Dotty plugin and example project.

1 files changed, 107 insertions, 0 deletions

diff --git a/stage2/plugins/Dotty.scala b/stage2/plugins/Dotty.scala
new file mode 100644
index 0000000..1e5addb
--- /dev/null
+++ b/stage2/plugins/Dotty.scala
@@ -0,0 +1,107 @@
+package cbt
+import java.io.File
+import java.net.URL
+import java.nio.file.Files
+import java.nio.file.attribute.FileTime
+
+trait Dotty extends BaseBuild{
+  override def scalacOptions: Seq[String] = Seq()
+
+  private object compileCache extends Cache[Option[File]]
+  override def compile: Option[File] = compileCache{
+    new DottyLib(logger).compile(
+      context.cbtHasChanged,
+      needsUpdate || context.parentBuild.map(_.needsUpdate).getOrElse(false),
+      sourceFiles, compileTarget, compileStatusFile, dependencyClasspath ++ compileClasspath,
+      context.paths.mavenCache, scalacOptions, context.classLoaderCache
+    )
+  }
+}
+
+class DottyLib(logger: Logger){
+  val lib = new Lib(logger)
+  import lib._
+
+  def compile(
+    cbtHasChanged: Boolean,
+    needsRecompile: Boolean,
+    files: Seq[File],
+    compileTarget: File,
+    statusFile: File,
+    classpath: ClassPath,
+    mavenCache: File,
+    scalacOptions: Seq[String] = Seq(),
+    classLoaderCache: ClassLoaderCache
+  ): Option[File] = {
+
+    if(classpath.files.isEmpty)
+      throw new Exception("Trying to compile with empty classpath. Source files: " ++ files.toString)
+
+    if( files.isEmpty ){
+      None
+    }else{
+      if( needsRecompile ){
+        def Resolver(urls: URL*) = MavenResolver(cbtHasChanged, mavenCache, urls: _*)
+        val dotty = Resolver(mavenCentral).bindOne(
+          MavenDependency("ch.epfl.lamp","dotty_2.11","0.1-20160925-b2b475d-NIGHTLY")
+        )
+
+        val cp = classpath ++ dotty.classpath
+        
+        val start = System.currentTimeMillis
+
+        val _class = "dotty.tools.dotc.Main"
+        val dualArgs =
+          Seq(
+            "-d", compileTarget.toString
+          )
+        val singleArgs = scalacOptions.map( "-S" ++ _ )
+
+        val code = 
+          try{
+            System.err.println("Compiling with Dotty to " ++ compileTarget.toString)
+            compileTarget.mkdirs
+            redirectOutToErr{
+              lib.runMain(
+                _class,
+                dualArgs ++ singleArgs ++ Seq(
+                  "-classpath", cp.string // let's put cp last. It so long
+                ) ++ files.map(_.toString),
+                dotty.classLoader(classLoaderCache)
+              )
+            }
+          } catch {
+            case e: Exception =>
+            System.err.println(red("Dotty crashed. Try running it by hand:"))
+            System.out.println(s"""
+java -cp \\
+${dotty.classpath.strings.mkString(":\\\n")} \\
+\\
+${_class} \\
+\\
+${dualArgs.grouped(2).map(_.mkString(" ")).mkString(" \\\n")} \\
+\\
+${singleArgs.mkString(" \\\n")} \\
+\\
+-classpath \\
+${cp.strings.mkString(":\\\n")} \\
+\\
+${files.sorted.mkString(" \\\n")}
+"""
+            )
+            ExitCode.Failure
+          }
+
+        if(code == ExitCode.Success){
+          // write version and when last compilation started so we can trigger
+          // recompile if cbt version changed or newer source files are seen
+          write(statusFile, "")//cbtVersion.getBytes)
+          Files.setLastModifiedTime(statusFile.toPath, FileTime.fromMillis(start) )
+        } else {
+          System.exit(code.integer) // FIXME: let's find a better solution for error handling. Maybe a monad after all.
+        }
+      }
+      Some( compileTarget )
+    }
+  }
+}