parsers: introduce headrevsfiltered in C extension
All extensions that have this function do support filtering. The existing
headrevs function may support filtering but we cannot reliably detect whether
it does.
--- a/mercurial/parsers.c Sat Oct 25 21:34:49 2014 -0400
+++ b/mercurial/parsers.c Sun Oct 26 12:14:10 2014 +0100
@@ -2109,7 +2109,9 @@
{"get", (PyCFunction)index_m_get, METH_VARARGS,
"get an index entry"},
{"headrevs", (PyCFunction)index_headrevs, METH_VARARGS,
- "get head revisions"},
+ "get head revisions"}, /* Can do filtering since 3.2 */
+ {"headrevsfiltered", (PyCFunction)index_headrevs, METH_VARARGS,
+ "get filtered head revisions"}, /* Can always do filtering */
{"insert", (PyCFunction)index_insert, METH_VARARGS,
"insert an index entry"},
{"partialmatch", (PyCFunction)index_partialmatch, METH_VARARGS,