feat(sdk-coin-stx): added check for multiple reciepents

TICKET: COIN-1959

Author: mohd-kashif

modules/sdk-coin-stx/src/stx.ts

@@ -46,7 +46,10 @@ export class Stx extends BaseCoin {
   }
 
   async verifyTransaction(params: VerifyTransactionOptions): Promise<boolean> {
-    // TODO: Implement when available on the SDK.
+    const { txParams } = params;
+    if (txParams?.recipients?.length !== 1) {
+      throw new Error(`txParams should only have 1 recipient but ${txParams?.recipients?.length} found`);
+    }
     return true;
   }
 

modules/sdk-coin-stx/test/unit/stx.ts

@@ -4,6 +4,7 @@ import { coins } from '@bitgo/statics';
 import * as testData from '../fixtures';
 import { Stx, Tstx, StxLib } from '../../src';
 import assert from 'assert';
+import { Wallet } from '@bitgo/sdk-core';
 
 const { KeyPair } = StxLib;
 
@@ -284,4 +285,25 @@ describe('STX:', function () {
       bufferTx.should.be.deepEqual(Buffer.from(testData.unsignedTxForExplainTransfer));
     });
   });
+
+  describe('Verify Transaction', function () {
+    const address1 = '0x174cfd823af8ce27ed0afee3fcf3c3ba259116be';
+    const address2 = '0x7e85bdc27c050e3905ebf4b8e634d9ad6edd0de6';
+    it('should reject a txPrebuild with more than one recipient', async function () {
+      const wallet = new Wallet(bitgo, basecoin, {});
+
+      const txParams = {
+        recipients: [
+          { amount: '1000000000000', address: address1 },
+          { amount: '2500000000000', address: address2 },
+        ],
+        wallet: wallet,
+        walletPassphrase: 'fakeWalletPassphrase',
+      };
+
+      await basecoin
+        .verifyTransaction({ txParams })
+        .should.be.rejectedWith('txParams should only have 1 recipient but 2 found');
+    });
+  });
 });