Version 0.6.0

README.md

@@ -16,3 +16,9 @@ addSbtPlugin("gs" % "sbt-garrity-software" % "0.4.0")
 ```scala
 ThisBuild / gsProjectName := "project-name"
 ```
+
+## Publishing
+
+```
+sbt -Dversion=$VERSION -Drelease=true publish
+```

src/main/scala/gs/GsKeys.scala

@@ -14,4 +14,8 @@ object GsKeys {
     "Name of the project and Git repository."
   )
 
+  lazy val writeScalaVersionToFile = taskKey[Unit](
+    "Task to emit the Scala version used to build this project to a file."
+  )
+
 }

src/main/scala/gs/GsPlugin.scala

@@ -1,5 +1,8 @@
 package gs
 
+import java.nio.charset.StandardCharsets
+import java.nio.file.Files
+import java.nio.file.Paths
 import sbt._
 import sbt.Keys._
 
@@ -10,6 +13,8 @@ object GsPlugin extends AutoPlugin {
 
   import autoImport._
 
+  val ScalaVersionFile: String = ".scala-version"
+
   override def projectSettings: Seq[Setting[_]] = Seq(
     publishMavenStyle           := true,
     Test / Keys.publishArtifact := false,
@@ -33,7 +38,17 @@ object GsPlugin extends AutoPlugin {
     },
     scalacOptions := {
       val prev = Keys.scalacOptions.value
-      prev ++ Gs.CompilerOptions
+      (prev ++ Gs.CompilerOptions).distinct
+    }
+  )
+
+  override lazy val buildSettings: Seq[Setting[_]] = Seq(
+    writeScalaVersionToFile := {
+      val outputFile = ScalaVersionFile
+      Files.write(
+        Paths.get(outputFile),
+        scalaVersion.value.getBytes(StandardCharsets.UTF_8)
+      )
     }
   )