pure/base85: align exception type/msg on base85.c brendan mentioned on IRC that b64decode raises a TypeError too, but while the previous exception type may be better in general, it is much easier to make it behave like the related C code and changes nothing for mercurial itself.

parsers: fix refcount bug on corrupt index When we encounter a corrupt index, we "fail" the init but our destructor still gets called. On some systems, this was causing us to attempt to decref a dangling to self->data.