Merge branch 'master' of github.com:lihaoyi/mill

3 files changed, 28 insertions, 4 deletions

diff --git a/build.sc b/build.sc
index 18cb0388..7ccb2d32 100755
--- a/build.sc
+++ b/build.sc
@@ -50,4 +50,8 @@ object ScalaPlugin extends ScalaModule {
   override def projectDeps = Seq(Core)
   def basePath = pwd / 'scalaplugin
   override def sources = pwd/'scalaplugin/'src/'main/'scala
+
+  override def prependShellScript =
+    "#!/usr/bin/env sh\n" +
+    "exec java -cp \"$0\" mill.scalaplugin.Main \"$@\""
 }
\ No newline at end of file
diff --git a/core/src/main/scala/mill/modules/Jvm.scala b/core/src/main/scala/mill/modules/Jvm.scala
index 84ae5c42..bccdfece 100644
--- a/core/src/main/scala/mill/modules/Jvm.scala
+++ b/core/src/main/scala/mill/modules/Jvm.scala
@@ -1,7 +1,7 @@
 package mill.modules
 
 import java.io.FileOutputStream
-import java.util.jar.{JarEntry, JarFile, JarInputStream, JarOutputStream}
+import java.util.jar.{JarEntry, JarFile, JarOutputStream}
 
 import ammonite.ops._
 import mill.define.Task
@@ -65,21 +65,32 @@ object Jvm {
 
   def createAssembly(outputPath: Path,
                      inputPaths: Seq[Path],
-                     mainClass: Option[String] = None): Option[Path] = {
+                     mainClass: Option[String] = None,
+                     prependShellScript: String = "\n"): Option[Path] = {
     rm(outputPath)
 
     if(inputPaths.isEmpty) None
     else {
       mkdir(outputPath/up)
 
+      val output = new FileOutputStream(outputPath.toIO)
+
+      // Prepend shell script
+      output.write((prependShellScript + "\n").getBytes)   
+      if (prependShellScript.nonEmpty) {
+        import ammonite.ops.ImplicitWd._
+        %%("chmod", "+x", outputPath)
+      }
+
       val jar = new JarOutputStream(
-        new FileOutputStream(outputPath.toIO),
+        output,
         createManifest(mainClass)
       )
 
       val seen = mutable.Set("META-INF/MANIFEST.MF")
       try{
         assert(inputPaths.forall(exists(_)))
+
         for{
           p <- inputPaths
 
@@ -106,6 +117,7 @@ object Jvm {
         }
       } finally {
         jar.close()
+        output.close()
       }
 
       Some(outputPath)
diff --git a/scalaplugin/src/main/scala/mill/scalaplugin/ScalaModule.scala b/scalaplugin/src/main/scala/mill/scalaplugin/ScalaModule.scala
index 5a1f261a..2e842a6e 100644
--- a/scalaplugin/src/main/scala/mill/scalaplugin/ScalaModule.scala
+++ b/scalaplugin/src/main/scala/mill/scalaplugin/ScalaModule.scala
@@ -159,6 +159,11 @@ object ScalaModule{
   def scalaRuntimeIvyDeps(scalaVersion: String) = Seq[Dep](
     Dep.Java("org.scala-lang", "scala-library", scalaVersion)
   )
+
+  val DefaultShellScript: Seq[String] = Seq(
+    "#!/usr/bin/env sh",
+    "exec java -jar \"$0\" \"$@\""
+  )
 }
 import ScalaModule._
 trait TestScalaModule extends ScalaModule with TaskModule{
@@ -247,6 +252,8 @@ trait ScalaModule extends Module{ outer =>
       )
   }
 
+  def prependShellScript: T[String] = T{ "" }
+
   def sources = T.source{ basePath / 'src }
   def resources = T.source{ basePath / 'resources }
   def compile = T.persistent{
@@ -256,7 +263,8 @@ trait ScalaModule extends Module{ outer =>
     val dest = T.ctx().dest
     createAssembly(
       dest,
-      (runDepClasspath().filter(_.path.ext != "pom") ++ Seq(resources(), compile())).map(_.path).filter(exists)
+      (runDepClasspath().filter(_.path.ext != "pom") ++ Seq(resources(), compile())).map(_.path).filter(exists),
+      prependShellScript = prependShellScript()
     )
     PathRef(dest)
   }