Merge branch 'nd/warn-ambiguous-object-name'

"git cmd <name>", when <name> happens to be a 40-hex string,
directly uses the 40-hex string as an object name, even if a ref
"refs/<some hierarchy>/<name>" exists.  This disambiguation order
is unlikely to change, but we should warn about the ambiguity just
like we warn when more than one refs/ hierachies share the same
name.

* nd/warn-ambiguous-object-name:
  get_sha1: warn about full or short object names that look like refs

1 files changed, 18 insertions, 0 deletions

diff --git a/t/t1512-rev-parse-disambiguation.sh b/t/t1512-rev-parse-disambiguation.sh
index 6b3d797..db22808 100755
--- a/t/t1512-rev-parse-disambiguation.sh
+++ b/t/t1512-rev-parse-disambiguation.sh
@@ -261,4 +261,22 @@ test_expect_success 'rev-parse --disambiguate' '
 	test "$(sed -e "s/^\(.........\).*/\1/" actual | sort -u)" = 000000000
 '
 
+test_expect_success 'ambiguous 40-hex ref' '
+	TREE=$(git mktree </dev/null) &&
+	REF=`git rev-parse HEAD` &&
+	VAL=$(git commit-tree $TREE </dev/null) &&
+	git update-ref refs/heads/$REF $VAL &&
+	test `git rev-parse $REF 2>err` = $REF &&
+	grep "refname.*${REF}.*ambiguous" err
+'
+
+test_expect_success 'ambiguous short sha1 ref' '
+	TREE=$(git mktree </dev/null) &&
+	REF=`git rev-parse --short HEAD` &&
+	VAL=$(git commit-tree $TREE </dev/null) &&
+	git update-ref refs/heads/$REF $VAL &&
+	test `git rev-parse $REF 2>err` = $VAL &&
+	grep "refname.*${REF}.*ambiguous" err
+'
+
 test_done