test: add mocks to unit tests

Adds mocking of Tatum library functions to create real unit tests by not calling the Tatum API and using mocks instead.

src/api/getWallet.test.ts

@@ -1,20 +1,76 @@
-import { Status } from '@tatumio/tatum';
+import { Address, AddressBalance, AddressTransaction, ResponseDto, Status } from '@tatumio/tatum';
 import { getWalletData } from './getWallet';
 
-// TODO: mock Tatum library to get real unit tests
+afterEach(() => {
+  jest.clearAllMocks();
+});
 
-test('should return error for non-existing address', async () => {
-  const result = await getWalletData('non-existing-address');
-  expect(result).toStrictEqual([Status.ERROR, null, null]);
-}, 10000);
+const WalletAddressWithTransactions = '0xb794f5ea0ba39494ce839613fffba74279579268';
+
+const createTransaction = () => {
+  return {
+    chain: '',
+    blockNumber: 1,
+    hash: '1',
+    transactionType: 'incoming' as const,
+    amount: '1',
+    timestamp: 1,
+    address: WalletAddressWithTransactions,
+  };
+};
 
 test('should return valid response for existing address', async () => {
-  const result = await getWalletData('0xb794f5ea0ba39494ce839613fffba74279579268');
+  const mockedBalanceResponse: ResponseDto<AddressBalance[]> = {
+    data: [
+      {
+        address: WalletAddressWithTransactions,
+        balance: '1',
+        type: 'native',
+      },
+    ],
+    status: Status.SUCCESS,
+  };
+
+  const mockedTransactionsResponse: ResponseDto<AddressTransaction[]> = {
+    data: new Array<AddressTransaction>(10).fill(createTransaction()).map(createTransaction),
+    status: Status.SUCCESS,
+  };
+
+  jest
+    .spyOn(Address.prototype, 'getBalance')
+    .mockReturnValueOnce(Promise.resolve(mockedBalanceResponse));
+  jest
+    .spyOn(Address.prototype, 'getTransactions')
+    .mockReturnValueOnce(Promise.resolve(mockedTransactionsResponse));
+
+  const result = await getWalletData(WalletAddressWithTransactions);
   expect(result[0]).toBe(Status.SUCCESS);
 
   expect(result[1]).toBeDefined();
   expect(result[1][0].balance.length).toBeGreaterThan(0);
 
   expect(result[2]).toBeDefined();
   expect(result[2].length).toBe(10);
-}, 10000);
+});
+
+test('should return error for non-existing address', async () => {
+  const mockedBalanceResponse: ResponseDto<AddressBalance[]> = {
+    data: null!,
+    status: Status.ERROR,
+  };
+
+  const mockedTransactionsResponse: ResponseDto<AddressTransaction[]> = {
+    data: null!,
+    status: Status.ERROR,
+  };
+
+  jest
+    .spyOn(Address.prototype, 'getBalance')
+    .mockReturnValueOnce(Promise.resolve(mockedBalanceResponse));
+  jest
+    .spyOn(Address.prototype, 'getTransactions')
+    .mockReturnValueOnce(Promise.resolve(mockedTransactionsResponse));
+
+  const result = await getWalletData('non-existing-address');
+  expect(result).toStrictEqual([Status.ERROR, null, null]);
+});