- This commit renamed coinbase_max_additional_weight to block_reserved_weight.
- Also clarify that the reservation is for block header, transaction count
and coinbase transaction.
In python, if the default value is a mutable object (here: a class)
its shared over all instances, so that one instance being changed
would affect others to be changed as well.
This was likely the source of various intermittent bugs in the
functional tests.
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.
55556a64a8 test: Remove struct import from messages.py (MarcoFalke)
fa3fa86dda scripted-diff: test: Use int from_bytes and to_bytes over struct packing (MarcoFalke)
fafc0d68ee test: Use int from_bytes and to_bytes over struct packing (MarcoFalke)
fa3886b7c6 test: Treat msg_version.relay as unsigned (MarcoFalke)
Pull request description:
`struct` has many issues in messages.py:
* For unpacking, it requires to specify the length a second time, even when it is already clear from the `f.read(num_bytes)` context.
* For unpacking, it is designed to support a long format string and returning a tuple of many values. However, except for 3 instances in `messages.py`, usually only a single value is unpacked and all those cases require an `[0]` access.
* For packing and unpacking of a single value, the format string consists of characters that may be confusing and may need to be looked up in the documentation, as opposed to using easy to understand self-documenting code.
I presume the above issues lead to accidentally treat `msg_version.relay` as a "signed bool", which is fine, but confusing.
Fix all issues by using the built-in `int` helpers `to_bytes` and `from_bytes` via a scripted diff.
Review notes:
* `struct.unpack` throws an error if the number of bytes passed is incorrect. `int.from_bytes` doesn't know about "missing" bytes and treats an empty byte array as `int(0)`. "Extraneous" bytes should never happen, because all `read` calls are limited in this file. If it is important to keep this error behavior, a helper `int_from_stream(stream, num_bytes, bytes, byteorder, *, **kwargs)` can be added, which checks the number of bytes read from the stream.
* For `struct.pack` and `int.to_bytes` the error behavior is the same, although the error messages are not identical.
ACKs for top commit:
stickies-v:
ACK 55556a64a8
theStack:
re-ACK 55556a64a8
Tree-SHA512: 1cef8cdfd763fb424ed4b8be850a834b83fd0ef47fbea626a29784eb4f4832d44e42c4fe05b298b6070a933ef278b0222289a9955a97c86707e091e20bbb247a
The C++ code treats bool as uint8_t, so the python tests should as well.
This also allows to simplify the code, because converting an empty byte
array to int gives int(0).
>>> int.from_bytes(b'')
0
This avoids circular dependency happening when importing MAGIC_BYTES.
Before,
p2p.py <--import for EncryptedP2PState-- v2_p2p.py
| ^
| |
└---------import for MAGIC_BYTES----------┘
Now, MAGIC_BYTES are kept separately in messages.py
Co-authored-by: Martin Zumsande <mzumsande@gmail.com>
These routines look fancy, but do nothing more than converting between
byte objects of length 32 to/from integers in little endian byte order
and can be replaced by simple one-liners, using the int.{from,to}_bytes
methods (available since Python 3.2).
