Bottom up creation of required union with empty table fails #4
Description
Hi,
I have a project with a schema for messages where a union is used to include the contents of the message.
namespace UnionWithEmpty;
table RequestSomething {}
table Something { thing:uint; }
union MessageContents {RequestSomething, Something}
table Message {
to:[uint] (required);
from:uint;
contents:MessageContents (required);
}
root_type Message;
However, when I try to create a RequestSomething message bottom up, I get a required assert. If i add a dummy field to RequestSomething, the example starts to work:
#include <stdio.h>
#include <assert.h>
#include "union_with_empty_builder.h"
#define ns(x) FLATBUFFERS_WRAP_NAMESPACE(UnionWithEmpty, x)
#define ARRAYSIZE(x) (sizeof(x)/sizeof(x[0]))
static size_t create_works(uint8_t *buf)
{
flatcc_builder_t builder;
flatcc_builder_t *B = &builder;
flatcc_builder_init(B);
ns(Message_start_as_root(B));
uint32_t to[] = {1,2,3};
uint32_t from = 5;
ns(Message_to_create(B, to, ARRAYSIZE(to)));
ns(Message_from_add(B, from));
ns(RequestSomething_ref_t) req = ns(RequestSomething_create(B));
ns(Message_contents_add(B, ns(MessageContents_as_RequestSomething(req))));
ns(Message_end_as_root(B));
size_t size = flatcc_builder_get_buffer_size(B);
flatcc_builder_copy_buffer(B, buf, size);
flatcc_builder_clear(B);
return size;
}
static size_t create_fails(uint8_t *buf)
{
flatcc_builder_t builder;
flatcc_builder_t *B = &builder;
flatcc_builder_init(B);
ns(RequestSomething_ref_t) req = ns(RequestSomething_create(B));
ns(Message_start_as_root(B));
uint32_t to[] = {1,2,3};
uint32_t from = 5;
ns(Message_to_create(B, to, ARRAYSIZE(to)));
ns(Message_from_add(B, from));
ns(Message_contents_add(B, ns(MessageContents_as_RequestSomething(req))));
ns(Message_end_as_root(B));
size_t size = flatcc_builder_get_buffer_size(B);
flatcc_builder_copy_buffer(B, buf, size);
flatcc_builder_clear(B);
return size;
}
static void decode(const uint8_t *buf)
{
ns(Message_table_t) dec = ns(Message_as_root(buf));
printf("type = '%s'\n", ns(MessageContents_type_name(ns(Message_contents_type(dec)))));
}
int main()
{
uint8_t buf[1024];
create_works(buf);
create_fails(buf);
decode(buf);
return 0;
}Thank you for making flatcc!