Hardhat allows users to configure a custom network in the networks configuration object. This allows developers to run their JS/TS test suites against another local node such as Ganache or even a live network such as an Ethereum testnet.
Can this be done in Foundry as well? For example, instead of using Foundry's default node Anvil users can specify a locally running node such as a hardhat or ganache local node that they want to run their Foundry project's test suites(written in solidity) on.
Yes, Foundry allows users to configure custom Ethereum nodes.
Custom RPC endpoints can be defined in the foundry.toml under [rpc_endpoints] as follows:
# foundry.toml
[rpc_endpoints]
optimism = "https://optimism.alchemyapi.io/v2/1234567" # since the foundry.toml is commited it's not recommened to have the api key explicitly
mainnet = "${RPC_MAINNET}" # it's recommened to do either this
goerli = "https://eth-goerli.alchemyapi.io/v2/${ALCHEMY_API_KEY}" # or this
forge commands typically have a flag that allows you to run various commands with specified network configurations using either an explicit RPC URL or a network alias defined in the foundry.toml
Testing with a Forked Environment:
--rpc-url, --fork-url and -f are valid options for forge test
forge test --fork-url <rpc_url_or_alias>
Deploying contracts to a network
--rpc-url is a valid option for forge create
forge create --rpc-url <rpc_url_or_alias> --private-key <your_private_key> src/MyContract.sol:MyContract
Running solidity scripts against a network
--rpc-url, --fork-url and -f are valid options for forge script
forge script --rpc-url <rpc_url_or_alias> --fork-block-number <block_number> path [args...]
yes it can be done, if you spin your local hardhat node, you can then run your tests like:
forge test --fork-url http://127.0.0.1:8545 -vv --match-test testYOURTEST
where http://127.0.0.1:8545` refers to your hardhat node. Or in case you want to fork ethereum mainnet, then your mainnet RPC
Hope it helps
