Diffing RenderedElem trees to produce VDomPatch

[Copilot]

Pull request created by AI Agent

[kilo-code-bot]

CRITICAL: Consecutive insertions after a matched element are incorrectly assigned to the same position.

The oldPtr is not incremented after processing an unmatched element (insertion). When there are multiple consecutive unmatched elements in the new array after a matched element, they all get assigned to the same insertion position.

Example: old=["a", "b"], new=["a", "x", "y", "b"]

• Expected: insert "x" at position 1, insert "y" at position 2
• Actual: both "x" and "y" inserted at position 1

Fix: Add oldPtr++ after line 330:

insertions[oldPtr] = append(insertions[oldPtr], newIdx)
oldPtr++

[kilo-code-bot]

Code Review Summary

Status: 1 Issue Found | Recommendation: Address before merge

Overview

Severity	Count
CRITICAL	1
WARNING	0
SUGGESTION	0

Issue Details (click to expand)

CRITICAL

File	Line	Issue
tsunami/rpctypes/diff.go	330	Consecutive insertions bug in computePhase1ArrayChanges - insertion positions incorrectly collapse to same index

Files Reviewed (2 files)

• tsunami/rpctypes/diff.go - 1 issue
• tsunami/rpctypes/diff_test.go - no issues

The PR implements a virtual DOM diffing algorithm for RenderedElem trees. The algorithm is well-structured with clear phase separation (phase 1 for insertions/deletions, phase 2 for updates/swaps). The bug found is a logical error in the insertion position calculation that would cause incorrect patches when multiple new elements are inserted between matched elements.

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_{Reviewed by minimax-m2.5-20260211 · 448,028 tokens}