chore(utxo-coredao): add fixture from testnet3

Be able to provide pubkey buffers as well

TICKET: BTC-1578

Author: davidkaplanbitgo

modules/utxo-coredao/src/descriptor.ts

@@ -5,19 +5,27 @@ import { BIP32Interface } from '@bitgo/utxo-lib';
  */
 export type ScriptType = 'sh' | 'sh-wsh';
 
+function asDescriptorKey(key: BIP32Interface | Buffer, neutered: boolean): string {
+  if (Buffer.isBuffer(key)) {
+    return key.toString('hex');
+  }
+  return (neutered ? key.neutered() : key).toBase58() + '/*';
+}
+
 /**
  * Create a multi-sig descriptor to produce a coredao staking address
  * @param scriptType segwit or legacy
  * @param locktime locktime for CLTV
  * @param m Total number of keys required to unlock
- * @param orderedKeys
+ * @param orderedKeys If Bip32Interfaces, these are xprvs or xpubs and are derivable.
+ *                    If they are buffers, then they are pub/prv keys and are not derivable.
  * @param neutered If true, neuter the keys. Default to true
  */
 export function createMultiSigDescriptor(
   scriptType: ScriptType,
   locktime: number,
   m: number,
-  orderedKeys: BIP32Interface[],
+  orderedKeys: (BIP32Interface | Buffer)[],
   neutered = true
 ): string {
   if (m > orderedKeys.length || m < 1) {
@@ -28,8 +36,7 @@ export function createMultiSigDescriptor(
   if (locktime <= 0) {
     throw new Error(`locktime (${locktime}) must be greater than 0`);
   }
-
-  const xpubs = orderedKeys.map((key) => (neutered ? key.neutered() : key).toBase58() + '/*');
-  const inner = `and_v(r:after(${locktime}),multi(${m},${xpubs.join(',')}))`;
+  const keys = orderedKeys.map((key) => asDescriptorKey(key, neutered));
+  const inner = `and_v(r:after(${locktime}),multi(${m},${keys.join(',')}))`;
   return scriptType === 'sh' ? `sh(${inner})` : `sh(wsh(${inner}))`;
 }

modules/utxo-coredao/src/index.ts

@@ -1 +1,2 @@
 export * from './opReturn';
+export * from './descriptor';

modules/utxo-coredao/test/unit/descriptor.ts

@@ -4,6 +4,7 @@ import { Descriptor } from '@bitgo/wasm-miniscript';
 
 import { createMultiSigDescriptor } from '../../src/descriptor';
 import { finalizePsbt, getFixture, updateInputWithDescriptor } from './utils';
+import { decodeTimelock } from '../../src';
 
 describe('descriptor', function () {
   const baseFixturePath = 'test/fixtures/descriptor/';
@@ -114,4 +115,36 @@ describe('descriptor', function () {
   runTestForParams('sh', 2, [key1, key2]);
   runTestForParams('sh-wsh', 2, [key1, key2]);
   runTestForParams('sh', 3, [key1, key2, key3]);
+
+  it('should recreate the script used in testnet staking transaction', function () {
+    // Source: https://mempool.space/testnet/address/2MxTi2EhHKgdJFKRTBttVGGxir9ZzjmKCXw
+    // 2 of 2 multisig
+    const timelock = 'fce4cb66';
+    const pubkey1 = '03ecb6d4b7f5d56962e547fc52dd588359f5729c0ba856d6978b84723895a16691';
+    const pubkey2 = '024aaea25d82b1db2be030a05b641d6302e48ed652b1ca9cb08a67267fcbb56747';
+    const redeemScriptASM = [
+      'OP_PUSHBYTES_4',
+      timelock,
+      'OP_CLTV',
+      'OP_DROP',
+      'OP_PUSHNUM_2',
+      'OP_PUSHBYTES_33',
+      pubkey1,
+      'OP_PUSHBYTES_33',
+      pubkey2,
+      'OP_PUSHNUM_2',
+      'OP_CHECKMULTISIG',
+    ].join(' ');
+
+    const decodedTimelock = decodeTimelock(Buffer.from(timelock, 'hex'));
+    const descriptor = createMultiSigDescriptor(
+      'sh',
+      decodedTimelock,
+      2,
+      [Buffer.from(pubkey1, 'hex'), Buffer.from(pubkey2, 'hex')],
+      false
+    );
+    const descriptorASM = Descriptor.fromString(descriptor, 'definite').toAsmString();
+    assert.deepStrictEqual(redeemScriptASM, descriptorASM);
+  });
 });