Merge pull request #1471 from yadavan88/string-concat

String concat operations in scala

Author: dominiqueplante

scala-core-modules/scala-strings-2/src/test/scala/com/baeldung/scala/strings/concatstrings/ConcatStringUnitTest.scala

@@ -0,0 +1,78 @@
+package com.baeldung.scala.strings.concatstrings
+
+import org.scalatest.flatspec.AnyFlatSpec
+import org.scalatest.matchers.should.Matchers
+
+class ConcatStringUnitTest extends AnyFlatSpec with Matchers {
+
+  it should "concat strings using + operator" in {
+    val str1 = "Hello"
+    val str2 = "Baeldung"
+    val combined = str1 + str2
+    combined shouldBe "HelloBaeldung"
+  }
+
+  it should "concat string with another type using + operator" in {
+    val str1 = "Hello"
+    val combined = str1 + 10
+    combined shouldBe "Hello10"
+  }
+
+  it should "concat strings using ++ operator" in {
+    val str1 = "Hello"
+    val str2 = "Baeldung"
+    val combined = str1 ++ str2
+    combined shouldBe "HelloBaeldung"
+  }
+
+  it should "concat strings using concat" in {
+    val str1 = "Hello"
+    val str2 = "Baeldung"
+    val combined = str1.concat(str2)
+    combined shouldBe "HelloBaeldung"
+  }
+
+  it should "concat strings using string interpolation" in {
+    val str1 = "Hello"
+    val str2 = "Baeldung"
+    val combined = s"$str1$str2"
+    combined shouldBe "HelloBaeldung"
+  }
+
+  it should "concat strings using multi line string interpolation" in {
+    val str1 = "Hello"
+    val str2 = "Baeldung"
+    val combined = s"""$str1$str2"""
+    combined shouldBe "HelloBaeldung"
+  }
+
+  it should "concat strings using StringBuilder" in {
+    val str1 = "Hello"
+    val str2 = "Baeldung"
+    val combined = new StringBuilder(str1).append(str2).toString()
+    combined shouldBe "HelloBaeldung"
+  }
+
+  it should "concat strings using mkString" in {
+    val strings = Seq("Hello", "Baeldung")
+    val combined = strings.mkString
+    combined shouldBe "HelloBaeldung"
+    strings.mkString(",") shouldBe "Hello,Baeldung"
+  }
+
+  it should "concat strings using reduce" in {
+    val strings = Seq("Hello", "Baeldung")
+    val combined = strings.reduce(_ + _)
+    combined shouldBe "HelloBaeldung"
+    val combinedWithComma = strings.reduce((a, b) => (a + "," + b))
+    combinedWithComma shouldBe "Hello,Baeldung"
+  }
+
+  it should "concat strings using foldLeft" in {
+    val strings = Seq("Hello", "Baeldung")
+    val combined = strings.foldLeft("")(_ + _)
+    combined shouldBe "HelloBaeldung"
+    List.empty[String].foldLeft("")(_ + _) shouldBe ""
+  }
+
+}