The bintrie node iterator previously discarded its `start` parameter,
forcing every iteration to begin at the root. This makes resumable
generators (snapshot/flat-state population) impossible — any
interruption restarts from scratch.
Implement seek(start []byte) by walking down the trie following start's
bit path, building the iterator stack as we go. When the chosen path
dead-ends (Empty, missing child, or a stem strictly less than start),
backtrack through the existing stack to find the next in-order subtree
and descend to its leftmost leaf.
Also wire BinaryTrie.NodeIterator(startKey) to actually pass startKey
through (was hardcoded to nil).
Tests cover: empty start (no-op), exact key match, between-keys,
into empty subtree, past end, within-stem offsets, resume simulation,
and deep tree.
Fix three issues in the binary trie NodeIterator:
1. Empty nodes now properly backtrack to parent and continue iteration
instead of terminating the entire walk early.
2. `HashedNode` resolver handles `nil` data (all-zeros hash) gracefully
by treating it as Empty rather than panicking.
3. Parent update after node resolution guards against stack underflow
when resolving the root node itself.
---------
Co-authored-by: tellabg <249254436+tellabg@users.noreply.github.com>
This is broken off of #31730 to only focus on testing networks that
start with verkle at genesis.
The PR has seen a lot of work since its creation, and it now targets
creating and re-executing tests for a binary tree testnet without the
transition (so it starts at genesis). The transition tree has been moved
to its own package. It also replaces verkle with the binary tree for
this specific application.
---------
Co-authored-by: Gary Rong <garyrong0905@gmail.com>
Implement the binary tree as specified in [eip-7864](https://eips.ethereum.org/EIPS/eip-7864).
This will gradually replace verkle trees in the codebase. This is only
running the tests and will not be executed in production, but will help
me rebase some of my work, so that it doesn't bitrot as much.
---------
Signed-off-by: Guillaume Ballet
Co-authored-by: Parithosh Jayanthi <parithosh.jayanthi@ethereum.org>
Co-authored-by: rjl493456442 <garyrong0905@gmail.com>
