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Re: [PATCH] Re: Teach mailinfo to ignore everything before -- >8 -- mark

From
Junio C Hamano <gitster@pobox.com>
Date
Aug 24, 2009, 22:17 UTC
Message-ID
<7v3a7g501e.fsf@alter.siamese.dyndns.org>
In-Reply-To
<20090824071711.GE3526@vidovic>
Nicolas Sebrecht <nicolas.s.dev@gmx.fr> writes:
> ... But isn't the following mark a bit
> too much permissive?
>
> ->8

Yeah, I agree that we should require a bit longer perforation, and perhaps we should tighten the rules a bit, while at the same time not limiting the request to cut to the exact phrase "cut here". As you pointed out, we do not want to be too lenient to allow misidentification, but at the same time it is nicer to be accomodating and treat something like this as a scissors line:

    - - - >8 - - - remove everything above this line - - - >8 - - -

I think we have bikeshedded long enough, so I won't be touching this code any further only to change the definition of what a scissors mark looks like, but here is what I did during lunch break, with another comment added later to hint what s_hdr_data[] stands for after reading response from Don Zickus.

-- >8 --
From: Junio C Hamano <gitster@pobox.com>
Subject: [PATCH] Teach mailinfo to ignore everything before -- >8 -- mark

This teaches mailinfo the scissors -- >8 -- mark; the command ignores everything before it in the message body.

For lefties among us, we also support -- 8< -- ;-)
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 builtin-mailinfo.c  |   71 ++++++++++++++++++++++++++++++++++++++++-
 t/t5100-mailinfo.sh |    2 +-
 t/t5100/info0014    |    5 +++
 t/t5100/msg0014     |    4 ++
 t/t5100/patch0014   |   64 ++++++++++++++++++++++++++++++++++++
 t/t5100/sample.mbox |   89 +++++++++++++++++++++++++++++++++++++++++++++++++++
 6 files changed, 233 insertions(+), 2 deletions(-)
 create mode 100644 t/t5100/info0014
 create mode 100644 t/t5100/msg0014
 create mode 100644 t/t5100/patch0014
diff --git a/builtin-mailinfo.c b/builtin-mailinfo.c
index b0b5d8f..7e09b51 100644
--- a/builtin-mailinfo.c
+++ b/builtin-mailinfo.c
@@ -712,6 +712,56 @@ static inline int patchbreak(const struct strbuf *line)
 	return 0;
 }
 
+static int is_scissors_line(const struct strbuf *line)
+{
+	size_t i, len = line->len;
+	int scissors = 0, gap = 0;
+	int first_nonblank = -1;
+	int last_nonblank = 0, visible, perforation, in_perforation = 0;
+	const char *buf = line->buf;
+
+	for (i = 0; i < len; i++) {
+		if (isspace(buf[i])) {
+			if (in_perforation) {
+				perforation++;
+				gap++;
+			}
+			continue;
+		}
+		last_nonblank = i;
+		if (first_nonblank < 0)
+			first_nonblank = i;
+		if (buf[i] == '-') {
+			in_perforation = 1;
+			perforation++;
+			continue;
+		}
+		if (i + 1 < len &&
+		    (!memcmp(buf + i, ">8", 2) || !memcmp(buf + i, "8<", 2))) {
+			in_perforation = 1;
+			perforation += 2;
+			scissors += 2;
+			i++;
+			continue;
+		}
+		in_perforation = 0;
+	}
+
+	/*
+	 * The mark must be at least 8 bytes long (e.g. "-- >8 --").
+	 * Even though there can be arbitrary cruft on the same line
+	 * (e.g. "cut here"), in order to avoid misidentification, the
+	 * perforation must occupy more than a third of the visible
+	 * width of the line, and dashes and scissors must occupy more
+	 * than half of the perforation.
+	 */
+
+	visible = last_nonblank - first_nonblank + 1;
+	return (scissors && 8 <= visible &&
+		visible < perforation * 3 &&
+		gap * 2 < perforation);
+}
+
 static int handle_commit_msg(struct strbuf *line)
 {
 	static int still_looking = 1;
@@ -723,7 +773,8 @@ static int handle_commit_msg(struct strbuf *line)
 		strbuf_ltrim(line);
 		if (!line->len)
 			return 0;
-		if ((still_looking = check_header(line, s_hdr_data, 0)) != 0)
+		still_looking = check_header(line, s_hdr_data, 0);
+		if (still_looking)
 			return 0;
 	}
 
@@ -731,6 +782,24 @@ static int handle_commit_msg(struct strbuf *line)
 	if (metainfo_charset)
 		convert_to_utf8(line, charset.buf);
 
+	if (is_scissors_line(line)) {
+		int i;
+		rewind(cmitmsg);
+		ftruncate(fileno(cmitmsg), 0);
+		still_looking = 1;
+
+		/*
+		 * We may have already read "secondary headers"; purge
+		 * them to give ourselves a clean restart.
+		 */
+		for (i = 0; header[i]; i++) {
+			if (s_hdr_data[i])
+				strbuf_release(s_hdr_data[i]);
+			s_hdr_data[i] = NULL;
+		}
+		return 0;
+	}
+
 	if (patchbreak(line)) {
 		fclose(cmitmsg);
 		cmitmsg = NULL;
diff --git a/t/t5100-mailinfo.sh b/t/t5100-mailinfo.sh
index e70ea94..e848556 100755
--- a/t/t5100-mailinfo.sh
+++ b/t/t5100-mailinfo.sh
@@ -11,7 +11,7 @@ test_expect_success 'split sample box' \
 	'git mailsplit -o. "$TEST_DIRECTORY"/t5100/sample.mbox >last &&
 	last=`cat last` &&
 	echo total is $last &&
-	test `cat last` = 13'
+	test `cat last` = 14'
 
 for mail in `echo 00*`
 do
diff --git a/t/t5100/info0014 b/t/t5100/info0014
new file mode 100644
index 0000000..ab9c8d0
--- /dev/null
+++ b/t/t5100/info0014
@@ -0,0 +1,5 @@
+Author: Junio C Hamano
+Email: gitster@pobox.com
+Subject: Teach mailinfo to ignore everything before -- >8 -- mark
+Date: Thu, 20 Aug 2009 17:18:22 -0700
+
diff --git a/t/t5100/msg0014 b/t/t5100/msg0014
new file mode 100644
index 0000000..259c6a4
--- /dev/null
+++ b/t/t5100/msg0014
@@ -0,0 +1,4 @@
+This teaches mailinfo the scissors -- >8 -- mark; the command ignores
+everything before it in the message body.
+
+Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/t/t5100/patch0014 b/t/t5100/patch0014
new file mode 100644
index 0000000..124efd2
--- /dev/null
+++ b/t/t5100/patch0014
@@ -0,0 +1,64 @@
+---
+ builtin-mailinfo.c |   37 ++++++++++++++++++++++++++++++++++++-
+ 1 files changed, 36 insertions(+), 1 deletions(-)
+
+diff --git a/builtin-mailinfo.c b/builtin-mailinfo.c
+index b0b5d8f..461c47e 100644
+--- a/builtin-mailinfo.c
++++ b/builtin-mailinfo.c
+@@ -712,6 +712,34 @@ static inline int patchbreak(const struct strbuf *line)
+ 	return 0;
+ }
+ 
++static int scissors(const struct strbuf *line)
++{
++	size_t i, len = line->len;
++	int scissors_dashes_seen = 0;
++	const char *buf = line->buf;
++
++	for (i = 0; i < len; i++) {
++		if (isspace(buf[i]))
++			continue;
++		if (buf[i] == '-') {
++			scissors_dashes_seen |= 02;
++			continue;
++		}
++		if (i + 1 < len && !memcmp(buf + i, ">8", 2)) {
++			scissors_dashes_seen |= 01;
++			i++;
++			continue;
++		}
++		if (i + 7 < len && !memcmp(buf + i, "cut here", 8)) {
++			i += 7;
++			continue;
++		}
++		/* everything else --- not scissors */
++		break;
++	}
++	return scissors_dashes_seen == 03;
++}
++
+ static int handle_commit_msg(struct strbuf *line)
+ {
+ 	static int still_looking = 1;
+@@ -723,10 +751,17 @@ static int handle_commit_msg(struct strbuf *line)
+ 		strbuf_ltrim(line);
+ 		if (!line->len)
+ 			return 0;
+-		if ((still_looking = check_header(line, s_hdr_data, 0)) != 0)
++		still_looking = check_header(line, s_hdr_data, 0);
++		if (still_looking)
+ 			return 0;
+ 	}
+ 
++	if (scissors(line)) {
++		fseek(cmitmsg, 0L, SEEK_SET);
++		still_looking = 1;
++		return 0;
++	}
++
+ 	/* normalize the log message to UTF-8. */
+ 	if (metainfo_charset)
+ 		convert_to_utf8(line, charset.buf);
+-- 
+1.6.4.1
diff --git a/t/t5100/sample.mbox b/t/t5100/sample.mbox
index c3074ac..13fa4ae 100644
--- a/t/t5100/sample.mbox
+++ b/t/t5100/sample.mbox
@@ -561,3 +561,92 @@ From: <a.u.thor@example.com> (A U Thor)
 Date: Fri, 9 Jun 2006 00:44:16 -0700
 Subject: [PATCH] a patch
 
+From nobody Mon Sep 17 00:00:00 2001
+From: Junio Hamano <junkio@cox.net>
+Date: Thu, 20 Aug 2009 17:18:22 -0700
+Subject: Why doesn't git-am does not like >8 scissors mark?
+
+Subject: [PATCH] BLAH ONE
+
+In real life, we will see a discussion that inspired this patch
+discussing related and unrelated things around >8 scissors mark
+in this part of the message.
+
+Subject: [PATCH] BLAH TWO
+
+And then we will see the scissors.
+
+ This line is not a scissors mark -- >8 -- but talks about it.
+ - - >8 - - please remove everything above this line - - >8 - -
+
+Subject: [PATCH] Teach mailinfo to ignore everything before -- >8 -- mark
+From: Junio C Hamano <gitster@pobox.com>
+
+This teaches mailinfo the scissors -- >8 -- mark; the command ignores
+everything before it in the message body.
+
+Signed-off-by: Junio C Hamano <gitster@pobox.com>
+---
+ builtin-mailinfo.c |   37 ++++++++++++++++++++++++++++++++++++-
+ 1 files changed, 36 insertions(+), 1 deletions(-)
+
+diff --git a/builtin-mailinfo.c b/builtin-mailinfo.c
+index b0b5d8f..461c47e 100644
+--- a/builtin-mailinfo.c
++++ b/builtin-mailinfo.c
+@@ -712,6 +712,34 @@ static inline int patchbreak(const struct strbuf *line)
+ 	return 0;
+ }
+ 
++static int scissors(const struct strbuf *line)
++{
++	size_t i, len = line->len;
++	int scissors_dashes_seen = 0;
++	const char *buf = line->buf;
++
++	for (i = 0; i < len; i++) {
++		if (isspace(buf[i]))
++			continue;
++		if (buf[i] == '-') {
++			scissors_dashes_seen |= 02;
++			continue;
++		}
++		if (i + 1 < len && !memcmp(buf + i, ">8", 2)) {
++			scissors_dashes_seen |= 01;
++			i++;
++			continue;
++		}
++		if (i + 7 < len && !memcmp(buf + i, "cut here", 8)) {
++			i += 7;
++			continue;
++		}
++		/* everything else --- not scissors */
++		break;
++	}
++	return scissors_dashes_seen == 03;
++}
++
+ static int handle_commit_msg(struct strbuf *line)
+ {
+ 	static int still_looking = 1;
+@@ -723,10 +751,17 @@ static int handle_commit_msg(struct strbuf *line)
+ 		strbuf_ltrim(line);
+ 		if (!line->len)
+ 			return 0;
+-		if ((still_looking = check_header(line, s_hdr_data, 0)) != 0)
++		still_looking = check_header(line, s_hdr_data, 0);
++		if (still_looking)
+ 			return 0;
+ 	}
+ 
++	if (scissors(line)) {
++		fseek(cmitmsg, 0L, SEEK_SET);
++		still_looking = 1;
++		return 0;
++	}
++
+ 	/* normalize the log message to UTF-8. */
+ 	if (metainfo_charset)
+ 		convert_to_utf8(line, charset.buf);
+-- 
+1.6.4.1
-- 
1.6.4.1
Previous: Nicolas SebrechtNext: Nicolas Sebrecht
Message 33 of 63 in “Help/Advice needed on diff bug in xutils.c”
  1. Thell FowlerAug 4, 2009
  2. Johannes SchindelinAug 5, 2009
  3. Thell FowlerAug 10, 2009
  4. Add diff tests for trailing-space and now newlineThell Fowler, Aug 12, 2009
  5. 0/6 Series to correct xutils incomplete line handling.Thell Fowler, Aug 19, 2009
  6. Thell FowlerAug 21, 2009
  7. Alex RiesenAug 21, 2009
  8. Thell FowlerAug 22, 2009
  9. 0/6 improvements for trailing-space processing on incomplete linesThell Fowler, Aug 23, 2009
  10. 1/6 Add supplemental test for trailing-whitespace on incomplete linesThell Fowler, Aug 23, 2009
  11. 2/6 xutils: fix hash with whitespace on incomplete lineThell Fowler, Aug 23, 2009
  12. Junio C HamanoAug 23, 2009
  13. Thell FowlerAug 23, 2009
  14. 3/6 xutils: fix ignore-all-space on incomplete lineThell Fowler, Aug 23, 2009
  15. Junio C HamanoAug 23, 2009
  16. Nanako ShiraishiAug 23, 2009
  17. Junio C HamanoAug 23, 2009
  18. Nanako ShiraishiAug 23, 2009
  19. Junio C HamanoAug 23, 2009
  20. Thell FowlerAug 23, 2009
  21. Junio C HamanoAug 23, 2009
  22. Teach mailinfo to ignore everything before -- >8 -- markNicolas Sebrecht, Aug 24, 2009
  23. Junio C HamanoAug 24, 2009
  24. Junio C HamanoAug 24, 2009
  25. Re: Teach mailinfo to ignore everything before -- >8 -- markNicolas Sebrecht, Aug 24, 2009
  26. Junio C HamanoAug 24, 2009
  27. Re: Teach mailinfo to ignore everything before -- >8 -- markNicolas Sebrecht, Aug 24, 2009
  28. Don ZickusAug 24, 2009
  29. Junio C HamanoAug 24, 2009
  30. Nanako ShiraishiAug 24, 2009
  31. Re: Teach mailinfo to ignore everything before -- >8 -- markNicolas Sebrecht, Aug 24, 2009
  32. Re: Teach mailinfo to ignore everything before -- >8 -- markNicolas Sebrecht, Aug 24, 2009
  33. Junio C HamanoAug 24, 2009
  34. Nicolas SebrechtAug 25, 2009
  35. Junio C HamanoAug 26, 2009
  36. Junio C HamanoAug 26, 2009
  37. Re: Teach mailinfo to ignore everything before -- >8 -- markNicolas Sebrecht, Aug 26, 2009
  38. Jakub NarebskiAug 26, 2009
  39. Johannes SchindelinAug 26, 2009
  40. Junio C HamanoAug 27, 2009
  41. Johannes SchindelinAug 27, 2009
  42. Junio C HamanoAug 26, 2009
  43. Re: Teach mailinfo to ignore everything before -- >8 -- markNicolas Sebrecht, Aug 26, 2009
  44. Nanako ShiraishiAug 24, 2009
  45. Thell FowlerAug 23, 2009
  46. Junio C HamanoAug 23, 2009
  47. Thell FowlerAug 23, 2009
  48. Junio C HamanoAug 23, 2009
  49. Thell FowlerAug 24, 2009
  50. Junio C HamanoAug 24, 2009
  51. Thell FowlerAug 24, 2009
  52. Thell FowlerAug 25, 2009
  53. 4/6 xutils: fix ignore-space-change on incomplete lineThell Fowler, Aug 23, 2009
  54. 5/6 xutils: fix ignore-space-at-eol on incomplete lineThell Fowler, Aug 23, 2009
  55. 6/6 t4015: add tests for trailing-space on incomplete lineThell Fowler, Aug 23, 2009
  56. 1/6 Add supplemental test for trailing-whitespace on incomplete lines.Thell Fowler, Aug 19, 2009
  57. 2/6 Make xdl_hash_record_with_whitespace ignore eofThell Fowler, Aug 19, 2009
  58. 3/6 Make diff -w handle trailing-spaces on incomplete lines.Thell Fowler, Aug 19, 2009
  59. Thell FowlerAug 20, 2009
  60. 4/6 Make diff -b handle trailing-spaces on incomplete lines.Thell Fowler, Aug 19, 2009
  61. 5/6 Make diff --ignore-space-at-eol handle incomplete lines.Thell Fowler, Aug 19, 2009
  62. 6/6 Add diff tests for trailing-space on incomplete linesThell Fowler, Aug 19, 2009
  63. Junio C HamanoAug 26, 2009

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