add tests for ShopController

src/test/kotlin/com/example/demo/DemoApplicationTests.kt

@@ -1,13 +0,0 @@
-package com.example.demo
-
-import org.junit.jupiter.api.Test
-import org.springframework.boot.test.context.SpringBootTest
-
-@SpringBootTest
-class DemoApplicationTests {
-
-	@Test
-	fun contextLoads() {
-	}
-
-}

src/test/kotlin/com/example/demo/controllers/GreetingControllerTest.kt

@@ -11,7 +11,6 @@ import kotlin.test.Test
 
 @WebMvcTest(GreetingController::class)
 class GreetingControllerTest(@Autowired val mockMvc: MockMvc) {
-
     @Test
     fun greetings_shouldSeeGreetingMessage() {
         mockMvc.perform(get("/greeting"))

src/test/kotlin/com/example/demo/controllers/ShopControllerTest.kt

@@ -0,0 +1,58 @@
+package com.example.demo.controllers
+
+import com.example.demo.models.*
+import com.example.demo.provider.ShopProvider
+import org.mockito.kotlin.doReturn
+import org.mockito.kotlin.whenever
+import org.springframework.beans.factory.annotation.Autowired
+import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest
+import org.springframework.boot.test.mock.mockito.MockBean
+import org.springframework.test.web.servlet.MockMvc
+import org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get
+import org.springframework.test.web.servlet.result.MockMvcResultMatchers.content
+import org.springframework.test.web.servlet.result.MockMvcResultMatchers.status
+import kotlin.test.Test
+
+@WebMvcTest(ShopController::class)
+class ShopControllerTest(@Autowired val mockMvc: MockMvc) {
+    @MockBean
+    private lateinit var shopProvider: ShopProvider
+
+    @Test
+    fun commonInfo_shouldSeeSuccessResponseJson() {
+        val shopMock = Shop(name="shop", customers= listOf(
+            Customer(
+                name = "cus-one",
+                city = City(name= "city-one"),
+                orders = listOf(
+                    Order(products = listOf(Product(name = "one", price = 11.2)), isDelivered = false),
+                    Order(products = listOf(Product(name = "two", price = 13.2)), isDelivered = false),
+                    Order(products = listOf(Product(name = "three", price = 15.2)), isDelivered = true),
+                )
+            ),
+            Customer(
+                name = "cus-two",
+                city = City(name= "city-two"),
+                orders = listOf(
+                    Order(products = listOf(Product(name = "one", price = 12.2)), isDelivered = false),
+                    Order(products = listOf(Product(name = "two", price = 13.2)), isDelivered = true),
+                    Order(products = listOf(Product(name = "four", price = 14.2)), isDelivered = true),
+                )
+            ),
+        ))
+
+        val expectedJson: String = """{
+            |"customers": {"withMoreUndeliveredOrdersThanDelivered": ["cus-one"]},
+            |"products": {"orderedByAllCustomers": ["two"]}
+            |}""".trimMargin()
+
+        whenever(
+            shopProvider.getRandomShop()
+        ) doReturn (shopMock)
+
+        mockMvc.perform(get("/shop/common-info"))
+            .andExpect(status().isOk)
+            .andExpect(content().contentType("application/json"))
+            .andExpect(content().json(expectedJson))
+    }
+}