Unit Test Training

Refactoring/Authenticator.cs

@@ -24,7 +24,7 @@ private User FindUserByCredentials(string username, string password)
         {
             if (IsValidUsername(username)) 
             {
-                return users.FirstOrDefault(user => user.Name.Equals(username) && (password == null || user.Password.Equals(password)));
+                return users.FirstOrDefault(user => user.Name.Equals(username) && password != null && user.Password.Equals(password));
             }
             else
             {

Refactoring/Store.cs

@@ -32,7 +32,7 @@ public void Purchase(string productId, int quantity)
                 throw new OutOfStockException();
             }
 
-            product.Quantity = product.Quantity - quantity+1;
+            product.Quantity = product.Quantity - quantity;
             user.Balance = user.Balance - product.Price * quantity;
 
             dataManager.SaveUser(user);

UnitTestProject/AuthenticatorTests.cs

@@ -0,0 +1,121 @@
+using Newtonsoft.Json;
+using NUnit.Framework;
+using Refactoring;
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace UnitTestProject
+{
+    [TestFixture]
+    class AuthenticatorTests
+    {
+        private Authenticator authenticator;
+
+        private User createTestUser(string name, string password, double balance)
+        {
+            User testUser = new User();
+            testUser.Name = name;
+            testUser.Password = password;
+            testUser.Balance = balance;
+
+            return testUser;
+        }
+
+        private List<User> CreateTestUserList()
+        {
+            var users = new List<User>();
+            users.Add(createTestUser("Test User", "TestPassWord", 5.01));
+            users.Add(createTestUser("Test User2", "TestPassWord2", 0.00));
+            return users;
+        }
+
+        private Authenticator CreateAuthenticator(List<User> users)
+        {  
+            return new Authenticator(users);
+        }
+
+        [Test]
+        public void Test_AuthenticateValidUser()
+        {
+            string userName = "Test User";
+            string userPassword = "TestPassWord";
+
+            User user = authenticator.Authenticate(userName, userPassword);
+            Assert.IsNotNull(user);
+            Assert.AreEqual(userName, user.Name);
+            Assert.AreEqual(userPassword, user.Password);
+        }
+
+        [Test]
+        public void Test_RejectInvalidUsername()
+        {
+            string userName = "Test User3";
+            string userPassword = "TestPassWord";
+
+            User user = authenticator.Authenticate(userName, userPassword);
+            Assert.IsNull(user);
+        }
+
+        [Test]
+        public void Test_RejectInvalidPassword()
+        {
+            string userName = "Test User2";
+            string userPassword = "TestPassWord";
+
+            User user = authenticator.Authenticate(userName, userPassword);
+            Assert.IsNull(user);
+        }
+
+        [Test]
+        public void Test_HandleNullInputs()
+        {
+            string userName = "Test User";
+            string userPassword = null;
+
+            User user = authenticator.Authenticate(userName, userPassword);
+            Assert.IsNull(user);
+
+            userName = null;
+            userPassword = null;
+
+            user = authenticator.Authenticate(userName, userPassword);
+            Assert.IsNull(user);
+        }
+
+        // THE BELOW CODE IS REQUIRED TO PREVENT THE TESTS FROM MODIFYING THE USERS/PRODUCTS ON FILE
+        //  This is not a good unit testing pattern - the unit test dependency on the file system should
+        //  actually be broken ... training on how to do this will be coming.
+        private List<User> originalUsers;
+        private List<Product> originalProducts;
+
+        [SetUp]
+        public void Test_Initialize()
+        {
+            // Load users from data file
+            originalUsers = JsonConvert.DeserializeObject<List<User>>(File.ReadAllText(@"Data/Users.json"));
+
+            // Load products from data file
+            originalProducts = JsonConvert.DeserializeObject<List<Product>>(File.ReadAllText(@"Data/Products.json"));
+
+            var users = CreateTestUserList();
+            authenticator = CreateAuthenticator(users);
+        }
+
+
+        [TearDown]
+        public void Test_Cleanup()
+        {
+            // Restore users
+            string json = JsonConvert.SerializeObject(originalUsers, Formatting.Indented);
+            File.WriteAllText(@"Data/Users.json", json);
+
+            // Restore products
+            string json2 = JsonConvert.SerializeObject(originalProducts, Formatting.Indented);
+            File.WriteAllText(@"Data/Products.json", json2);
+        }
+    }
+}

UnitTestProject/IntegrationTests.cs

@@ -10,7 +10,7 @@
 namespace UnitTestProject
 {
     [TestFixture]
-    //[Ignore("Disable integration tests")]
+    [Ignore("Disable integration tests")]
     public class IntegrationTests
     {
         private List<User> users;

UnitTestProject/StoreTests.cs

@@ -13,6 +13,8 @@ namespace UnitTestProject
     [TestFixture]
     class StoreTests
     {
+        const string TEST_PRODUCT_ID = "1";
+
         private User createTestUser(string name, string password, double balance)
         {
             User testUser = new User();
@@ -23,6 +25,13 @@ private User createTestUser(string name, string password, double balance)
             return testUser;
         }
 
+        private List<User> CreateTestUserList(double credit)
+        {
+            var users = new List<User>();
+            users.Add(createTestUser("Test User", "", credit));
+            return users;
+        }
+
         private Product createTestProduct(string id, string name, double price, int quantity)
         {
             Product testProduct = new Product();
@@ -34,20 +43,27 @@ private Product createTestProduct(string id, string name, double price, int quan
             return testProduct;
         }
 
-        [Test]
-        public void Test_PurchaseThrowsNoErrorForValidFunds()
+        private List<Product> CreateTestProductList(string productId, double price, int quantity)
         {
-            //Arrange
-            const string TEST_PRODUCT_ID = "1";
-
-            var users = new List<User>();
-            users.Add(createTestUser("Test User", "", 99.99));
-
             var products = new List<Product>();
-            products.Add(createTestProduct(TEST_PRODUCT_ID, "Product", 9.99, 10));
+            products.Add(createTestProduct(productId, "Product", price, quantity));
+            return products;
+        }
 
+        private static Store CreateStore(List<User> users, List<Product> products)
+        {
             var dataManager = new DataManager(users, products);
             var store = new Store(users[0], dataManager);
+            return store;
+        }
+
+        [Test]
+        public void Test_PurchaseThrowsNoErrorForValidFunds()
+        {
+            //Arrange
+            var users = CreateTestUserList(99.99);
+            var products = CreateTestProductList(TEST_PRODUCT_ID, 9.99, 10);
+            var store = CreateStore(users, products);
 
             //Act
             store.Purchase(TEST_PRODUCT_ID, 10);
@@ -60,37 +76,56 @@ public void Test_PurchaseThrowsNoErrorForValidFunds()
         public void Test_PurchaseRemovesProductFromStore()
         {
             //Arrange
+            var users = CreateTestUserList(99.99);
+            var products = CreateTestProductList(TEST_PRODUCT_ID, 9.99, 10);
+            var store = CreateStore(users, products);
 
             //Act
+            store.Purchase(TEST_PRODUCT_ID, 9);
 
             //Assert 
-            //(choose the appropriate statement(s))
-            //Assert.AreEqual(1, products[0].Quantity);
-            //Assert.AreSame(1, products[0].Quantity);
-            //Assert.IsTrue(products[0].Quantity == 1);
+            Assert.AreEqual(1, products[0].Quantity);
         }
 
         [Test]
         public void Test_PurchaseThrowsExceptionWhenBalanceIsTooLow()
         {
             //Arrange
+            var users = CreateTestUserList(1.00);
+            var products = CreateTestProductList(TEST_PRODUCT_ID, 1.01, 1);
+            var store = CreateStore(users, products);
 
             //Act
+            var ex = Assert.Throws<InsufficientFundsException>(() =>store.Purchase(TEST_PRODUCT_ID, 1));
 
             //Assert
+            Assert.AreEqual(1, products[0].Quantity);
         }
 
         [Test]
         public void Test_PurchaseThrowsExceptionWhenBalanceIsTooLowVersion2()
         {
             //Arrange
+            var users = CreateTestUserList(1.00);
+            var products = CreateTestProductList(TEST_PRODUCT_ID, 1.01, 1);
+            var store = CreateStore(users, products);
 
-            //Act
-
-            //Assert
+            //Act & Assert
+            var ex = Assert.Throws<InsufficientFundsException>(() => store.Purchase(TEST_PRODUCT_ID, 1));        
         }
 
+        [Test]
+        public void Test_PurchaseThrowsExceptionWhenOutOfStock()
+        {
+            //Arrange
+            const string TEST_PRODUCT_ID = "1";
+            var users = CreateTestUserList(5.00);
+            var products = CreateTestProductList(TEST_PRODUCT_ID, 1.01, 1);
+            var store = CreateStore(users, products);
 
+            //Act & Assert
+            var ex = Assert.Throws<OutOfStockException>(() => store.Purchase(TEST_PRODUCT_ID, 2));
+        }
         // THE BELOW CODE IS REQUIRED TO PREVENT THE TESTS FROM MODIFYING THE USERS/PRODUCTS ON FILE
         //  This is not a good unit testing pattern - the unit test dependency on the file system should
         //  actually be broken ... training on how to do this will be coming.

UnitTestProject/UnitTestProject.csproj

@@ -70,6 +70,7 @@
     <Otherwise />
   </Choose>
   <ItemGroup>
+    <Compile Include="AuthenticatorTests.cs" />
     <Compile Include="StoreTests.cs" />
     <Compile Include="IntegrationTests.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />