[#52] feat: FollowingUser 일급컬랙션 분리 및 isFollow 테스트

src/main/java/com/study/realworld/user/domain/FollowingUsers.java

@@ -0,0 +1,77 @@
+package com.study.realworld.user.domain;
+
+import com.study.realworld.global.exception.BusinessException;
+import com.study.realworld.global.exception.ErrorCode;
+import java.util.HashSet;
+import java.util.Objects;
+import java.util.Set;
+import javax.persistence.CascadeType;
+import javax.persistence.Embeddable;
+import javax.persistence.JoinColumn;
+import javax.persistence.JoinTable;
+import javax.persistence.ManyToMany;
+
+@Embeddable
+public class FollowingUsers {
+
+    @JoinTable(name = "follow",
+        joinColumns = @JoinColumn(name = "user_id"),
+        inverseJoinColumns = @JoinColumn(name = "follower_id"))
+    @ManyToMany(cascade = CascadeType.ALL)
+    private Set<User> followingUsers = new HashSet<>();
+
+    protected FollowingUsers() {
+    }
+
+    private FollowingUsers(Set<User> followingUsers) {
+        this.followingUsers = followingUsers;
+    }
+
+    public static FollowingUsers of(Set<User> followingUsers) {
+        return new FollowingUsers(followingUsers);
+    }
+
+    public boolean isFollow(User user) {
+        return followingUsers.contains(user);
+    }
+
+    public void followingUser(User user) {
+        checkFollowingUser(user);
+        followingUsers.add(user);
+    }
+
+    private void checkFollowingUser(User user) {
+        if (followingUsers.contains(user)) {
+            throw new BusinessException(ErrorCode.INVALID_FOLLOW);
+        }
+    }
+
+    public void unfollowingUser(User user) {
+        checkUnfollowingUser(user);
+        followingUsers.remove(user);
+    }
+
+    private void checkUnfollowingUser(User user) {
+        if (!followingUsers.contains(user)) {
+            throw new BusinessException(ErrorCode.INVALID_UNFOLLOW);
+        }
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
+        FollowingUsers that = (FollowingUsers) o;
+        return Objects.equals(followingUsers, that.followingUsers);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(followingUsers);
+    }
+
+}

src/main/java/com/study/realworld/user/domain/User.java

@@ -1,19 +1,11 @@
 package com.study.realworld.user.domain;
 
-import com.study.realworld.global.exception.BusinessException;
-import com.study.realworld.global.exception.ErrorCode;
-import java.util.HashSet;
 import java.util.Objects;
-import java.util.Set;
-import javax.persistence.CascadeType;
 import javax.persistence.Embedded;
 import javax.persistence.Entity;
 import javax.persistence.GeneratedValue;
 import javax.persistence.GenerationType;
 import javax.persistence.Id;
-import javax.persistence.JoinColumn;
-import javax.persistence.JoinTable;
-import javax.persistence.ManyToMany;
 import javax.persistence.Table;
 import org.springframework.security.crypto.password.PasswordEncoder;
 
@@ -34,11 +26,8 @@ public class User {
     @Embedded
     private Password password;
 
-    @JoinTable(name = "follow",
-        joinColumns = @JoinColumn(name = "user_id"),
-        inverseJoinColumns = @JoinColumn(name = "follower_id"))
-    @ManyToMany(cascade = CascadeType.ALL)
-    private Set<User> followingUsers = new HashSet<>();
+    @Embedded
+    private FollowingUsers followingUsers = new FollowingUsers();
 
     protected User() {
     }
@@ -107,29 +96,15 @@ public Profile profile() {
     }
 
     public boolean isFollow(User user) {
-        return followingUsers.contains(user);
+        return followingUsers.isFollow(user);
     }
 
     public void followingUser(User user) {
-        checkFollowingUser(user);
-        followingUsers.add(user);
-    }
-
-    private void checkFollowingUser(User user) {
-        if (followingUsers.contains(user)) {
-            throw new BusinessException(ErrorCode.INVALID_FOLLOW);
-        }
+        followingUsers.followingUser(user);
     }
 
     public void unfollowingUser(User user) {
-        checkUnfollowingUser(user);
-        followingUsers.remove(user);
-    }
-
-    private void checkUnfollowingUser(User user) {
-        if (!followingUsers.contains(user)) {
-            throw new BusinessException(ErrorCode.INVALID_UNFOLLOW);
-        }
+        followingUsers.unfollowingUser(user);
     }
 
     @Override

src/test/java/com/study/realworld/user/domain/FollowingUsersTest.java

@@ -0,0 +1,68 @@
+package com.study.realworld.user.domain;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.util.HashSet;
+import java.util.Set;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+
+class FollowingUsersTest {
+
+    private User user;
+    private User followingUser;
+
+    @BeforeEach
+    void beforeEach() {
+        user = User.Builder()
+            .profile(Username.of("username"), null, null)
+            .password(Password.of("password"))
+            .email(Email.of("[email protected]"))
+            .build();
+        followingUser = User.Builder()
+            .profile(Username.of("followingUser"), null, null)
+            .password(Password.of("password"))
+            .email(Email.of("[email protected]"))
+            .build();
+    }
+
+    @Nested
+    @DisplayName("follow 여부를 확인할 수 있다.")
+    class isFollowTest {
+
+        @Test
+        @DisplayName("follow된 상태일 때 true여야 한다.")
+        void trueTest() {
+
+            // given
+            Set<User> userSet = new HashSet<>();
+            userSet.add(followingUser);
+            FollowingUsers followingUsers = FollowingUsers.of(userSet);
+
+            // when
+            boolean result = followingUsers.isFollow(followingUser);
+
+            // then
+            assertTrue(result);
+        }
+
+        @Test
+        @DisplayName("follow안된 상태일 때 false여야 한다.")
+        void falseTest() {
+
+            // given
+            Set<User> userSet = new HashSet<>();
+            FollowingUsers followingUsers = FollowingUsers.of(userSet);
+
+            // when
+            boolean result = followingUsers.isFollow(followingUser);
+
+            // then
+            assertFalse(result);
+        }
+    }
+
+}