forge fmt does support stdin, by sending - instead of a path. I assume this is a better approach?
the --check flag causes forge to send an exit code 1 when invalid syntax is found. However, it also causes it to not send any output, resulting in the buffer becoming empty. Removing this flag fixes it, and also makes valid_exit_codes unnecessary
There were two different problems:
forge fmtdoes support stdin, by sending-instead of a path. I assume this is a better approach?--checkflag causesforgeto send an exit code1when invalid syntax is found. However, it also causes it to not send any output, resulting in the buffer becoming empty. Removing this flag fixes it, and also makesvalid_exit_codesunnecessary