Re: bug? in checkout with ambiguous refnames

From

Junio C Hamano <gitster@pobox.com>

Date

Jan 7, 2011, 23:17 UTC

Message-ID

<7vipy0483h.fsf@alter.siamese.dyndns.org>

In-Reply-To

<7vsjx449bv.fsf@alter.siamese.dyndns.org>

Junio C Hamano <gitster@pobox.com> writes:

> Jeff King <peff@peff.net> writes:
>
>> Here is the test script I worked out which shows the issue (and checks
>> that the right messages are shown to the user):
>
> This is a band-aid that is not quite right (even though it passes the
> tests).  Attempting to check out a branch "frotz" in a repository with a
> tag "frotz" that point at a non-commit would still fail, which is not a
> new problem.
>
>
>  builtin/checkout.c               |    7 +++++++
>  t/t2019-checkout-amiguous-ref.sh |   23 ++++++++++++++++++++++-
>  2 files changed, 29 insertions(+), 1 deletions(-)

 builtin/checkout.c               |   26 ++++++++++----------------
 t/t2019-checkout-amiguous-ref.sh |    2 +-
 2 files changed, 11 insertions(+), 17 deletions(-)

diff --git a/builtin/checkout.c b/builtin/checkout.c
index f6fea2f..48e547b 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -832,25 +832,19 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
 		argc--;
 
 		new.name = arg;
-		if ((new.commit = lookup_commit_reference_gently(rev, 1))) {
-			setup_branch_path(&new);
+		setup_branch_path(&new);
 
-			if ((check_ref_format(new.path) == CHECK_REF_FORMAT_OK) &&
-			    resolve_ref(new.path, rev, 1, NULL))
-				;
-			else
-				new.path = NULL;
-			if (hashcmp(new.commit->object.sha1, rev))
-				/*
-				 * Yikes, arg is an ambiguous and higher
-				 * precedence SHA-1 expression than the
-				 * branch name
-				 */
-				new.commit = lookup_commit_reference_gently(rev, 1);
+		if ((check_ref_format(new.path) != CHECK_REF_FORMAT_OK) ||
+		    !resolve_ref(new.path, rev, 1, NULL))
+			new.path = NULL; /* not an existing branch */
+
+		if (!(new.commit = lookup_commit_reference_gently(rev, 1))) {
+			/* not a commit */
+			source_tree = parse_tree_indirect(rev);
+		} else {
 			parse_commit(new.commit);
 			source_tree = new.commit->tree;
-		} else
-			source_tree = parse_tree_indirect(rev);
+		}
 
 		if (!source_tree)                   /* case (1): want a tree */
 			die("reference is not a tree: %s", arg);
diff --git a/t/t2019-checkout-amiguous-ref.sh b/t/t2019-checkout-amiguous-ref.sh
index fa1d4e6..e2b330b 100755
--- a/t/t2019-checkout-amiguous-ref.sh
+++ b/t/t2019-checkout-amiguous-ref.sh
@@ -31,7 +31,7 @@ test_expect_success 'checkout reports switch to detached HEAD' '
 	! grep "^HEAD is now at" stderr
 '
 
-test_expect_failure 'checkout vague ref succeeds' '
+test_expect_success 'checkout vague ref succeeds' '
 	git checkout vagueness >stdout 2>stderr &&
 	test_set_prereq VAGUENESS_SUCCESS
 '