I assume it rejects the transaction because I am trying to spend an input that is not yet confirmed. However, what if I want to spend that input on a CPFP transaction to broadcast the original transaction faster?
It should return "
true" even if the input(s) isn't included in a block.
It's probably because the the parent is not currently "
not in memory pool", using
sendrawtransaction to the parent before attempting to use
testmempoolaccept to the child should work.