From 23d923cf71262f913098d29bd2b813fb13dda58b Mon Sep 17 00:00:00 2001
From: Jakob Odersky <jakob@driver.xyz>
Date: Thu, 5 Oct 2017 15:07:09 -0700
Subject: Cross-build for Scala 2.11 and 2.12

---
 build.sbt                   | 3 ++-
 src/main/scala/Tracer.scala | 2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/build.sbt b/build.sbt
index 08efff3..8085b79 100644
--- a/build.sbt
+++ b/build.sbt
@@ -4,7 +4,8 @@ version in ThisBuild := {
   ("git describe --always --dirty=-SNAPSHOT --match v[0-9].*" !!).tail.trim
 }
 
-scalaVersion := "2.12.3"
+crossScalaVersions := Seq("2.11.11", "2.12.3")
+scalaVersion := crossScalaVersions.value.last
 
 libraryDependencies ++= Seq(
   "com.pauldijou" %% "jwt-core" % "0.14.0",
diff --git a/src/main/scala/Tracer.scala b/src/main/scala/Tracer.scala
index 3d82489..3eddc1d 100644
--- a/src/main/scala/Tracer.scala
+++ b/src/main/scala/Tracer.scala
@@ -13,6 +13,6 @@ trait Tracer {
   def submit(span: Span): Unit
 
   /** Aggregate any potentially queued submissions and perform any cleanup logic. */
-  def close(): Future[_] = Future.unit
+  def close(): Future[_] = Future.successful(())
 
 }
-- 
cgit v1.2.3