test: Added tests

- added the Order, Voucher tests
- added the synchronisation test
- added application.yml for the test profile

src/test/java/com/f_lab/la_planete/domain/OrderTest.java

@@ -0,0 +1,69 @@
+package com.f_lab.la_planete.domain;
+
+import org.assertj.core.api.Assertions;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import java.math.BigDecimal;
+import java.math.RoundingMode;
+import java.time.LocalDateTime;
+import java.time.Month;
+
+
+class OrderTest {
+
+  Currency KRW = Currency.builder()
+      .currencyCode("KRW")
+      .currencySymbol("₩")
+      .roundingScale(0)
+      .roundingMode(RoundingMode.FLOOR)
+      .build();
+
+  Food food = Food.builder()
+      .price(BigDecimal.valueOf(10000))
+      .currency(KRW)
+      .totalQuantity(1000)
+      .build();
+
+  Voucher voucher = Voucher.builder()
+      .discountRate(BigDecimal.valueOf(0.45))
+      .expiryDate(LocalDateTime.of(3000, Month.DECEMBER, 12, 23, 59))
+      .build();
+
+  @Test
+  @DisplayName("할인 쿠폰이 있는 경우에 calculateTotalCost() 메서드")
+  void test_totalCost_given_food_and_voucher_success() {
+    // given
+    BigDecimal totalCost = food.calculateCost(3);
+    Order order = Order.builder()
+        .food(food)
+        .totalCost(totalCost)
+        .quantity(3)
+        .voucher(voucher)
+        .build();
+
+    // when
+    BigDecimal calculatedTotalCost = order.calculateTotalCost();
+
+    // then
+    Assertions.assertThat(calculatedTotalCost).isEqualTo(BigDecimal.valueOf(16500));
+  }
+
+  @Test
+  @DisplayName("할인 쿠폰이 없는 경우에 calculateTotalCost() 메서드")
+  void test_totalCost_given_food_and_without_voucher_success() {
+    // given
+    BigDecimal totalCost = food.calculateCost(3);
+    Order order = Order.builder()
+        .food(food)
+        .totalCost(totalCost)
+        .quantity(3)
+        .build();
+
+    // when
+    BigDecimal calculatedTotalCost = order.calculateTotalCost();
+
+    // then
+    Assertions.assertThat(calculatedTotalCost).isEqualTo(BigDecimal.valueOf(30000));
+  }
+}

src/test/java/com/f_lab/la_planete/domain/VoucherTest.java

@@ -0,0 +1,58 @@
+package com.f_lab.la_planete.domain;
+
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import java.math.BigDecimal;
+import java.math.RoundingMode;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
+class VoucherTest {
+  Currency GBP = Currency.builder()
+      .currencyCode("GBP")
+      .currencySymbol("£")
+      .roundingScale(2)
+      .roundingMode(RoundingMode.FLOOR)
+      .build();
+
+  Currency KRW = Currency.builder()
+      .currencyCode("KRW")
+      .currencySymbol("₩")
+      .roundingScale(0)
+      .roundingMode(RoundingMode.FLOOR)
+      .build();
+
+  @Test
+  @DisplayName("0 ~ 100 사이의 값이 들어올 때 정상적으로 할인이 적용된 값을 return")
+  void test_voucher_discount_success() {
+    // given
+    Voucher voucher = new Voucher();
+    voucher.setDiscountRate(BigDecimal.valueOf(0.25));
+
+    // when
+    BigDecimal afterDiscountsGBP1 = voucher.apply(BigDecimal.valueOf(100), GBP);
+    BigDecimal afterDiscountsGBP2 = voucher.apply(BigDecimal.valueOf(500.4), GBP);
+    BigDecimal afterDiscountsKRW3 = voucher.apply(BigDecimal.valueOf(100), KRW);
+
+    // then
+    assertThat(afterDiscountsGBP1).isEqualTo(BigDecimal.valueOf(75.00).setScale(2));
+    assertThat(afterDiscountsGBP2).isEqualTo(BigDecimal.valueOf(375.30).setScale(2));
+    assertThat(afterDiscountsKRW3).isEqualTo(BigDecimal.valueOf(75));
+  }
+
+  @Test
+  @DisplayName("currency 값에 null 값이 들어갔을 경우에 예외를 던진다.")
+  void test_voucher_discount_failure() {
+    // given
+    Voucher voucher = new Voucher();
+    voucher.setDiscountRate(BigDecimal.valueOf(0.25));
+
+    // when
+    assertThatThrownBy(() ->
+        voucher.apply(BigDecimal.valueOf(100), null)
+    ).isInstanceOf(IllegalStateException.class);
+
+  }
+}

src/test/java/com/f_lab/la_planete/resources/application.yml

@@ -0,0 +1,7 @@
+spring:
+  profiles:
+    active: test
+
+  jpa:
+    hibernate:
+      ddl-auto: create-drop

src/test/java/com/f_lab/la_planete/service/OrderServiceSynchronisationTest.java

@@ -0,0 +1,68 @@
+package com.f_lab.la_planete.service;
+
+import com.f_lab.la_planete.domain.Food;
+import com.f_lab.la_planete.dto.request.OrderCreateRequestDTO;
+import com.f_lab.la_planete.repository.FoodRepository;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+
+
+import java.math.BigDecimal;
+import java.util.concurrent.*;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@SpringBootTest
+class OrderServiceSynchronisationTest {
+
+  @Autowired
+  OrderService orderService;
+
+  @Autowired
+  FoodRepository foodRepository;
+
+  Food dummyFood = Food.builder()
+      .price(BigDecimal.valueOf(1000))
+      .totalQuantity(1000)
+      .build();
+
+  OrderCreateRequestDTO request = OrderCreateRequestDTO.builder()
+      .foodId(1L)
+      .price(BigDecimal.valueOf(1000))
+      .quantity(10)
+      .build();
+
+  @BeforeEach
+  void beforeEach() {
+    foodRepository.saveAndFlush(dummyFood);
+  }
+
+  @Test
+  @DisplayName("동시성 테스트 100개의 요청이 동시에 왔을 때 데이터의 일관성이 유지")
+  void test_concurrency_thread_100_success() throws InterruptedException {
+    // given
+    int count = 100;
+    CountDownLatch countDownLatch = new CountDownLatch(count);
+    ExecutorService executorService = Executors.newFixedThreadPool(count);
+
+    // when
+    for (int i = 0; i < count; i++) {
+      executorService.submit(() -> {
+        try {
+          orderService.createFoodOrder(request);
+        } finally {
+          countDownLatch.countDown();
+        }
+      });
+    }
+
+    countDownLatch.await();
+
+    // then
+    Food food = foodRepository.findById(1L).orElseThrow();
+    assertThat(food.getTotalQuantity()).isEqualTo(0L);
+  }
+}