Homestead: reduce redundant int() casts in calculate_block_difficulty (#1415) #1460
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
SamWilsn
reviewed
Oct 10, 2025
| can't be less difficult than the genesis block, therefore each block's | ||
| difficulty is set to the maximum value between the calculated | ||
| difficulty and the ``GENESIS_DIFFICULTY``. | ||
| """Homestead difficulty: same behavior, fewer int() casts.""" |
There was a problem hiding this comment.
Should probably keep the docstring.
Comment on lines
+745
to
+746
| pd_int = int(parent_difficulty) | ||
| dt_int = int(block_timestamp) - int(parent_timestamp) |
There was a problem hiding this comment.
We try to avoid opaque variable names, and instead prefer full words whenever possible.
Comment on lines
-786
to
-790
| # Historical Note: The difficulty bomb was not present in Ethereum at the | ||
| # start of Frontier, but was added shortly after launch. However since the | ||
| # bomb has no effect prior to block 200000 we pretend it existed from | ||
| # genesis. | ||
| # See https://github.com/ethereum/go-ethereum/pull/1588 |
There was a problem hiding this comment.
Please keep the comments.
| num_bomb_periods = (int(block_number) // 100000) - 2 | ||
| if num_bomb_periods >= 0: | ||
| difficulty += 2**num_bomb_periods | ||
| diff_int += 1 << num_bomb_periods |
There was a problem hiding this comment.
Why change this to a shift?
| parent_difficulty : | ||
| difficulty of the parent block. | ||
| # Base adjustment and signed offset (can be negative). | ||
| base = pd_int // 2048 |
There was a problem hiding this comment.
I don't think base can be negative at this point?
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Description
Refactors
calculate_block_difficultyin the Homestead fork to avoid repeatedint()casts while keeping behavior identical.intfor the (signed) offset math.MINIMUM_DIFFICULTY.Uint.No behavioral change intended; this is a readability/micro-perf cleanup.
Related issue
Refs #1415.
Rationale
Test plan
codespell: ✅ruff check+ruff format --check: ✅mypy: ✅ethereum-spec-lintshows aGlacierForksHygienemessage locally even with only Homestead touched; opening as Draft to confirm CI behavior and get guidance.tox -e py3 -- -k 'homestead and difficulty'✅tox -e py3→ 61013 passed, 473 skipped on my box ✅Notes
Per maintainer advice, this PR limits changes to Homestead. I’m happy to follow up with the remaining forks after review feedback on this pattern.
@SamWilsn , Homestead-only refactor for #1415. Static is green locally; full tox -e py3 also green. Open as Draft for feedback.