add $pipestatus support

src/input.cpp

@@ -367,10 +367,12 @@ static void input_mapping_execute(const input_mapping_t &m, bool allow_commands)
         // FIXME(snnw): if commands add stuff to input queue (e.g. commandline -f execute), we won't
         // see that until all other commands have also been run.
         int last_status = proc_get_last_status();
+        const auto& last_job_statuses = proc_get_last_job_statuses();
         for (const wcstring &cmd : m.commands) {
             parser_t::principal_parser().eval(cmd, io_chain_t(), TOP);
         }
         proc_set_last_status(last_status);
+        proc_set_last_job_statuses(std::move(last_job_statuses));
         input_common_next_ch(R_NULL);
     } else {
         // Invalid binding, mixed commands and functions.  We would need to execute these one by