Introduce UserMapperTest

application/module-language-school/src/test/java/org/fuseri/modulelanguageschool/user/UserMapperTest.java

+package org.fuseri.modulelanguageschool.user;
+
+import org.fuseri.model.dto.user.AddressDto;
+import org.fuseri.model.dto.user.UserCreateDto;
+import org.fuseri.model.dto.user.UserDto;
+import org.fuseri.model.dto.user.UserType;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.data.domain.Page;
+import org.springframework.data.domain.PageImpl;
+import org.springframework.data.domain.PageRequest;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+@SpringBootTest
+class UserMapperTest {
+
+    @Autowired
+    private UserMapper userMapper;
+
+    private final UserDto userDto = new UserDto(
+            "xnovak", "xnovak@emample.com", "Peter", "Novak",
+            new AddressDto(), UserType.STUDENT);
+    private final UserCreateDto userCreateDto = new UserCreateDto(
+            "xnovak", "akfksobg",
+            "xnovak@emample.com", "Peter", "Novak", new AddressDto(), UserType.STUDENT, Map.of());
+
+    private final User userFromCreateDto = new User(
+            "xnovak", org.fuseri.modulelanguageschool.user.UserType.STUDENT, "akfksobg",
+            "xnovak@emample.com", "Peter", "Novak", new Address(), null, new HashMap<>());
+
+    private final User userFromDto = new User(
+            "xnovak", org.fuseri.modulelanguageschool.user.UserType.STUDENT, null,
+            "xnovak@emample.com", "Peter", "Novak", new Address(), null, null);
+
+    @Test
+    void nullFromCreateDto() {
+        User mappedUser = userMapper.fromCreateDto(null);
+        assertNull(mappedUser);
+    }
+
+    @Test
+    void fromCreateDto() {
+        User mappedUser = userMapper.fromCreateDto(userCreateDto);
+        assertEquals(userFromCreateDto, mappedUser);
+    }
+
+    @Test
+    void nullFromDto() {
+        User mappedUser = userMapper.fromDto(null);
+        assertNull(mappedUser);
+    }
+
+    @Test
+    void fromDto() {
+        User mappedUser = userMapper.fromDto(userDto);
+        assertEquals(userFromDto, mappedUser);
+    }
+
+    @Test
+    void nullToDto() {
+        var createdDto = userMapper.toDto(null);
+        assertNull(createdDto);
+    }
+
+    @Test
+    void toDto() {
+        var mappedDto = userMapper.toDto(userFromDto);
+        assertEquals(userDto, mappedDto);
+    }
+
+    @Test
+    void nullToDtoList() {
+        var mappedDtos = userMapper.toDtoList(null);
+        assertNull(mappedDtos);
+    }
+
+    @Test
+    void toEmptyDtoList() {
+        var mappedDtos = userMapper.toDtoList(Collections.emptyList());
+        assertTrue(mappedDtos.isEmpty());
+    }
+
+    @Test
+    void toDtoList() {
+        var mappedDtos = userMapper.toDtoList(List.of(userFromDto));
+        assertEquals(List.of(userDto), mappedDtos);
+    }
+
+    @Test
+    void toEmptyDtoPage() {
+        Page<UserDto> pageDto = userMapper.toDtoPage(Page.empty());
+        assertEquals(1, pageDto.getTotalPages());
+        assertTrue(pageDto.getContent().isEmpty());
+    }
+
+    @Test
+    void toDtoPage() {
+        List<User> users = List.of(userFromDto);
+        Page<User> page = new PageImpl<>(users, PageRequest.of(0, 10), users.size());
+        Page<UserDto> pageDto = userMapper.toDtoPage(page);
+
+        assertEquals(page.getTotalPages(), pageDto.getTotalPages());
+        assertEquals(page.getNumber(), pageDto.getNumber());
+        assertEquals(page.getNumberOfElements(), pageDto.getNumberOfElements());
+        assertEquals(page.getSize(), pageDto.getSize());
+        assertEquals(page.getTotalElements(), pageDto.getTotalElements());
+        assertEquals(List.of(userDto), pageDto.getContent());
+    }
+}
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