hardhat.config.ts

import { HardhatUserConfig } from "hardhat/config";
import "@nomiclabs/hardhat-waffle";
import "@nomicfoundation/hardhat-verify";
import * as dotenv from "dotenv";

dotenv.config();

// Normalize the deployer key (hardhat wants a 0x-prefixed hex private key).
const rawKey = process.env.PRIVATE_KEY_TESTNET || "";
const testnetKey = rawKey ? [rawKey.startsWith("0x") ? rawKey : `0x${rawKey}`] : [];
const bscTestnetRpc =
  process.env.BSC_TESTNET_RPC_URL || "https://bsc-testnet-dataseed.bnbchain.org";

/**
 * Uniswap V2 uses two Solidity versions:
 *   - core      -> 0.5.16
 *   - periphery -> 0.6.6
 * Shared interfaces (pragma >=0.5.0 / >=0.6.2) are compiled under whichever
 * version the importing contract requires. Optimizer settings and EVM target
 * mirror the original Uniswap build (999999 runs, istanbul) so the compiled
 * bytecode — and therefore gas snapshots and CREATE2 addresses — match.
 */
const optimizer = { enabled: true, runs: 999999 };

const config: HardhatUserConfig = {
  solidity: {
    compilers: [
      { version: "0.5.16", settings: { optimizer, evmVersion: "istanbul" } },
      { version: "0.6.6", settings: { optimizer, evmVersion: "istanbul" } },
    ],
  },
  networks: {
    hardhat: {
      // Uniswap V2 tests were written against a chainId of 1 (used in the
      // EIP-712 domain separator for permit); keep it so digests match.
      chainId: 1,
      hardfork: "istanbul",
      allowUnlimitedContractSize: true,
      // Start the chain before 2020 so the sliding-window oracle spec can set
      // its absolute start timestamp (1577836800 = 2020-01-01) going forward.
      initialDate: "2019-01-01T00:00:00Z",
      // The Uniswap oracle specs were written against ganache, where consecutive
      // txs in the same real second share a block timestamp. Allow that here so
      // setup txs don't drift past the anchored start time.
      allowBlocksWithSameTimestamp: true,
    },
    bscTestnet: {
      url: bscTestnetRpc,
      chainId: 97,
      accounts: testnetKey,
    },
  },
  etherscan: {
    // Etherscan V2 unified API — a single key routes to BSC by chainId.
    apiKey: process.env.ETHERSCAN_API_KEY || process.env.BSCSCAN_API_KEY || "",
  },
  paths: {
    sources: "./contracts",
    tests: "./test",
  },
  mocha: {
    timeout: 200000,
  },
};

export default config;