Add test for transfercoin fail if balance undifined

assembly/__tests__/env-coins.spec.ts

@@ -1,7 +1,11 @@
 // This file is aim to test the env coins related functions which are external functions
 
 import { env } from '../env';
-import { resetStorage, mockTransferredCoins } from '../vm-mock';
+import {
+  resetStorage,
+  mockTransferredCoins,
+  addAddressToLedger,
+} from '../vm-mock';
 import { Address } from '../std';
 
 const testAddress = new Address(
@@ -12,6 +16,10 @@ const testAddress2 = new Address(
   'AU12E6N5BFAdC2wyiBV6VJjqkWhpz1kLVp2XpbRdSnL1mKjCWT6oT',
 );
 
+const testAddress3 = new Address(
+  'AU12E6N5BFAdC2wyiBV6VJjqkWhpz1kLVp2XpbRdSnL1mKjCWT6oU',
+);
+
 beforeEach(() => {
   // We set the balance of the current contract to 100000 in the resetStorage
   resetStorage();
@@ -52,6 +60,18 @@ describe('Testing env coins related functions', () => {
     expect(env.balanceOf(testAddress2.toString())).toBe(amount);
   });
 
+  it('transferCoins to mock address created with addAddressToLedger', () => {
+    addAddressToLedger(testAddress3.toString());
+    const amount: u64 = 100;
+    const receiverCurrentBalance = env.balanceOf(testAddress3.toString());
+    // given
+    expect(receiverCurrentBalance).toBe(0);
+    // when
+    env.transferCoins(testAddress3.toString(), amount);
+    // then
+    expect(env.balanceOf(testAddress3.toString())).toBe(amount);
+  });
+
   it('get the balance of an address', () => {
     const amount: u64 = 100;
     // given