This merge was a bit tricky, since in Elements the witnesses are not
part of the transaction inputs themselves. This merge should be reviewed
carefully.
The subtract fee from outputs assumes that the leftover input amount
will be dropped to fees. However this only happens if that amount is
less than the cost of change. In the event that it is higher than the
cost of change, the leftover amount will actually become a change
output. To avoid this scenario, force a change type which has a high
cost of change.
Followup to commit "MOVEONLY: CWallet transaction code out of
wallet.cpp/.h" that detaches and renames some CWalletTx methods, making
into them into standalone functions or CWallet methods instead.
There are no changes in behavior and no code changes that aren't purely
mechanical. It just gives spend and receive functions more consistent
names and removes the circular dependencies added by the earlier
MOVEONLY commit.
There are also no comment or documentation changes. Removed comments
from transaction.h are just migrated to spend.h, receive.h, and
wallet.h.
Behavior might have recently changed in #17331 (it is not clear) but not
noticed because there is no test coverage.
This adds test coverage for current subtract from recipient behavior
without changing it.
Co-authored-by: Andrew Chow <achow101-github@achow101.com>
