Added ShoppingListController unit tests

src/test/java/ntnu/idatt2016/v233/SmartMat/controller/ShoppingListControllerTest.java

+package ntnu.idatt2016.v233.SmartMat.controller;
+
+import ntnu.idatt2016.v233.SmartMat.dto.request.ShoppingListRequest;
+import ntnu.idatt2016.v233.SmartMat.entity.ShoppingList;
+import ntnu.idatt2016.v233.SmartMat.service.ShoppingListService;
+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.junit.jupiter.MockitoExtension;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+
+import java.util.Optional;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.mockito.Mockito.when;
+
+@ExtendWith(MockitoExtension.class)
+public class ShoppingListControllerTest {
+
+    @InjectMocks
+    private ShoppingListController shoppingListController;
+
+    @Mock
+    private ShoppingListService shoppingListService;
+
+    private ShoppingList shoppingList;
+
+    @BeforeEach
+    public void setUp() {
+        shoppingList = new ShoppingList();
+        // Set properties for the shoppingList object
+    }
+
+    @Test
+    public void createShoppingList() {
+        ShoppingListRequest request = new ShoppingListRequest(1L);
+        // Set properties for the request object
+
+        when(shoppingListService.createShoppingList(request)).thenReturn(shoppingList);
+
+        ResponseEntity<ShoppingList> response = shoppingListController.createShoppingList(request);
+
+        assertEquals(HttpStatus.CREATED, response.getStatusCode());
+        assertEquals(shoppingList, response.getBody());
+    }
+
+    @Test
+    public void getShoppingListById_found() {
+        long id = 1;
+        when(shoppingListService.getShoppingListById(id)).thenReturn(Optional.of(shoppingList));
+
+        ResponseEntity<ShoppingList> response = shoppingListController.getShoppingListById(id);
+
+        assertEquals(HttpStatus.OK, response.getStatusCode());
+        assertEquals(shoppingList, response.getBody());
+    }
+
+    @Test
+    public void getShoppingListById_notFound() {
+        long id = 1;
+        when(shoppingListService.getShoppingListById(id)).thenReturn(Optional.empty());
+
+        ResponseEntity<ShoppingList> response = shoppingListController.getShoppingListById(id);
+
+        assertEquals(HttpStatus.NOT_FOUND, response.getStatusCode());
+    }
+
+    @Test
+    public void getAllShoppingListsByGroupId_found() {
+        long groupId = 1;
+        when(shoppingListService.getShoppingListByGroupId(groupId)).thenReturn(Optional.of(shoppingList));
+
+        ResponseEntity<ShoppingList> response = shoppingListController.getAllShoppingListsByGroupId(groupId);
+
+        assertEquals(HttpStatus.OK, response.getStatusCode());
+        assertEquals(shoppingList, response.getBody());
+    }
+
+    @Test
+    public void getAllShoppingListsByGroupId_notFound() {
+        long groupId = 1;
+        when(shoppingListService.getShoppingListByGroupId(groupId)).thenReturn(Optional.empty());
+
+        ResponseEntity<ShoppingList> response = shoppingListController.getAllShoppingListsByGroupId(groupId);
+
+        assertEquals(HttpStatus.NOT_FOUND, response.getStatusCode());
+    }
+}