git log -- :/a
'
+# This differs from the ":/a" check above in that :/in looks like a pathspec,
+# but doesn't match an actual file.
+test_expect_success '"git log :/in" should not be ambiguous' '
+ git log :/in
+'
+
test_expect_success '"git log :" should be ambiguous' '
test_must_fail git log : 2>error &&
test_i18ngrep ambiguous error