fix: ensure bestDescendant when bestChild set in applyDeltas#549
Merged
ch4r10t33r merged 5 commits intomainfrom Feb 6, 2026
Merged
fix: ensure bestDescendant when bestChild set in applyDeltas#549ch4r10t33r merged 5 commits intomainfrom
ch4r10t33r merged 5 commits intomainfrom
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…n applyDeltas Fixes panic 'invalid forkchoice with null best descendant for a non null best child' during rebase (issue #545). Add regression test with cutoff_weight.
ch4r10t33r
changed the title
anshalshukla
reviewed
Feb 6, 2026
anshalshukla
previously approved these changes
Feb 6, 2026
If bestDescendant is null (e.g., when cutoff_weight filters out descendants), keep it null after rebase rather than remapping to bestChild. Addresses review comment from @g11tech.
g11tech
approved these changes
Feb 6, 2026
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Fixes panic
invalid forkchoice with null best descendant for a non null best childduring rebase (issue #545).applyDeltas, when a parent's best child had weight belowcutoff_weightand no descendant above cutoff,bestDescendantwas set tonullwhilebestChildwas set, violating the invariant expected byrebase().bestDescendant = nodeBestDescendant orelse node_idxso the invariant (bestChild non-null ⇒ bestDescendant non-null) always holds.rebase: bestChild/bestDescendant invariant maintained with cutoff_weightthat applies deltas withcutoff_weight > 0and then rebases (previously panicked).