test: add test codes for VerifyContactEmailUseCase

src/test/kotlin/com/dobby/backend/application/usecase/member/VerifyContactEmailUseCaseTest.kt

@@ -0,0 +1,41 @@
+package com.dobby.backend.application.usecase.member
+
+import com.dobby.backend.domain.exception.SignupContactEmailDuplicateException
+import com.dobby.backend.domain.gateway.member.MemberGateway
+import io.kotest.core.spec.style.BehaviorSpec
+import io.kotest.matchers.shouldBe
+import io.kotest.assertions.throwables.shouldThrow
+import io.mockk.every
+import io.mockk.mockk
+
+class VerifyContactEmailUseCaseTest : BehaviorSpec({
+
+    val memberGateway = mockk<MemberGateway>()
+    val verifyContactEmailUseCase = VerifyContactEmailUseCase(memberGateway)
+
+    given("회원 가입 시 이메일 중복 확인") {
+
+        `when`("이메일이 데이터베이스에 존재하지 않는 경우") {
+            val input = VerifyContactEmailUseCase.Input(contactEmail = "[email protected]")
+
+            every { memberGateway.findByContactEmail(input.contactEmail) } returns null
+
+            then("이메일 사용 가능 응답을 반환해야 한다") {
+                val result = verifyContactEmailUseCase.execute(input)
+                result.success shouldBe true
+            }
+        }
+
+        `when`("이메일이 이미 존재하는 경우") {
+            val input = VerifyContactEmailUseCase.Input(contactEmail = "[email protected]")
+
+            every { memberGateway.findByContactEmail(input.contactEmail) } returns mockk()
+
+            then("SignupContactEmailDuplicateException 예외가 발생해야 한다") {
+                shouldThrow<SignupContactEmailDuplicateException> {
+                    verifyContactEmailUseCase.execute(input)
+                }
+            }
+        }
+    }
+})