Hi Tom, Thanks for your comments, I do forget create type shell. But even if I add this line still does not work. Here is the commit that can demo my bug ( https://github.com/charles-cui/pg_thrift/commit/8b43f3e2172f4a1b4e61211f7d76b061a90c38f7 ) To see it, download the repo and do make install && make installcheck. It cannot return a bytea as expected.
Thanks Charles! 2018-06-01 18:28 GMT-07:00 Tom Lane <t...@sss.pgh.pa.us>: > Charles Cui <charles.cui1...@gmail.com> writes: > > I have a new type defined like this > > CREATE TYPE thrift_binary ( > > INPUT = thrift_binary_in, > > OUTPUT = thrift_binary_out, > > LIKE = bytea > > ); > > > in thrift_binary_in, it accepts cstring and returns thrift_binary. > > OK, that's what it should do. > > > And in > > this function I returned a bytea because the create type tells the system > > thrift_binary and bytea are the same. > > Sure, PG_RETURN_BYTEA_P() would work in the C code. I think it might be > worth inventing a macro PG_RETURN_THRIFT_BINARY_P that's a thin wrapper > around that, just for clarity's sake, but it doesn't matter functionally. > > > However, the test passes only when I > > explicitly tell thrift_binary_in to return a bytea (change the return > type > > from thrift_binary to bytea), and it does not work when returns > > thrift_binary. > > What do you mean by "the test passes" (or doesn't pass)? What do you > mean by "tell thrift_binary_in to return a bytea"? You just said you > were already doing that. > > This works for me: > > regression=# create type thrift_binary; > CREATE TYPE > regression=# create function thrift_binary_in(cstring) returns > thrift_binary > regression-# strict immutable language internal as 'byteain'; > NOTICE: return type thrift_binary is only a shell > CREATE FUNCTION > regression=# create function thrift_binary_out(thrift_binary) returns > cstring > regression-# strict immutable language internal as 'byteaout'; > NOTICE: argument type thrift_binary is only a shell > CREATE FUNCTION > regression=# CREATE TYPE thrift_binary ( > regression(# INPUT = thrift_binary_in, > regression(# OUTPUT = thrift_binary_out, > regression(# LIKE = bytea > regression(# ); > CREATE TYPE > > I cheated here by pointing to byteain/byteaout instead of C functions > that'd actually do what you want, but CREATE TYPE doesn't know that. > > I suspect you may have forgotten the initial dummy creation of > thrift_binary as a "shell type". > > regards, tom lane >
