In order to ensure that the change of nVersion to a uint32_t in the
previous commit has no effect, rename nVersion to version in this commit
so that reviewers can easily spot if a spot was missed or if there is a
check somewhere whose semantics have changed.
Adds test in mempool_accept to check if a negative maxfeerate is inputed
into check_mempool_result, asserts "Amount out of range" error message
and -3 error code
In functional tests it is a quite common scenario to generate fresh
elliptic curve keypairs, which is currently a bit cumbersome as it
involves multiple steps, e.g.:
privkey = ECKey()
privkey.generate()
privkey_wif = bytes_to_wif(privkey.get_bytes())
pubkey = privkey.get_pubkey().get_bytes()
Simplify this by providing a new `generate_keypair` helper function that
returns the private key either as `ECKey` object or as WIF-string
(depending on the boolean `wif` parameter) and the public key as
byte-string; these formats are what we mostly need (currently we don't
use `ECPubKey` objects from generated keypairs anywhere).
With this, most of the affected code blocks following the pattern above
can be replaced by one-liners, e.g.:
privkey, pubkey = generate_keypair(wif=True)
Note that after this commit, the only direct uses of `ECKey` remain in
situations where we want to set the private key explicitly, e.g. in
MiniWallet (test/functional/test_framework/wallet.py) or the test for
the signet miner script (test/functional/tool_signet_miner.py).
Since the original fix was set to be a "reasonable" transaction
to reduce allocations and the true motivation later revealed,
it makes sense to relax this check to something more principled.
There are more exotic transaction patterns that could take advantage
of a relaxed requirement, such as 1 input, 1 output OP_RETURN to burn
a utxo to fees for CPFP purposes when change isn't practical.
Two changes could be accomplished:
1) Anything not 64 bytes could be allowed
2) Anything above 64 bytes could be allowed
In the Great Consensus Cleanup, suggestion (2) was the route taken.
It would not allow an "empty" OP_RETURN
but would reduce the required padding from 22 bytes to 5.
The functional test is also modified to test the actual case
we care about: 64 bytes
We were throwing two different errors for the same problematic:
* "Expected type {expected], got {type}" --> RPCTypeCheckArgument()
* "JSON value of type {type} is not of expected type {expected}" --> UniValue::checkType()
