Foundry tests for LayerZero contracts using a mock Endpoint

LayerZero is an omnichain omnichain interoperability protocol. The protocol consists of a crucial off-chain component, called a relayer. This piece of technology is responsible for transferring messages across chains.

This however makes it difficult to test smart contracts on a local blockchain instance like Anvil, Hardhat node, Ganache.

The LayerZero team however provides a mock endpoint that can be used to simulate cross-chain communication using a single blockchain.

This repo was built as an exercise in learning to figure out how to use the mock endpoint to write tests in Foundry.

Overview

The OmniCounter project consists of:

• OmniCounter_Sepolia.sol: A contract deployed on the Sepolia testnet.
• OmniCounter_Mumbai.sol: A contract deployed on the Mumbai testnet.
• OmniCounter.t.sol: A test contract to ensure the functionality and interoperability of the above contracts.

The main functionality revolves around incrementing a counter on one chain and observing the corresponding increment on the other chain, showcasing real-time cross-chain communication.

How to use

Note that you will need to have Foundry installed in your system. Refer to Foundry book for relevent instructions.

To use, Simply, clone the repo, and then:

1. To compile the contracts:

forge build

2. To run the tests:

forge test --match-path test/OmniCounter.t.sol -vvvv

The verbosity flag(-v) is set to maximum to output the stack trace for all the calls happening in the test functions. Helpful for debugging.