Make SCALAJS_VERSION more robust

.travis.yml

@@ -13,7 +13,7 @@ env:
     - TRAVIS_NODE_VERSION="12.16.1" JOB_NAME="test"
   matrix:
     - SCALAJS_VERSION="0.6.32"
-    - SCALAJS_VERSION="1.0.1"
+    - SCALAJS_VERSION=""
 
 script:
   - sbt ++$TRAVIS_SCALA_VERSION test

project/MySettings.scala

@@ -57,7 +57,7 @@ object MySettings {
 
   lazy val commonScalaJsSettings = Seq(
     scalacOptions ++= Seq("-P:scalajs:sjsDefinedByDefault").filter { _ =>
-      Option(System.getenv("SCALAJS_VERSION")).getOrElse("1.0.1").startsWith("0.6.")
+      Option(System.getenv("SCALAJS_VERSION")).filter(_.nonEmpty).getOrElse("1.0.1").startsWith("0.6.")
     },
     scalaJSLinkerConfig ~= {
       _.withModuleKind(ModuleKind.CommonJSModule)

project/plugins.sbt

@@ -1,5 +1,5 @@
 val scalaJSVersion =
-  Option(System.getenv("SCALAJS_VERSION")).getOrElse("1.0.1")
+  Option(System.getenv("SCALAJS_VERSION")).filter(_.nonEmpty).getOrElse("1.0.1")
 
 addSbtPlugin("org.scala-js"      % "sbt-scalajs"   % scalaJSVersion)
 addSbtPlugin("org.scalameta"     % "sbt-scalafmt"  % "2.4.0")

script/release.sh

@@ -4,5 +4,5 @@ cat ./version.sbt
 
 export SCALAJS_VERSION=0.6.32
 sbt clean +publishSigned sonatypeBundleUpload sonatypeReleaseAll
-export SCALAJS_VERSION=1.0.1
+unset SCALAJS_VERSION
 sbt clean +publishSigned sonatypeBundleUpload sonatypeReleaseAll