[SCALA-271] - Convert a Scala List to a Tuple

Author: Callum Gibbons

scala-core-collections-modules/scala-core-collections-4/src/main/scala/com/baeldung/scala/listtotuple/ConvertListToTuple.scala

@@ -0,0 +1,25 @@
+package com.baeldung.scala.listtotuple
+
+import scala.quoted.Expr
+
+object ConvertListToTuple {
+  def twoElementsToTuple(list: List[String]): (String, String) = {
+    val first :: second :: _ = list
+    (first, second)
+  }
+
+  def twoElementsToTupleUsingMatch(list: List[String]): (String, String) = {
+    list match {
+      case first :: second :: _ => (first, second)
+      case _ => ("", "")
+    }
+  }
+
+  def unknownSizeToTuple(list: List[String]): Tuple = {
+    list match {
+      case first :: second :: third :: _ => (first, second, third)
+      case first :: second :: _ => (first, second)
+      case _ => ("", "")
+    }
+  }
+}

scala-core-collections-modules/scala-core-collections-4/src/test/scala/com/baeldung/scala/listtotuple/ConvertListToTupleUnitTest.scala

@@ -0,0 +1,53 @@
+package com.baeldung.scala.listtotuple
+
+
+import org.scalatest.flatspec.AnyFlatSpec
+import org.scalatest.matchers.should.Matchers
+import org.scalatest.matchers.should.Matchers.shouldBe
+
+class ConvertListToTupleUnitTest extends AnyFlatSpec with Matchers {
+  "twoElementsToTuple" should "convert list with 2 elements" in {
+    val testList = List("Hello", "world")
+    ConvertListToTuple.twoElementsToTuple(testList) shouldBe ("Hello", "world")
+  }
+
+  "twoElementsToTuple" should "convert list with 3 elements to Tuple3" in {
+    val testList = List("Hello", "world", "!")
+    ConvertListToTuple.twoElementsToTuple(testList) shouldBe ("Hello", "world")
+  }
+
+  "twoElementsToTupleUsingMatch" should "convert list with 2 elements" in {
+    val testList = List("Hello", "world")
+    ConvertListToTuple.twoElementsToTupleUsingMatch(testList) shouldBe ("Hello", "world")
+  }
+
+  "twoElementsToTupleUsingMatch" should "convert list with 3 elements to tuple2 ignoring extra elements" in {
+    val testList = List("Hello", "world", "!")
+    ConvertListToTuple.twoElementsToTupleUsingMatch(testList) shouldBe ("Hello", "world")
+  }
+
+  "twoElementsToTupleUsingMatch" should "return empty Strings for 1 element" in {
+    val testList = List("Hello")
+    ConvertListToTuple.twoElementsToTupleUsingMatch(testList) shouldBe ("", "")
+  }
+
+  "twoElementsToTupleUsingMatch" should "return empty Strings for Nil" in {
+    val testList = Nil
+    ConvertListToTuple.twoElementsToTupleUsingMatch(testList) shouldBe ("", "")
+  }
+
+  "unknownSizeToTuple" should "return empty Strings for Nil" in {
+    val testList = Nil
+    ConvertListToTuple.unknownSizeToTuple(testList) shouldBe ("", "")
+  }
+
+  "unknownSizeToTuple" should "convert list of 2 elements to tuple2" in {
+    val testList = List("Hello", "world")
+    ConvertListToTuple.unknownSizeToTuple(testList) shouldBe ("Hello", "world")
+  }
+
+  "unknownSizeToTuple" should "convert list of 3 elements to tuple3" in {
+    val testList = List("Hello", "world", "!")
+    ConvertListToTuple.unknownSizeToTuple(testList) shouldBe ("Hello", "world", "!")
+  }
+}