Peff points out that different atom parsers handle the empty
"sub-argument" list differently. An example of this is the format
"%(refname:)".
Since callers often use `string_list_split` (which splits the empty
string with any delimiter as a 1-ary string_list containing the empty
string), this makes handling empty sub-argument strings non-ergonomic.
Let's fix this by assuming that atom parser implementations don't care
about distinguishing between the empty string "%(refname:)" and no
sub-arguments "%(refname)".
Signed-off-by: Taylor Blau <me@xxxxxxxxxxxx>
---
ref-filter.c | 17 ++++++++++++++++-
t/t6300-for-each-ref.sh | 1 +
2 files changed, 17 insertions(+), 1 deletion(-)
diff --git a/ref-filter.c b/ref-filter.c
index bc591f4f3..22be4097a 100644
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -415,8 +415,23 @@ static int parse_ref_filter_atom(const struct ref_format *format,
REALLOC_ARRAY(used_atom, used_atom_cnt);
used_atom[at].name = xmemdupz(atom, ep - atom);
used_atom[at].type = valid_atom[i].cmp_type;
- if (arg)
+ if (arg) {
arg = used_atom[at].name + (arg - atom) + 1;
+ if (!*arg) {
+ /*
+ * string_list_split is often use by atom parsers to
+ * split multiple sub-arguments for inspection.
+ *
+ * Given a string that does not contain a delimiter
+ * (example: ""), string_list_split returns a 1-ary
+ * string_list that requires adding special cases to
+ * atom parsers.
+ *
+ * Thus, treat the empty argument string as NULL.
+ */
+ arg = NULL;
+ }
+ }
memset(&used_atom[at].u, 0, sizeof(used_atom[at].u));
if (valid_atom[i].parser)
valid_atom[i].parser(format, &used_atom[at], arg);
diff --git a/t/t6300-for-each-ref.sh b/t/t6300-for-each-ref.sh
index 2274a4b73..edc1bd8ea 100755
--- a/t/t6300-for-each-ref.sh
+++ b/t/t6300-for-each-ref.sh
@@ -51,6 +51,7 @@ test_atom() {
}
test_atom head refname refs/heads/master
+test_atom head refname: refs/heads/master
test_atom head refname:short master
test_atom head refname:lstrip=1 heads/master
test_atom head refname:lstrip=2 master
--
2.14.1.145.gb3622a4ee
