From bbf90b9f45576928652ac66df591103931b9fcd2 Mon Sep 17 00:00:00 2001
From: Chris Birchall <chris.birchall@gmail.com>
Date: Tue, 15 Jan 2019 21:43:25 +0000
Subject: [PATCH] Add a unit test for ContT.defer

---
 tests/src/test/scala/cats/tests/ContTSuite.scala | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/tests/src/test/scala/cats/tests/ContTSuite.scala b/tests/src/test/scala/cats/tests/ContTSuite.scala
index e4e6e28585..af8df13cea 100644
--- a/tests/src/test/scala/cats/tests/ContTSuite.scala
+++ b/tests/src/test/scala/cats/tests/ContTSuite.scala
@@ -64,4 +64,19 @@ class ContTSuite extends CatsSuite {
     withContLaw[Eval, Int, String, Int]
   }
 
+  test("ContT.defer defers evaluation until run is invoked") {
+    forAll { (b: Int, cb: Int => Eval[String]) =>
+      var didSideEffect = false
+
+      val contT = ContT.defer[Eval, String, Int] {
+        didSideEffect = true
+        b
+      }
+      didSideEffect should ===(false)
+
+      contT.run(cb)
+      didSideEffect should ===(true)
+    }
+  }
+
 }