When gob.Decode fails in LoadTransitionState, the function previously
returned nil, which triggered the fallback path that creates a fresh
TransitionState{Ended: isVerkle}. On a verkle-enabled node, this would
incorrectly mark the transition as complete, potentially causing the
node to use BinaryTrie for a partially-transitioned state.
Instead of returning nil, return a non-nil TransitionState with both
Started and Ended set to false. This ensures:
- InTransition() returns false (no partial transition in progress)
- Transitioned() returns false (transition has not completed)
- The fallback path is not triggered, preventing incorrect state
The root hash is also logged in the error message to aid debugging
corruption incidents.
This change ensures TransitionState.Copy preserves BaseRoot. During a
Verkle transition, ts.BaseRoot is required to construct the overlay MPT
when ts.InTransition() is true. Previously, copies dropped BaseRoot,
risking an invalid zero-hash base trie and inconsistent behavior.
This is the first part of #31532
It maintains a series of conversion maker which are to be updated by the
conversion code (in a follow-up PR, this is a breakdown of a larger PR
to make things easier to review). They can be used in this way:
- During the conversion, by storing the conversion markers when the
block has been processed. This is meant to be written in a function that
isn't currently present, hence [this
TODO](https://github.com/ethereum/go-ethereum/pull/31634/files#diff-89272f61e115723833d498a0acbe59fa2286e3dc7276a676a7f7816f21e248b7R384).
Part of https://github.com/ethereum/go-ethereum/issues/31583
---------
Signed-off-by: Guillaume Ballet <3272758+gballet@users.noreply.github.com>
Co-authored-by: Gary Rong <garyrong0905@gmail.com>
