[iterate-enum-items] iterate enum in kotlin

Author: sk1418

core-kotlin-modules/core-kotlin-lang-oop-4/src/test/kotlin/iterateEnumEntries/IterateEnumEntriesUnitTest.kt

@@ -1,23 +1,60 @@
 package iterateEnumEntries
 
-import iterateEnumEntries.DayInWeek.*
-import org.junit.jupiter.api.Assertions.assertArrayEquals
+import iterateEnumEntries.Holiday.*
+import iterateEnumEntries.Weekday.*
+import org.junit.jupiter.api.Assertions.*
 import org.junit.jupiter.api.Test
-import kotlin.test.assertEquals
 
-enum class DayInWeek {
-    MON, TUE, WED, THU, FRI, SAT, SUN
+enum class Weekday {
+    MON, TUE, WED, THU, FRI
+}
+
+enum class Holiday {
+    Eastern, Christmas, LaborDay, NewYear
 }
 
 class IterateEnumEntriesUnitTest {
-    val expectedArray = arrayOf(MON, TUE, WED, THU, FRI, SAT, SUN)
+    private val expectedWeekdayArray = arrayOf(MON, TUE, WED, THU, FRI)
+    private val expectedWeekdayList = listOf(MON, TUE, WED, THU, FRI)
+
+    private val expectedHolidayArray = arrayOf(Eastern, Christmas, LaborDay, NewYear)
 
     @Test
     fun `when using values() then get correct iterable`() {
-        val result = DayInWeek.values()
+        val result = Weekday.values()
+        assertArrayEquals(expectedWeekdayArray, result)
+    }
 
-        assertArrayEquals(expectedArray, result)
+    @Test
+    fun `when using entries() then get correct iterable`() {
+        val result = Weekday.entries
+        assertEquals(expectedWeekdayList, result)
+    }
+
+    @Test
+    fun `when using enumValues() then get correct iterable`() {
+        val weekdayResult = enumValues<Weekday>()
+        assertArrayEquals(expectedWeekdayArray, weekdayResult)
 
+        val holidayResult = enumValues<Holiday>()
+        assertArrayEquals(expectedHolidayArray, holidayResult)
     }
 
+    inline fun <reified E : Enum<E>> findEnumByName(name: String): E? {
+        // E.values() or E.entries doesn't compile
+        return enumValues<E>().firstOrNull { it.name.equals(name.replace(" ", ""), ignoreCase = true) }
+    }
+
+
+    @Test
+    fun `when using the generic itemNames then get correct iterable`() {
+        val tuesday = findEnumByName<Weekday>("t U e")
+        assertEquals(TUE, tuesday)
+
+        val newYear = findEnumByName<Holiday>("N E W Y E A R")
+        assertEquals(NewYear, newYear)
+
+        val unknown = findEnumByName<Holiday>("Thanksgiving")
+        assertNull(unknown)
+    }
 }