Add a new invariant checker that verifies that we never charge a
fee higher than specified in the transaction; we will charge less
in some corner cases where the transacting account cannot afford
the fee.
Detect more anomalous conditions, and improve the logged error
messages.
Clarify the code flow associated with invoking the invariant checker
from `Transactor`, add extra comments and improve naming to make the
code self-documenting.
The six different ranges of TER codes are broken up into six
different enumerations. A template class allows subsets of
these enumerations to be aggregated. This technique allows
verification at compile time that no TEC codes are returned
before the signature is checked.
Conversion between TER instance and integer is provided by
named functions. This makes accidental conversion almost
impossible and makes type abuse easier to spot in the code
base.
Add coverage for a few invariant checks. Handle exception in invariant
checking code so that an check that throws an exception will still
properly return tef/tecINVARIANT_FAILED.
Add new functionality to enforce one or more sanity checks (invariants)
on transactions. Add tests for each new invariant check. Allow
for easily adding additional invariant checks in the future.
Also Resolves
-------------
- RIPD-1426
- RIPD-1427
- RIPD-1428
- RIPD-1429
- RIPD-1430
- RIPD-1431
- RIPD-1432
Release Notes
-------------
Creates a new ammendment named "EnforceInvariants" which must be
enabled in order for these new checks to run on each transaction.
