From 793b3e7f60a11007bdffa9d9ff40774c0e0cb141 Mon Sep 17 00:00:00 2001
From: Erik LaBianca <erik.labianca@gmail.com>
Date: Mon, 30 Nov 2015 19:07:59 -0500
Subject: [PATCH] Add getOrElseF method to XorT

---
 core/src/main/scala/cats/data/XorT.scala        | 7 +++++++
 tests/src/test/scala/cats/tests/XorTTests.scala | 6 ++++++
 2 files changed, 13 insertions(+)

diff --git a/core/src/main/scala/cats/data/XorT.scala b/core/src/main/scala/cats/data/XorT.scala
index 5bc5669bbe9..05321816531 100644
--- a/core/src/main/scala/cats/data/XorT.scala
+++ b/core/src/main/scala/cats/data/XorT.scala
@@ -22,6 +22,13 @@ final case class XorT[F[_], A, B](value: F[A Xor B]) {
 
   def getOrElse[BB >: B](default: => BB)(implicit F: Functor[F]): F[BB] = F.map(value)(_.getOrElse(default))
 
+  def getOrElseF[BB >: B](default: => F[BB])(implicit F: Monad[F]): F[BB] = {
+    F.flatMap(value) {
+      case Xor.Left(a) => default
+      case Xor.Right(a) => F.pure(a)
+    }
+  }
+
   def recover(pf: PartialFunction[A, B])(implicit F: Functor[F]): XorT[F, A, B] =
     XorT(F.map(value)(_.recover(pf)))
 
diff --git a/tests/src/test/scala/cats/tests/XorTTests.scala b/tests/src/test/scala/cats/tests/XorTTests.scala
index de5287af4d8..323888f8330 100644
--- a/tests/src/test/scala/cats/tests/XorTTests.scala
+++ b/tests/src/test/scala/cats/tests/XorTTests.scala
@@ -157,6 +157,12 @@ class XorTTests extends CatsSuite {
     }
   }
 
+  test("getOrElseF with Id consistent with Xor getOrElse") {
+    forAll { (xort: XorT[Id, String, Int], i: Int) =>
+      xort.getOrElseF(i) should === (xort.value.getOrElse(i))
+    }
+  }
+
   test("forall with Id consistent with Xor forall") {
     forAll { (xort: XorT[Id, String, Int], f: Int => Boolean) =>
       xort.forall(f) should === (xort.value.forall(f))