refactor : 변수이름 변경 및 팩토리 사용

 - 알파벳 변수 이름 변경 _value -> alphabet
 - 알파벳 팩토리를 사용하도록 변경
 - 함수 위치 변경
 - 깨진 테스트 수정

src/main/kotlin/edu/nextstep/wordle/application/wordle/Word.kt

@@ -1,13 +1,20 @@
 package edu.nextstep.wordle.application.wordle
 
 import edu.nextstep.wordle.application.wordle.window.Alphabet
+import edu.nextstep.wordle.application.wordle.window.AlphabetFactory
 import edu.nextstep.wordle.application.wordle.window.Match
 import edu.nextstep.wordle.application.wordle.window.Window
 import edu.nextstep.wordle.application.wordle.window.WindowResult
 
 data class Word(
     val windows: Set<Window>,
 ) {
+    init {
+        if (this.windows.size != WORD_SIZE) {
+            throw IllegalArgumentException("${this.windows.size}: 단어의 사이즈는 ${WORD_SIZE}여야 합니다.")
+        }
+    }
+
     fun match(input: Word): List<WindowResult> {
         var results = listOf<WindowResult>()
 
@@ -30,18 +37,13 @@ data class Word(
         return windowResult
     }
 
-    init {
-        if (this.windows.size != WORD_SIZE) {
-            throw IllegalArgumentException("${this.windows.size}: 단어의 사이즈는 ${WORD_SIZE}여야 합니다.")
-        }
-    }
-
     companion object {
         private const val WORD_SIZE: Int = 5
 
         fun create(input: String): Word {
+            val alphabetFactory = AlphabetFactory.instance
             val windows = input.mapIndexed { index, alphabet ->
-                Window(alphabet = Alphabet(value = alphabet.toString()), position = index)
+                Window(alphabet = alphabetFactory.findBy(alphabet.toString()), position = index)
             }.toSet()
             return Word(windows)
         }

src/main/kotlin/edu/nextstep/wordle/application/wordle/Wordle.kt

@@ -23,7 +23,7 @@ data class Wordle(
     private fun WordFinder.notContain(word: Word): Boolean = !this.contain(word)
 
     private fun Word.rawWord(): String {
-        return windows.sortedBy { it.position }.joinToString(separator = "") { it.alphabet._value }
+        return windows.sortedBy { it.position }.joinToString(separator = "") { it.alphabet.alphabet }
     }
 
     fun isSuccess(): Boolean {

src/main/kotlin/edu/nextstep/wordle/application/wordle/window/Alphabet.kt

@@ -3,30 +3,30 @@ package edu.nextstep.wordle.application.wordle.window
 class Alphabet(
     value: String,
 ) {
-    val _value: String = value.lowercase()
+    val alphabet: String = value.lowercase()
 
     init {
-        if (!alphabets.contains(_value)) {
-            throw IllegalArgumentException("$_value 알파벳 입력만 허용합니다.")
+        if (!alphabets.contains(alphabet)) {
+            throw IllegalArgumentException("$alphabet 알파벳 입력만 허용합니다.")
         }
     }
 
-    companion object {
-        private val alphabets = ('A'..'Z').map { it.lowercase() }.toSet()
-    }
-
     override fun equals(other: Any?): Boolean {
         if (this === other) return true
         if (javaClass != other?.javaClass) return false
 
         other as Alphabet
 
-        if (_value != other._value) return false
+        if (alphabet != other.alphabet) return false
 
         return true
     }
 
     override fun hashCode(): Int {
-        return _value.hashCode()
+        return alphabet.hashCode()
+    }
+
+    companion object {
+        private val alphabets = ('A'..'Z').map { it.lowercase() }.toSet()
     }
 }

src/main/kotlin/edu/nextstep/wordle/application/wordle/window/AlphabetFactory.kt

@@ -9,7 +9,9 @@ class AlphabetFactory(
     }
 
     companion object {
-        fun create(): AlphabetFactory {
+        val instance = create()
+
+        private fun create(): AlphabetFactory {
             val alphabets: Set<Alphabet> = ('A'..'Z').map { Alphabet(it.lowercase()) }
                 .toSet()
 

src/test/kotlin/edu/nextstep/wordle/application/wordle/WordResultsTest.kt

@@ -7,7 +7,7 @@ internal class WordResultsTest {
     @Test
     fun `결과가 없다면 실패로 간주한다`() {
         //given
-        val result = WordResult(round = 0, windowResults = listOf())
+        val result = WordResults(emptyList())
 
         //when
         val success = result.isSuccess()

src/test/kotlin/edu/nextstep/wordle/application/wordle/WordleTest.kt

@@ -22,7 +22,7 @@ internal class WordleTest {
         //then
         assertThat(answer).isInstanceOf(WordleAnswer.Retry::class.java)
         assertThat(answer.wordle).isEqualTo(wordle)
-        assertThat((answer as WordleAnswer.Retry).message).isEqualTo("사전에 없는 단어($notExist)입니다.")
+        assertThat((answer as WordleAnswer.Retry).message).isEqualTo("사전에 없는 단어(asdfa)입니다.")
     }
 
     @Test

src/test/kotlin/edu/nextstep/wordle/application/wordle/window/AlphabetFactoryTest.kt

@@ -8,7 +8,7 @@ internal class AlphabetFactoryTest {
     @Test
     fun `팩토리를 통해 알파벳을 찾을 수 있다`() {
         //given
-        val alphabetFactory = AlphabetFactory.create()
+        val alphabetFactory = AlphabetFactory.instance
 
         //when
         val alphabet = alphabetFactory.findBy("a")