plugin runner now detects scala version for env var set by sbt

Author: sksamuel

build.sbt

@@ -39,10 +39,10 @@ crossScalaVersions := Seq("2.10.4", "2.11.0")
 libraryDependencies := {
   CrossVersion.partialVersion(scalaVersion.value) match {
     case Some((2, scalaMajor)) if scalaMajor == 11 =>
-      System.setProperty("CrossBuildScalaVersion", "2.11.0")
+      EnvSupport.setEnv("CrossBuildScalaVersion", "2.11.0")
       libraryDependencies.value :+ "org.scala-lang.modules" %% "scala-xml" % "1.0.1"
     case _ =>
-      System.setProperty("CrossBuildScalaVersion", "2.10.4")
+      EnvSupport.setEnv("CrossBuildScalaVersion", "2.10.4")
       libraryDependencies.value
   }
 }

project/EnvSupport.scala

@@ -0,0 +1,48 @@
+
+/** @author Stephen Samuel */
+object EnvSupport {
+
+  // code credit: http://stackoverflow.com/a/19040660/2048448
+  def setEnv(k: String, v: String): Unit = {
+    try {
+      val processEnvironmentClass = Class.forName("java.lang.ProcessEnvironment")
+      val theEnvironmentField = processEnvironmentClass.getDeclaredField("theEnvironment")
+      theEnvironmentField.setAccessible(true)
+
+      val variableClass = Class.forName("java.lang.ProcessEnvironment$Variable")
+      val convertToVariable = variableClass.getMethod("valueOf", classOf[java.lang.String])
+      convertToVariable.setAccessible(true)
+
+      val valueClass = Class.forName("java.lang.ProcessEnvironment$Value")
+      val convertToValue = valueClass.getMethod("valueOf", classOf[java.lang.String])
+      convertToValue.setAccessible(true)
+
+      val sampleVariable = convertToVariable.invoke(null, "")
+      val sampleValue = convertToValue.invoke(null, "")
+      val env = theEnvironmentField.get(null).asInstanceOf[java.util.Map[sampleVariable.type, sampleValue.type]]
+
+      val variable = convertToVariable.invoke(null, k).asInstanceOf[sampleVariable.type]
+      val value = convertToValue.invoke(null, v).asInstanceOf[sampleValue.type]
+      env.put(variable, value)
+
+      val theCaseInsensitiveEnvironmentField = processEnvironmentClass.getDeclaredField("theCaseInsensitiveEnvironment")
+      theCaseInsensitiveEnvironmentField.setAccessible(true)
+      val cienv = theCaseInsensitiveEnvironmentField.get(null).asInstanceOf[java.util.Map[String, String]]
+      cienv.put(k, v)
+
+    }
+    catch {
+      case e: NoSuchFieldException =>
+        val classes = classOf[java.util.Collections].getDeclaredClasses
+        val env = System.getenv()
+        classes foreach (cl => {
+          if ("java.util.Collections$UnmodifiableMap" == cl.getName) {
+            val field = cl.getDeclaredField("m")
+            field.setAccessible(true)
+            val map = field.get(env).asInstanceOf[java.util.Map[String, String]]
+            map.put(k, v)
+          }
+        })
+    }
+  }
+}

src/test/scala/scoverage/PluginRunner.scala

@@ -10,22 +10,20 @@ import scala.collection.mutable.ListBuffer
 /** @author Stephen Samuel */
 trait PluginSupport {
 
-  val scalaVersion = "2.11.0"
-  // System.getProperty("CrossBuildScalaVersion")
+  val scalaVersion = Option(System.getenv("CrossBuildScalaVersion")).getOrElse("2.11.0")
   val shortScalaVersion = scalaVersion.dropRight(2)
 
   val classPath = getScalaJars.map(_.getAbsolutePath) :+ sbtCompileDir.getAbsolutePath
 
   val settings = {
-    val settings = new scala.tools.nsc.Settings
-    settings.Xprint.value = List("all")
-    settings.Yrangepos.value = true
-    settings.classpath.value = classPath.mkString(":")
-    settings
+    val s = new scala.tools.nsc.Settings
+    s.Xprint.value = List("all")
+    s.Yrangepos.value = true
+    s.classpath.value = classPath.mkString(":")
+    s
   }
 
   val reporter = new scala.tools.nsc.reporters.ConsoleReporter(settings)
-
   val compiler = new ScoverageAwareCompiler(settings, reporter)
 
   def writeCodeSnippetToTempFile(code: String): File = {
@@ -83,6 +81,8 @@ trait PluginSupport {
   }
 }
 
+
+
 class ScoverageAwareCompiler(settings: scala.tools.nsc.Settings, reporter: scala.tools.nsc.reporters.Reporter)
   extends scala.tools.nsc.Global(settings, reporter) {