add productService test

ShoppingCart/Backend/src/main/java/com/yen/ShoppingCart/service/ProductService.java

@@ -22,7 +22,6 @@ public void addProduct(ProductDto productDto, Category category) {
 
         Product product = getProductFromDto(productDto, category);
         productRepository.save(product);
-
     }
 
     // local method

ShoppingCart/Backend/src/test/java/com/yen/ShoppingCart/service/ProductServiceTest.java

@@ -0,0 +1,94 @@
+package com.yen.ShoppingCart.service;
+
+import com.yen.ShoppingCart.model.Category;
+import com.yen.ShoppingCart.model.Product;
+import com.yen.ShoppingCart.model.dto.product.ProductDto;
+import com.yen.ShoppingCart.repository.ProductRepository;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.Mockito;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
+class ProductServiceTest {
+
+    @Mock
+    ProductRepository productRepository;
+
+    @InjectMocks
+    ProductService productService;
+
+    Product product;
+
+    ProductDto productDto;
+
+    Category category;
+
+    List<Product> productList;
+
+    @BeforeEach
+    public void setUp(){
+
+        System.out.println("setup ...");
+        // public Product(String name, String imageURL, double price, String description, Category category) {
+        Category category = new Category();
+        product = new Product("prod_name","img_url", 100.0, "some desp", category);
+        productDto = new ProductDto(product);
+
+        productList = new ArrayList<>();
+        for (int i = 0; i < 3; i++){
+            productList.add(product);
+        }
+    }
+
+    @Test
+    public void testAddProductSuccess(){
+
+        // TODO : adjust test logic
+        Mockito.when(productRepository.save(product)).thenReturn(product);
+        productService.addProduct(productDto, category);
+    }
+
+    @Test
+    public void testGetProductFromDto(){
+
+        Product receivedProd = ProductService.getProductFromDto(productDto, category);
+        assertEquals(receivedProd.getName(), "prod_name");
+        assertEquals(receivedProd.getImageURL(), "img_url");
+        assertEquals(receivedProd.getPrice(), 100.0);
+        assertEquals(receivedProd.getDescription(), "some desp");
+        assertEquals(receivedProd.getCategory(), null);
+    }
+
+    @Test
+    public void ShouldReturnProductList(){
+
+        Mockito.when(productRepository.findAll()).thenReturn(productList);
+        List<ProductDto> res = productService.listProducts();
+        assertEquals(res.size(), 3);
+        assertEquals(res.get(0).getPrice(), 100.0);
+        assertEquals(res.get(0).getName(), "prod_name");
+        assertEquals(res.get(0).getImageURL(), "img_url");
+        assertEquals(res.get(0).getDescription(), "some desp");
+    }
+
+    @Test
+    public void ShouldReturnNullIfNullProductList(){
+
+        Mockito.when(productRepository.findAll()).thenReturn(new ArrayList<>());
+        List<ProductDto> res = productService.listProducts();
+        assertEquals(res.size(), 0);
+    }
+
+}