Re: bug? in checkout with ambiguous refnames

From

Junio C Hamano <gitster@pobox.com>

Date

Jan 7, 2011, 22:50 UTC

Message-ID

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

In-Reply-To

<20110107195417.GC6175@sigill.intra.peff.net>

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):

 builtin/checkout.c               |    7 +++++++
 t/t2019-checkout-amiguous-ref.sh |   23 ++++++++++++++++++++++-
 2 files changed, 29 insertions(+), 1 deletions(-)

diff --git a/builtin/checkout.c b/builtin/checkout.c
index a54583b..f6fea2f 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -840,6 +840,13 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
 				;
 			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);
 			parse_commit(new.commit);
 			source_tree = new.commit->tree;
 		} else
diff --git a/t/t2019-checkout-amiguous-ref.sh b/t/t2019-checkout-amiguous-ref.sh
index 0981f11..fa1d4e6 100755
--- a/t/t2019-checkout-amiguous-ref.sh
+++ b/t/t2019-checkout-amiguous-ref.sh
@@ -6,8 +6,10 @@ test_description='checkout handling of ambiguous (branch/tag) refs'
 test_expect_success 'setup ambiguous refs' '
 	test_commit branch file &&
 	git branch ambiguity &&
+	git branch vagueness &&
 	test_commit tag file &&
 	git tag ambiguity &&
+	git tag vagueness HEAD:file &&
 	test_commit other file
 '
 
@@ -19,7 +21,7 @@ test_expect_success 'checkout produces ambiguity warning' '
 	grep "warning.*ambiguous" stderr
 '
 
-test_expect_failure 'checkout chooses branch over tag' '
+test_expect_success 'checkout chooses branch over tag' '
 	echo branch >expect &&
 	test_cmp expect file
 '
@@ -29,4 +31,23 @@ test_expect_success 'checkout reports switch to detached HEAD' '
 	! grep "^HEAD is now at" stderr
 '
 
+test_expect_failure 'checkout vague ref succeeds' '
+	git checkout vagueness >stdout 2>stderr &&
+	test_set_prereq VAGUENESS_SUCCESS
+'
+
+test_expect_success VAGUENESS_SUCCESS 'checkout produces ambiguity warning' '
+	grep "warning.*ambiguous" stderr
+'
+
+test_expect_success VAGUENESS_SUCCESS 'checkout chooses branch over tag' '
+	echo branch >expect &&
+	test_cmp expect file
+'
+
+test_expect_success VAGUENESS_SUCCESS 'checkout reports switch to detached HEAD' '
+	grep "Switched to branch" stderr &&
+	! grep "^HEAD is now at" stderr
+'
+
 test_done