use File.pathSeparator for classpath in genDocs and dottydocs

- use File.pathSeparator instead of hard-coded path separator `:`
  => this way Windows user can run the command as well

Author: robstoll

project/Build.scala

@@ -345,7 +345,7 @@ object Build {
       javacOptions in (Compile, doc) --= Seq("-Xlint:unchecked", "-Xlint:deprecation")
     )
 
-  // Settings shared between dotty-doc and dotty-doc-bootstrapped
+    // Settings shared between dotty-doc and dotty-doc-bootstrapped
   lazy val dottyDocSettings = Seq(
     baseDirectory in (Compile, run) := baseDirectory.value / "..",
     baseDirectory in Test := baseDirectory.value / "..",
@@ -362,11 +362,12 @@ object Build {
       // Make majorVersion available at dotty.epfl.ch/versions/latest-nightly-base
       // Used by sbt-dotty to resolve the latest nightly
       val majorVersion = baseVersion.take(baseVersion.lastIndexOf('.'))
-      IO.write(file("./docs/_site/versions/latest-nightly-base"), majorVersion)
+      IO.write(file("./docs/_site/versions/latest-nightly-base"), majorVersion)     
 
       val dottyLib = (packageAll in `dotty-compiler`).value("dotty-library")
       val dottyInterfaces = (packageAll in `dotty-compiler`).value("dotty-interfaces")
-      val otherDeps = (dependencyClasspath in Compile).value.map(_.data).mkString(":")
+      val otherDeps = (dependencyClasspath in Compile).value.map(_.data).mkString(File.pathSeparator)
+      val docClasspath = dottyLib + File.pathSeparator + dottyInterfaces + File.pathSeparator + otherDeps     
       val sources =
         (unmanagedSources in (Compile, compile)).value ++
           (unmanagedSources in (`dotty-compiler`, Compile)).value
@@ -375,7 +376,7 @@ object Build {
         "-project", "Dotty",
         "-project-version", dottyVersion,
         "-project-url", dottyGithubUrl,
-        "-classpath", s"$dottyLib:$dottyInterfaces:$otherDeps"
+        "-classpath", docClasspath
       )
       (runMain in Compile).toTask(
         s""" dotty.tools.dottydoc.Main ${args.mkString(" ")} ${sources.mkString(" ")}"""
@@ -386,8 +387,9 @@ object Build {
       val args: Seq[String] = spaceDelimited("<arg>").parsed
       val dottyLib = (packageAll in `dotty-compiler`).value("dotty-library")
       val dottyInterfaces = (packageAll in `dotty-compiler`).value("dotty-interfaces")
-      val otherDeps = (dependencyClasspath in Compile).value.map(_.data).mkString(":")
-      val cp: Seq[String] = Seq("-classpath", s"$dottyLib:$dottyInterfaces:$otherDeps")
+      val otherDeps = (dependencyClasspath in Compile).value.map(_.data).mkString(File.pathSeparator)
+      val docClasspath = dottyLib + File.pathSeparator + dottyInterfaces + File.pathSeparator + otherDeps     
+      val cp: Seq[String] = Seq("-classpath", docClasspath)
         (runMain in Compile).toTask(s""" dotty.tools.dottydoc.Main ${cp.mkString(" ")} """ + args.mkString(" "))
     }.evaluated,