b82f7843ff
## Issue Addressed While reviewing #4801 I noticed that our use of `take_while` in the block replayer means that if a state root iterator _with gaps_ is provided, some additonal state roots will be dropped unnecessarily. In practice the impact is small, because once there's _one_ state root miss, the whole tree hash cache needs to be built anyway, and subsequent misses are less costly. However this was still a little inefficient, so I figured it's better to fix it. ## Proposed Changes Use [`peeking_take_while`](https://docs.rs/itertools/latest/itertools/trait.Itertools.html#method.peeking_take_while) to avoid consuming the next element when checking whether it satisfies the slot predicate. ## Additional Info There's a gist here that shows the basic dynamics in isolation: https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=40b623cc0febf9ed51705d476ab140c5. Changing the `peeking_take_while` to a `take_while` causes the assert to fail. Similarly I've added a new test `block_replayer_peeking_state_roots` which fails if the same change is applied inside `get_state_root`. |
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| .. | ||
| common | ||
| per_block_processing | ||
| per_epoch_processing | ||
| upgrade | ||
| block_replayer.rs | ||
| consensus_context.rs | ||
| genesis.rs | ||
| lib.rs | ||
| macros.rs | ||
| metrics.rs | ||
| per_block_processing.rs | ||
| per_epoch_processing.rs | ||
| per_slot_processing.rs | ||
| state_advance.rs | ||
| upgrade.rs | ||
| verify_operation.rs | ||