feat: ENSO Checkout Simulator v0.0.1

[vnavascues]

How To

1. Install requirements and dependencies:

$ foundryup
$ pnpm install
$ pnpm foundry:update

2. Set up Anvil fork env vars in .env (defaults below):

ANVIL_PORT=8545
FORK_URL=https://ethereum-rpc.publicnode.com
FORK_BLOCK_NUMBER=-1 # 'latest' is not supported, -1 will useto the latest - 1.
FORK_CHAIN_ID=1

3. Set up Simulator server (Fastify) env vars in .env (defaults below):

SIM_ENSO_CHECKOUT_PORT=3000

4. Spin up Anvil & Simulator server (the script below should source the .env):

$ simulator:enso_checkout:start:with_anvil

Or enabling Fastify hot reload (but not Anvil):

$ simulator:enso_checkout:start:dev:with_anvil

5. Integrator (e.g., Backend) must POST /simulate with a SimulationRequest payload:

NOTE: current commit is mocking SimulationRequest not only for testing purposes but also until we decide how to format handleOpsCalldata and/or handleOps. That choice will determine how we'll execute EntryPoint.handlOps(PackedUserOperation[] memory, address) (e.g., external call, low-level call).

export interface ForgeData {
  profile?: string;
  contract?: string;
  test?: string;
  testRelativePath?: string;
  rpcUrl?: string;
  logFormat?: ForgeTestLogFormat;
  logVerbosity?: ForgeTestLogVerbosity;
  isTxDataLogged?: boolean;
  isTestResultsLogged?: boolean;
}

export interface ShortcutData {
  tokensInFundingRequired: boolean[];
  tokensInTypes: TokenType[];
  tokensIn: AddressArg[];
  amountsIn: string[]; // BigNumberish
  tokensInHolders: AddressArg[];
}

export interface PackedUserOperation {
  sender: AddressArg;
  nonce: HexString;
  initCode: HexString;
  callData: HexString;
  accountGasLimits: HexString;
  preVerificationGas: string; // BigNumberish
  gasFees: HexString;
  paymasterAndData: HexString;
  signature: HexString;
}

export interface HandleOps {
  ops: PackedUserOperation[];
  beneficiary: AddressArg;
}

export interface SimulationRequest {
  [key: string]: any;
  forgeData?: ForgeData;
  shortcutData: ShortcutData;
  backendSigner: AddressArg;
  ensoReceiver: AddressArg; // NOTE: counterfactual
  signaturePaymaster: AddressArg;
  bundler: AddressArg;
  entryPoint: AddressArg;
  // handleOps?: HandleOps; // NOTE: disabled
  handleOpsCalldata: HexString;
}