Remove Smt class lock

[martti007]

No description provided.

[gemini-code-assist]

Summary of Changes

Hello @martti007, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request refactors the Smt class by removing its internal concurrency control mechanism and simplifying its API. The primary change involves making the rootHash and getPath operations asynchronous, as they now compute the Merkle tree root on demand, rather than maintaining a cached state. This change propagates throughout the codebase, updating all instances where the Smt class is used.

Highlights

• Smt Class Simplification: The internal locking mechanism (smtUpdateLock, waitingPromises, LOCK_TIMEOUT_MS, acquireSmtLock, releaseSmtLock, withSmtLock) within the Smt class has been completely removed. This simplifies the class by delegating concurrency concerns, if any, to the underlying SparseMerkleTree or higher-level application logic.
• Asynchronous SMT Root Calculation: The rootHash and getPath methods of the Smt class are now asynchronous. They no longer rely on a cached _root property but instead calculate the Sparse Merkle Tree root on demand by calling await this.smt.calculateRoot().
• Smt Instantiation Changes: The static asynchronous Smt.create factory method has been removed. The Smt class can now be instantiated synchronously using new Smt(smt), reflecting the removal of the initial root calculation from the constructor/factory.
• Codebase Adaptation: All call sites across the application, including AggregatorGateway, RoundManager, AggregatorRouter, and various test files, have been updated to reflect the changes in the Smt class. This primarily involves changing Smt.create calls to new Smt() and accessing rootHash and getPath as await smt.rootHash() or await smt.getPath().

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[Copilot]

Pull Request Overview

This PR removes the locking mechanism from the Smt class wrapper around SparseMerkleTree. The changes eliminate the concurrency control that was previously implemented to ensure sequential execution of asynchronous operations on the SMT.

Key changes:

• Removed the internal locking mechanism (smtUpdateLock, waitingPromises, timeout handling)
• Changed rootHash from a synchronous property to an asynchronous method
• Simplified the constructor by removing the static create method
• Updated all callers to use the new constructor and async rootHash() method

Reviewed Changes

Copilot reviewed 10 out of 10 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
src/smt/Smt.ts	Removed locking mechanism, converted rootHash to async method, simplified constructor
tests/smt/SmtTest.ts	Completely removed test file that was testing the locking functionality
src/RoundManager.ts	Updated to use async rootHash() method
src/router/AggregatorRouter.ts	Updated to use async rootHash() method with proper error handling
src/AggregatorGateway.ts	Updated constructor usage and async rootHash() calls
tests/smt/SmtChunkedLoadingTest.ts	Updated to use async rootHash() method
tests/benchmarks/BlockCreationBenchmarkTest.ts	Updated constructor usage and removed extra blank line
tests/RoundManagerUnitTest.ts	Updated constructor usage and reordered imports
tests/AggregatorServiceTest.ts	Updated constructor usage

[gemini-code-assist]

Code Review

This pull request refactors the Smt class to remove its internal locking mechanism. This simplifies the class significantly, but it also introduces a critical race condition, as concurrent updates to the SMT are no longer serialized. This could lead to data corruption. Additionally, there's a performance regression, as the SMT root is now recalculated on every read access instead of being cached. My review includes detailed comments on these two issues with suggestions for how to address them.