KTLN-461: Check if an Enum Value Contains a Given String in Kotlin (#814)

* pom kotlin version

* pom version

* unit test code

* fixed unit test code

Author: nappy29

core-kotlin-modules/core-kotlin-datastructures-2/src/test/kotlin/com/baeldung/enumValueContainsString/EnumValueContainsStringUnitTest.kt

@@ -0,0 +1,84 @@
+package com.baeldung.enumValueContainsString
+
+import org.junit.jupiter.api.Assertions.assertFalse
+import org.junit.jupiter.api.Assertions.assertTrue
+import org.junit.jupiter.api.Test
+
+class EnumValueContainsStringUnitTest {
+
+    @Test
+    fun `checks if enum value contains a specific string correctly using for loop`() {
+        assertFalse(containsValueUsingForLoop("RED"))
+        assertTrue(containsValueUsingForLoop("WEDNESDAY"))
+        assertFalse(containsValueUsingForLoop("AUGUST"))
+        assertTrue(containsValueUsingForLoop("SATURDAY"))
+    }
+
+    @Test
+    fun `checks if enum value contains a specific string correctly using when expression`() {
+        assertFalse(containsValueUsingWhenExpression("RED"))
+        assertTrue(containsValueUsingWhenExpression("WEDNESDAY"))
+        assertFalse(containsValueUsingWhenExpression("AUGUST"))
+        assertTrue(containsValueUsingWhenExpression("SATURDAY"))
+    }
+
+    @Test
+    fun `checks if enum value contains a specific string correctly using any method`() {
+        val names = DaysOfWeek.values()
+
+        assertFalse(names.any { it.name == "RED" })
+        assertTrue(names.any { it.name == "WEDNESDAY" })
+        assertFalse(names.any { it.name == "AUGUST" })
+        assertTrue(names.any { it.name == "SATURDAY" })
+    }
+
+    @Test
+    fun `checks if enum value contains a specific string correctly using map method`() {
+        val names = DaysOfWeek.values().map { it.name}
+
+        assertFalse(names.contains("RED"))
+        assertTrue(names.contains("WEDNESDAY"))
+        assertFalse(names.contains("AUGUST"))
+        assertTrue(names.contains("SATURDAY"))
+    }
+
+    @Test
+    fun `checks if enum value contains a specific string correctly using a hashset`() {
+        assertFalse(containsValueUsingHashSet("RED"))
+        assertTrue(containsValueUsingHashSet("WEDNESDAY"))
+        assertFalse(containsValueUsingHashSet("AUGUST"))
+        assertTrue(containsValueUsingHashSet("SATURDAY"))
+    }
+
+}
+enum class DaysOfWeek {
+    MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY, SUNDAY;
+
+    companion object {
+        // generate names once.
+        val names by lazy { DaysOfWeek.values().map{ it.name } }
+    }
+}
+
+
+fun containsValueUsingForLoop(value: String): Boolean {
+    for (day in DaysOfWeek.values()) {
+        if (day.name == value) {
+            return true
+        }
+    }
+    return false
+}
+
+fun containsValueUsingWhenExpression(value: String): Boolean {
+    return when (value) {
+        in DaysOfWeek.names -> true
+        else -> false
+    }
+}
+
+fun containsValueUsingHashSet(value: String): Boolean {
+    val set = HashSet<String>()
+    DaysOfWeek.values().forEach { set.add(it.name) }
+    return set.contains(value)
+}