evm: added bundler3 multicall helper function

Author: kev1n-peters

platforms/evm/src/bundler3.ts

@@ -0,0 +1,73 @@
+import {
+  MapLevel,
+  Chain,
+  constMap,
+  Network,
+} from '@wormhole-foundation/sdk-connect';
+import { Contract, TransactionRequest, ZeroHash } from 'ethers';
+
+const bundler3Contracts = [
+  ['Mainnet', [['Polygon', '0x2d9C3A9E67c966C711208cc78b34fB9E9f8db589']]],
+] as const satisfies MapLevel<Network, MapLevel<Chain, string>>;
+
+export const bundler3Contract = constMap(bundler3Contracts);
+
+export interface Call {
+  to: string;
+  data: string;
+  value: bigint;
+  skipRevert: boolean;
+  callbackHash: string; // bytes32
+}
+
+/**
+ * Populates a transaction request with a multicall to the bundler3 contract
+ * @param calls - Array of calls to be made in the multicall
+ * @param bundler3Address - Address of the bundler3 contract
+ * @returns Promise<TransactionRequest>
+ *
+ * See: https://docs.morpho.org/bundlers/tutorials/bundler3-solidity
+ */
+export async function populateMulticallTx(
+  calls: Call[],
+  bundler3Address: string,
+): Promise<TransactionRequest> {
+  if (calls.length === 0) {
+    throw new Error('No transactions provided');
+  }
+
+  if (!bundler3Address) {
+    throw new Error('bundler3 address required');
+  }
+
+  const bundler3 = new Contract(bundler3Address, [
+    'function multicall((address to, bytes data, uint256 value, bool skipRevert, bytes32 callbackHash)[]) external payable',
+  ]);
+
+  const tx = await bundler3.getFunction('multicall').populateTransaction(calls);
+
+  tx.value = calls.reduce((acc, tx) => acc + tx.value, 0n);
+
+  return tx;
+}
+
+export function txReqToCall(
+  tx: TransactionRequest,
+  skipRevert = false,
+  callbackHash = ZeroHash,
+): Call {
+  if (!tx.to) throw new Error('Invalid transaction: to required');
+
+  if (typeof tx.to !== 'string')
+    throw new Error('Invalid transaction: to must be a string');
+
+  if (!tx.data) throw new Error('Invalid transaction: data required');
+
+  return {
+    to: tx.to,
+    data: tx.data,
+    value: BigInt(tx.value ?? 0n),
+    skipRevert,
+    callbackHash,
+  };
+}

platforms/evm/src/index.ts

@@ -4,3 +4,5 @@ export * from './platform.js';
 export * from './types.js';
 export * from './chain.js';
 export * from './signer.js';
+
+export * as bundler3 from './bundler3.js';