisp/progmodes/grep.el b/lisp/progmodes/grep.el
index 709f01444bf..eeebcc6648f 100644
--- a/lisp/progmodes/grep.el
+++ b/lisp/progmodes/grep.el
@@ -459,7 +459,7 @@ Set up `compilation-exit-message-function' and run `grep-setup-hook'."
     ;; GREP_COLOR is used in GNU grep 2.5.1, but deprecated in later versions
     (setenv "GREP_COLOR" "01;31")
     ;; GREP_COLORS is used in GNU grep 2.5.2 and later versions
-    (setenv "GREP_COLORS" "mt=01;31:fn=:ln=:bn=:se=:ml=:cx=:ne"))
+    (setenv "GREP_COLORS" "mt=01;31:fn=:ln=:bn=:se=:sl=:cx=:ne"))
   (set (make-local-variable 'compilation-exit-message-function)
        (lambda (status code msg)
          (if (eq status 'exit)
@@ -480,20 +480,21 @@ Set up `compilation-exit-message-function' and run `grep-setup-hook'."
 This function is called from `compilation-filter-hook'."
   (save-excursion
     (forward-line 0)
-    (let ((end (point)))
+    (let ((end (point)) beg)
       (goto-char compilation-filter-start)
       (forward-line 0)
+      (setq beg (point))
       ;; Only operate on whole lines so we don't get caught with part of an
       ;; escape sequence in one chunk and the rest in another.
       (when (< (point) end)
         (setq end (copy-marker end))
         ;; Highlight grep matches and delete marking sequences.
-        (while (re-search-forward "\033\\[01;31m\\(.*?\\)\033\\[[0-9]*m" end 1)
+        (while (re-search-forward "\033\\[0?1;31m\\(.*?\\)\033\\[[0-9]*m" end 1)
           (replace-match (propertize (match-string 1)
                                      'face nil 'font-lock-face grep-match-face)
                          t t))
         ;; Delete all remaining escape sequences
-        (goto-char compilation-filter-start)
+        (goto-char beg)
         (while (re-search-forward "\033\\[[0-9;]*[mK]" end 1)
           (replace-match "" t t))))))