Merge pull request #741 from albertache1998/list-to-set

[KTLN-722] Add List Contents Into a Set in Kotlin

Author: davidmartinezbarua

core-kotlin-modules/core-kotlin-collections-set/src/test/kotlin/com/baeldung/addListToSet/AddListContentToSetUnitTest.kt

@@ -0,0 +1,53 @@
+package com.baeldung.addListToSet
+
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Test
+
+class AddListContentToSetUnitTest {
+
+    @Test
+    fun `test adding list contents to set programmatically`() {
+        val list = listOf("apple", "banana", "orange")
+        val set = addListToSet(list)
+        assertEquals(setOf("apple", "banana", "orange"), set)
+    }
+
+    @Test
+    fun `test adding list contents to set using addAll() method`() {
+        val list = listOf("apple", "banana", "orange")
+        val set = mutableSetOf<String>()
+        set.addAll(list)
+        assertEquals(setOf("apple", "banana", "orange"), set)
+    }
+
+    @Test
+    fun `test adding list contents to set using toSet() method`() {
+        val list = listOf("apple", "banana", "orange")
+        val set = list.toSet()
+        assertEquals(setOf("apple", "banana", "orange"), set)
+    }
+
+    @Test
+    fun `test adding list contents to set using plus operator`() {
+        val set = setOf<String>()
+        val list = listOf("apple", "banana", "orange")
+        val newSet = set + list
+        assertEquals(setOf("apple", "banana", "orange"), newSet)
+    }
+
+    @Test
+    fun `test adding list contents to set using union method`() {
+        val set = setOf<String>()
+        val list = listOf("apple", "banana", "orange")
+        val newSet = set.union(list)
+        assertEquals(setOf("apple", "banana", "orange"), newSet)
+    }
+
+    fun addListToSet(list: List<String>): Set<String> {
+        val set = mutableSetOf<String>()
+        for (element in list) {
+            set.add(element)
+        }
+        return set
+    }
+}