Subject: Re: [PATCH] Make sure an autogenerated version has at least four parts

From: Sam Vilain <[email-masked]>
Date: Fri, 25 May 2007 13:33:21 +1200

Martin Waitz wrote:
> hoi :)
> 
> On Mon, May 21, 2007 at 02:52:21PM +1200, Sam Vilain wrote:
>> Otherwise, a custom "v1.5.2.42.gd00b" is considered newer than a
>> "v1.5.2.1.69.gcafe".
> 
> or just use git describe output without replacing "-" with "."?
> 

dpkg uses "-" in version numbers for its own uses - to delimit the
packager's packaging version from the software version.  The change I
posted keeps original behaviour - just fills out the .0's.

Perhaps the munging should go in git-describe instead?

Subject: [PATCH] describe: add --levels option

Some projects might want git describe to always give a result that
has a given number of version levels.  ie, if you say --levels=4
and describe finds a name like 'v1.5.2', the result will be 'v1.5.2.0'.

This does mean that on exact tag matches, the returned version
is not a resolvable ref - but that is probably caveat emptor.

Signed-off-by: Sam Vilain <[email-masked]>
---
 builtin-describe.c  |   50 ++++++++++++++++++++++++++++++++++++++++++++++----
 t/t6120-describe.sh |    8 ++++++++
 2 files changed, 54 insertions(+), 4 deletions(-)

diff --git a/builtin-describe.c b/builtin-describe.c
index 165917e..05eabc5 100644
--- a/builtin-describe.c
+++ b/builtin-describe.c
@@ -15,6 +15,7 @@ static int all;	/* Default to annotated tags only */
 static int tags;	/* But allow any tags if --tags is specified */
 static int abbrev = DEFAULT_ABBREV;
 static int max_candidates = 10;
+static int num_levels = 0;
 
 struct commit_name {
 	int prio; /* annotated tag = 2, tag = 1, head = 0 */
@@ -134,6 +135,7 @@ static void describe(const char *arg, int last_one)
 	struct possible_tag all_matches[MAX_TAGS];
 	unsigned int match_cnt = 0, annotated_cnt = 0, cur_match;
 	unsigned long seen_commits = 0;
+	char* chosen;
 
 	if (get_sha1(arg, sha1))
 		die("Not a valid object name %s", arg);
@@ -148,8 +150,9 @@ static void describe(const char *arg, int last_one)
 
 	n = cmit->util;
 	if (n) {
-		printf("%s\n", n->path);
-		return;
+		chosen = n->path;
+		abbrev = 0;
+		goto show;
 	}
 
 	if (debug)
@@ -228,10 +231,44 @@ static void describe(const char *arg, int last_one)
 				sha1_to_hex(gave_up_on->object.sha1));
 		}
 	}
+
+	chosen = all_matches[0].name->path;
+
+	/* make the described version have the desired number of
+	 * levels in it */
+ show:
+	if (num_levels) {
+		int found = 1;
+		char* idx = chosen;
+		int i;
+		while ((idx = index(idx, '.'))) {
+			found++;
+			idx++;
+		}
+		if (found > num_levels) {
+			idx = chosen;
+			for (i = 0; i < num_levels; i++) {
+				if (i)
+					idx++;
+				idx = index(idx, '.');
+			}
+			*idx = '\0';
+		}
+		else if (found < num_levels) {
+			int extra = 2 * (num_levels - found);
+			char* new = xmalloc(strlen(chosen) + extra + 1);
+			chosen = strcpy(new, chosen);
+			while (found < num_levels) {
+				strcat(chosen, ".0");
+				found++;
+			}
+		}
+	}
+
 	if (abbrev == 0)
-		printf("%s\n", all_matches[0].name->path );
+		printf("%s\n", chosen);
 	else
-		printf("%s-%d-g%s\n", all_matches[0].name->path,
+		printf("%s-%d-g%s\n", chosen,
 		       all_matches[0].depth,
 		       find_unique_abbrev(cmit->object.sha1, abbrev));
 
@@ -266,6 +303,11 @@ int cmd_describe(int argc, const char **argv, const char *prefix)
 			else if (max_candidates > MAX_TAGS)
 				max_candidates = MAX_TAGS;
 		}
+		else if (!prefixcmp(arg, "--levels=")) {
+			num_levels = strtoul(arg + 9, NULL, 10);
+			if (num_levels < 0) 
+				num_levels = 0;
+		}
 		else
 			usage(describe_usage);
 	}
diff --git a/t/t6120-describe.sh b/t/t6120-describe.sh
index 3e9edda..0336ddd 100755
--- a/t/t6120-describe.sh
+++ b/t/t6120-describe.sh
@@ -33,6 +33,7 @@ test_expect_success setup '
 
 	test_tick &&
 	echo two >file && git-add file && git-commit -m second &&
+	git-tag -a -m v1.1 v1.1 &&
 	two=$(git-rev-parse HEAD) &&
 
 	test_tick &&
@@ -94,4 +95,11 @@ check_describe D-* --tags HEAD^^
 check_describe A-* --tags HEAD^^2
 check_describe B --tags HEAD^^2^
 
+check_describe A.0-* --tags --levels=2 HEAD
+check_describe A.0.0-* --tags --levels=3 HEAD
+check_describe v1 --tags --levels=1 v1.1
+check_describe v1.1 --tags --levels=2 v1.1
+check_describe v1.1.0 --tags --levels=3 v1.1
+check_describe v1-* --tags --levels=1 A^1
+
 test_done
-- 
1.5.2.0.45.gfea6d-dirty