The Optimism utilities is a small package to provide some additional utilities required for those that wish to more closely interact with Optimism-sepcific features.

This package is currently experimental and beta; the API is subject to change.

/home/ricmoo> npm install @ethers-ext/utils-optimism

By default, estimateGas will connect to the Ethers default Optimism provider. When providing a transaction, using a fully populated transaction will result in the best possible L1 estimation.

import { estimateGas } from "@ethers-ext/utils-optimism";
// Given a transaction
// const tx = wallet.populateTransaction(...txParams);
// ... or ...
// const tx = contract.foobar.populateTransaction(...args);
const { gas, gasL1, gasL2 } = await estimateGas(tx);

An optional second parameter may be passed into choose another Provider:

// Connect to the default Optimism Goerli provider
result = await estimateGas(tx, "optimism-goerli")
// Connect to a local JSON-RPC provider
result = await estimateGas(tx, "https://localhost:8545")
// Connect to a normal Ethers provider, like MetaMask
provider = new BrowserProvider(window.ethereum)
result = await estimateGas(tx, provider)

Estimate the L1 and L2 gas requirements for tx. If provider is not specified the default Ethers provider for Optimism is used. If a string is provided the standard getDefaultProvder logic is used.

MIT License.