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[PATCH 2/3] merge: fix incorrect merge message for ambiguous tag/branch

From
Jeff King <peff@peff.net>
Date
Aug 9, 2009, 10:02 UTC
Message-ID
<20090809100224.GB25231@coredump.intra.peff.net>
In-Reply-To
<20090809100045.GA25197@coredump.intra.peff.net>

If we have both a tag and a branch named "foo", then calling "git merge foo" will warn about the ambiguous ref, but merge the tag.

When generating the commit message, though, we simply checked whether "refs/heads/foo" existed, and if it did, assumed it was a branch. This led to the statement "Merge branch 'foo'" in the commit message, which is quite wrong.

Instead, we should use dwim_ref to find the actual ref used, and describe it appropriately.

In addition to the test in t7608, we must also tweak the expected output of t4202, which was accidentally triggering this bug.

Signed-off-by: Jeff King <peff@peff.net>
---
 builtin-merge.c           |   15 +++++++--------
 t/t4202-log.sh            |    4 ++--
 t/t7608-merge-messages.sh |    2 +-
 3 files changed, 10 insertions(+), 11 deletions(-)
diff --git a/builtin-merge.c b/builtin-merge.c
index 82b5466..f7db148 100644
--- a/builtin-merge.c
+++ b/builtin-merge.c
@@ -358,6 +358,7 @@ static void merge_name(const char *remote, struct strbuf *msg)
 	struct strbuf buf = STRBUF_INIT;
 	struct strbuf bname = STRBUF_INIT;
 	const char *ptr;
+	char *found_ref;
 	int len, early;
 
 	strbuf_branchname(&bname, remote);
@@ -368,14 +369,12 @@ static void merge_name(const char *remote, struct strbuf *msg)
 	if (!remote_head)
 		die("'%s' does not point to a commit", remote);
 
-	strbuf_addstr(&buf, "refs/heads/");
-	strbuf_addstr(&buf, remote);
-	resolve_ref(buf.buf, branch_head, 0, NULL);
-
-	if (!hashcmp(remote_head->sha1, branch_head)) {
-		strbuf_addf(msg, "%s\t\tbranch '%s' of .\n",
-			sha1_to_hex(branch_head), remote);
-		goto cleanup;
+	if (dwim_ref(remote, strlen(remote), branch_head, &found_ref) > 0) {
+		if (!prefixcmp(found_ref, "refs/heads/")) {
+			strbuf_addf(msg, "%s\t\tbranch '%s' of .\n",
+				    sha1_to_hex(branch_head), remote);
+			goto cleanup;
+		}
 	}
 
 	/* See if remote matches <name>^^^.. or <name>~<number> */
diff --git a/t/t4202-log.sh b/t/t4202-log.sh
index 48e0088..1e952ca 100755
--- a/t/t4202-log.sh
+++ b/t/t4202-log.sh
@@ -320,11 +320,11 @@ test_expect_success 'set up more tangled history' '
 '
 
 cat > expect <<\EOF
-*   Merge branch 'reach'
+*   Merge commit 'reach'
 |\
 | \
 |  \
-*-. \   Merge branches 'octopus-a' and 'octopus-b'
+*-. \   Merge commit 'octopus-a'; commit 'octopus-b'
 |\ \ \
 * | | | seventh
 | | * | octopus-b
diff --git a/t/t7608-merge-messages.sh b/t/t7608-merge-messages.sh
index 9d10583..81ced8a 100755
--- a/t/t7608-merge-messages.sh
+++ b/t/t7608-merge-messages.sh
@@ -38,7 +38,7 @@ test_expect_success 'merge tag' '
 	check_oneline "Merge commit Qtag-1Q"
 '
 
-test_expect_failure 'ambiguous tag' '
+test_expect_success 'ambiguous tag' '
 	git checkout -b ambiguous master &&
 	test_commit ambiguous &&
 	git checkout master &&
-- 
1.6.4.178.g7a987
Previous: Jeff KingNext: Jeff King
Message 8 of 12 in “merge: indicate remote tracking branches in merge message”
  1. merge: indicate remote tracking branches in merge messageJeff King, Aug 9, 2009
  2. Jeff KingAug 9, 2009
  3. Junio C HamanoAug 9, 2009
  4. Jeff KingAug 9, 2009
  5. Jeff KingAug 9, 2009
  6. Jeff KingAug 9, 2009
  7. 1/3 add tests for merge message headingsJeff King, Aug 9, 2009
  8. 2/3 merge: fix incorrect merge message for ambiguous tag/branchJeff King, Aug 9, 2009
  9. 3/3 merge: indicate remote tracking branches in merge messageJeff King, Aug 9, 2009
  10. Jeff KingAug 9, 2009
  11. Junio C HamanoAug 9, 2009
  12. Jeff KingAug 9, 2009

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