Setup Your Project with Foundry

This tutorial will show you how to install and use Analog GMP contracts with Foundry.

Getting Started

Ensure you’ve installed Foundry .
To start a new project with Foundry, use forge init:


forge init hello_gmp

This creates a new directory called “hello_gmp” from the default Foundry template and initializes a new GIT repository.

You may have to add your remappings in remappings.txt by running this command:


forge remappings > remappings.txt

Your project should now be correctly set up to work with Analog GMP contracts. From now on, simply import the Analog GMP dependencies into your contract from @analog-gmp as follows:


import {IGmpReceiver} from "@analog-gmp/interfaces/IGmpReceiver.sol";
import {IGateway} from "@analog-gmp/interfaces/IGateway.sol";

For example, create a sample contract in the src directory, such as counter.sol, using the following code:


// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
 
import {IGmpReceiver} from "@analog-gmp/interfaces/IGmpReceiver.sol";
 
contract Counter is IGmpReceiver {
    address private immutable _gateway;
    uint256 public number;
 
    constructor(address gateway) {
        _gateway = gateway;
    }
 
    function onGmpReceived(bytes32, uint128, bytes32, bytes calldata) external payable returns (bytes32) {
        require(msg.sender == _gateway, "unauthorized");
        number++;
        return bytes32(number);
    }
}

Now run:


forge build

This should display a successful compilation message, as shown here:


[⠊] Compiling...
[⠊] Compiling 28 files with Solc 0.8.13
[⠒] Solc 0.8.13 finished in 949.34ms
Compiler run successful!
--> src/Counter.sol

Writing Tests

You can easily write cross-chain unit tests using Analog testing tools at @analog-gmp-testing.


import {GmpTestTools} from "@analog-gmp-testing/GmpTestTools.sol";
 
// Deploy gateway contracts and create forks for all supported networks
GmpTestTools.setup();
 
// Set `account` balance in all networks
GmpTestTools.deal(address(account), 100 ether);
 
// Switch to Sepolia network
GmpTestTools.switchNetwork(5);
 
// Switch to Shibuya network and set `account` as `msg.sender` and `tx.origin`
GmpTestTools.switchNetwork(7, address(account));
 
// Relay all pending GMP messages.
GmpTestTools.relayMessages();

Build


forge build

Test


forge test

This should display a successful test message, as shown here:


[⠊] Compiling...
No files changed, compilation skipped
 
Ran 2 tests for test/Counter.t.sol:CounterTest
[PASS] testFuzz_SetNumber(uint256) (runs: 256, μ: 30977, ~: 31288)
[PASS] test_Increment() (gas: 31303)
Suite result: ok. 2 passed; 0 failed; 0 skipped; finished in 19.97ms (9.69ms CPU time)
 
Ran 1 test suite in 145.98ms (19.97ms CPU time): 2 tests passed, 0 failed, 0 skipped (2 total tests)