Merge branch 'jk/help-unknown-ref-fix'

Improve the code to show args with potential typo that cannot be
interpreted as a commit-ish.

* jk/help-unknown-ref-fix:
  help_unknown_ref(): check for refname ambiguity
  help_unknown_ref(): duplicate collected refnames

1 files changed, 20 insertions, 0 deletions

diff --git a/t/t7600-merge.sh b/t/t7600-merge.sh
index 3e16aaed3b..612ebe7d82 100755
--- a/t/t7600-merge.sh
+++ b/t/t7600-merge.sh
@@ -893,4 +893,24 @@ test_expect_success 'merge --quit' '
 	)
 '
 
+test_expect_success 'merge suggests matching remote refname' '
+	git commit --allow-empty -m not-local &&
+	git update-ref refs/remotes/origin/not-local HEAD &&
+	git reset --hard HEAD^ &&
+
+	# This is white-box testing hackery; we happen to know
+	# that reading packed refs is more picky about the memory
+	# ownership of strings we pass to for_each_ref() callbacks.
+	git pack-refs --all --prune &&
+
+	test_must_fail git merge not-local 2>stderr &&
+	grep origin/not-local stderr
+'
+
+test_expect_success 'suggested names are not ambiguous' '
+	git update-ref refs/heads/origin/not-local HEAD &&
+	test_must_fail git merge not-local 2>stderr &&
+	grep remotes/origin/not-local stderr
+'
+
 test_done