add operators

Author: andersonkmi

src/main/scala/org/codecraftlabs/training/Rational.scala

@@ -13,10 +13,14 @@ class Rational (n: Int, d: Int) {
 
   override def toString: String = numer + "/" + denom
 
-  def add(that: Rational): Rational = {
+  def + (that: Rational): Rational = {
     new Rational (numer * that.denom + that.numer * denom, denom * that.denom)
   }
 
+  def * (that: Rational): Rational = {
+    new Rational(numer * that.denom, denom * that.numer)
+  }
+
   def lessThan(that: Rational): Boolean = {
     this.numer * that.denom < that.numer * this.denom
   }

src/test/scala/org/codecraftlabs/training/RationalSpec.scala

@@ -8,11 +8,20 @@ class RationalSpec extends AnyFlatSpec with Matchers {
     val r1 = new Rational(1, 2)
     val r2 = new Rational(2, 3)
 
-    val result = r1.add(r2)
+    val result = r1 + r2
     result.numer shouldEqual 7
     result.denom shouldEqual 6
   }
 
+  "1/3 * 1/6" should "result in 2" in {
+    val r1 = new Rational(1, 3)
+    val r2 = new Rational(1, 6)
+
+    val result = r1 * r2
+    result.numer shouldEqual 2
+    result.denom shouldEqual 1
+  }
+
   "1/3 lessThan 1/2" should "return true" in {
     val r1 = new Rational(1, 3)
     val r2 = new Rational(1, 2)