feat(framework): disallow assign of fixedbytes of size X to bytes of size Y when X != Y

[winsvega]

🗒️ Description

fields of type fixedbytesizeN should not be assignable to bytes of size other than N

uvx --with=tox-uv tox

🔗 Related Issues

#1008

✅ Checklist

• All: Set appropriate labels for the changes.
• All: Considered squashing commits to improve commit history.
• All: Added an entry to CHANGELOG.md.
• All: Considered updating the online docs in the ./docs/ directory.
• Tests: All converted JSON/YML tests from ethereum/tests have been added to converted-ethereum-tests.txt.
• Tests: A PR with removal of converted JSON/YML tests from ethereum/tests have been opened.
• Tests: Included the type and version of evm t8n tool used to locally execute test cases: e.g., ref with commit hash or geth 1.13.1-stable-3f40e65.
• Tests: Ran mkdocs serve locally and verified the auto-generated docs for new tests in the Test Case Reference are correctly formatted.

[marioevz]

Wanted to see why tox was failing and it turns out we have this pattern in some of the tests where we convert an Address to Hash (fixed size bytes 20 to 32) in order to pass it as data in a transaction of the test:

execution-spec-tests/tests/shanghai/eip4895_withdrawals/test_withdrawals.py

Lines 208 to 213 in fff098b

	Transaction(
	sender=sender,
	gas_limit=100000,
	to=contract_address,
	data=Hash(recipient),
	)

We need to decide how to proceed with this pattern because I find it useful to convert between the two types in a test.

One possibility is to simply disallow going from bigger sizes to lower sizes, and disallow a size of zero in the bytes.

Another option is to have a special case coded in Hash to allow an Address as input.

[winsvega]

Pushed a solution, why not to be explicit about what you want to achieve:

- data=Hash(recipient),
+ data=left_pad_zeros_up_to_size(recipient, 32),