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[PATCH 6/5] Fix parsing of @{-1}@{1}

From
Johannes Schindelin <johannes.schindelin@gmx.de>
Date
Jan 17, 2009, 18:08 UTC
Message-ID
<alpine.DEB.1.00.0901171907530.3586@pacific.mpi-cbg.de>
In-Reply-To
<1232208597-29249-6-git-send-email-trast@student.ethz.ch>

To do that, Git no longer looks forward for the '@{' corresponding to the closing '}' but backward, and dwim_ref() as well as dwim_log() learnt about the @{-<N>} notation.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
	The modifications of dwim_ref() and dwim_log() are probably
	more important than the issue I tried to fix...
 sha1_name.c               |   25 ++++++++++++++++++++++++-
 t/t1505-rev-parse-last.sh |    2 +-
 2 files changed, 25 insertions(+), 2 deletions(-)
diff --git a/sha1_name.c b/sha1_name.c
index 306d04b..ee0c456 100644
--- a/sha1_name.c
+++ b/sha1_name.c
@@ -240,8 +240,28 @@ static int ambiguous_path(const char *path, int len)
 	return slash;
 }
 
+/*
+ * *string and *len will only be substituted, and *string returned (for
+ * later free()ing) if the string passed in is of the form @{-<n>}.
+ */
+static char *substitute_nth_last_branch(const char **string, int *len)
+{
+	struct strbuf buf = STRBUF_INIT;
+	int ret = interpret_nth_last_branch(*string, &buf);
+
+	if (ret == *len) {
+		size_t size;
+		*string = strbuf_detach(&buf, &size);
+		*len = size;
+		return (char *)*string;
+	}
+
+	return NULL;
+}
+
 int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
 {
+	char *last_branch = substitute_nth_last_branch(&str, &len);
 	const char **p, *r;
 	int refs_found = 0;
 
@@ -261,11 +281,13 @@ int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref)
 				break;
 		}
 	}
+	free(last_branch);
 	return refs_found;
 }
 
 int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
 {
+	char *last_branch = substitute_nth_last_branch(&str, &len);
 	const char **p;
 	int logs_found = 0;
 
@@ -296,6 +318,7 @@ int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
 		if (!warn_ambiguous_refs)
 			break;
 	}
+	free(last_branch);
 	return logs_found;
 }
 
@@ -314,7 +337,7 @@ static int get_sha1_basic(const char *str, int len, unsigned char *sha1)
 	/* basic@{time or number or -number} format to query ref-log */
 	reflog_len = at = 0;
 	if (str[len-1] == '}') {
-		for (at = 0; at < len - 1; at++) {
+		for (at = len-2; at >= 0; at--) {
 			if (str[at] == '@' && str[at+1] == '{') {
 				reflog_len = (len-1) - (at+2);
 				len = at;
diff --git a/t/t1505-rev-parse-last.sh b/t/t1505-rev-parse-last.sh
index 72e8322..2d6b31e 100755
--- a/t/t1505-rev-parse-last.sh
+++ b/t/t1505-rev-parse-last.sh
@@ -58,7 +58,7 @@ test_expect_success '@{-1}^2 works' '
 	test_rev_equivalent side^2 @{-1}^2
 '
 
-test_expect_failure '@{-1}@{1} works' '
+test_expect_success '@{-1}@{1} works' '
 	test_rev_equivalent side@{1} @{-1}@{1}
 '
 
-- 
1.6.1.332.g9a59d
Previous: Thomas RastNext: Junio C Hamano
Message 21 of 56 in “N-th last checked out branch”
  1. 0/6 N-th last checked out branchThomas Rast, Jan 17, 2009
  2. 1/6 reflog: refactor parsing and checkingThomas Rast, Jan 17, 2009
  3. 2/6 reflog: refactor log open+mmapThomas Rast, Jan 17, 2009
  4. 3/6 reflog: make for_each_reflog_ent use mmapThomas Rast, Jan 17, 2009
  5. 4/6 reflog: add backwards iteratorThomas Rast, Jan 17, 2009
  6. 5/6 sha1_name: implement @{-N} syntax for N-th last checked outThomas Rast, Jan 17, 2009
  7. 6/6 checkout: implement '@{-N}' and '-' special abbreviationsThomas Rast, Jan 17, 2009
  8. Johannes SchindelinJan 17, 2009
  9. Johannes SchindelinJan 17, 2009
  10. Johannes SchindelinJan 17, 2009
  11. Thomas RastJan 17, 2009
  12. 1/2 sha1_name: implement @{-N} syntax for N-th last checked outThomas Rast, Jan 17, 2009
  13. 2/2 checkout: implement '@{-N}' and '-' special abbreviationsThomas Rast, Jan 17, 2009
  14. interpret_nth_last_branch(): avoid traversing the reflogs twiceJohannes Schindelin, Jan 17, 2009
  15. 0/5 N-th last checked out branchThomas Rast, Jan 17, 2009
  16. 1/5 checkout: implement "@{-N}" shortcut name for N-th last branchThomas Rast, Jan 17, 2009
  17. 2/5 sha1_name: tweak @{-N} lookupThomas Rast, Jan 17, 2009
  18. 3/5 sha1_name: support @{-N} syntax in get_sha1()Thomas Rast, Jan 17, 2009
  19. 4/5 checkout: implement "-" abbreviation, add docs and testsThomas Rast, Jan 17, 2009
  20. 5/5 interpret_nth_last_branch(): avoid traversing the reflogs twiceThomas Rast, Jan 17, 2009
  21. 6/5 Fix parsing of @{-1}@{1}Johannes Schindelin, Jan 17, 2009
  22. Junio C HamanoJan 17, 2009
  23. Johannes SchindelinJan 17, 2009
  24. Junio C HamanoJan 17, 2009
  25. Johannes SchindelinJan 17, 2009
  26. Junio C HamanoJan 17, 2009
  27. Junio C HamanoJan 18, 2009
  28. Johannes SchindelinJan 17, 2009
  29. Junio C HamanoJan 17, 2009
  30. Johannes SchindelinJan 17, 2009
  31. Junio C HamanoJan 18, 2009
  32. Johannes SchindelinJan 18, 2009
  33. Junio C HamanoJan 18, 2009
  34. Johannes SchindelinJan 18, 2009
  35. Junio C HamanoJan 19, 2009
  36. Junio C HamanoJan 19, 2009
  37. Johannes SchindelinJan 19, 2009
  38. Thomas RastJan 20, 2009
  39. Johannes SchindelinJan 20, 2009
  40. Thomas RastJan 20, 2009
  41. interpret_nth_last_branch(): plug small memleakJunio C Hamano, Jan 20, 2009
  42. Johannes SchindelinJan 20, 2009
  43. Introduce for_each_recent_reflog_ent().Junio C Hamano, Jan 20, 2009
  44. Johannes SchindelinJan 20, 2009
  45. Junio C HamanoJan 20, 2009
  46. Fix invalid memory accessJohannes Schindelin, Jan 21, 2009
  47. Junio C HamanoJan 21, 2009
  48. Thomas RastJan 21, 2009
  49. Junio C HamanoJan 21, 2009
  50. Johannes SchindelinJan 21, 2009
  51. Thomas RastJan 24, 2009
  52. t1505: remove debugging cruftThomas Rast, Jan 24, 2009
  53. Junio C HamanoJan 25, 2009
  54. Johannes SchindelinJan 21, 2009
  55. @{-<n>}: avoid crash with corrupt reflogJohannes Schindelin, Jan 19, 2009
  56. Johannes SchindelinJan 19, 2009

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