Minor refactorings to improve readability.

src/main/scala/ChainedAction.scala

@@ -0,0 +1,15 @@
+/* sbt Scalariform plugin
+ * Copyright 2010 Olivier Michallat
+ */
+package com.github.olim7t.sbtscalariform
+
+/** The sole purpose of this file is to rename Option's "orElse" method to "andThen".
+ * This is so much clearer when chaining functions that return Some[String] to indicate an error.
+ */
+object ChainedAction {
+	implicit def optionToChainedAction(o: Option[String]) = new ChainedAction(o)
+}
+
+class ChainedAction(lastResult: Option[String]) {
+	def andThen(nextAction: => Option[String]) = lastResult orElse nextAction
+}

src/main/scala/ScalariformPlugin.scala

@@ -9,42 +9,20 @@ import scala.io.Source
 import java.io.File
 import FileUtilities.{ Newline, write }
 import Actions._
+import ChainedAction._
 
 trait ScalariformPlugin extends BasicScalaProject with SourceTasks {
   import ScalariformPlugin._
 
-  // Find the Scalariform jar, which has been downloaded as a dependency of the plugin
-  private def sfClasspath: Option[String] = {
-    def pluginDeps(p: Project) = p.info.pluginsManagedDependencyPath
-    val projectSearchPath = pluginDeps(this)
-    // The plugin might be declared on the parent project
-    val parentSearchPath = info.parent.map(pluginDeps(_)) getOrElse Path.emptyPathFinder
-
-    val jarFinder = descendents(projectSearchPath +++ parentSearchPath, "scalariform*.jar")
-    val jars = jarFinder.get
-    if (jars.size > 1) log.warn("Multiple scalariform jars found: " + jars)
-    if (jars.size == 0)
-      None
-    else
-      Some(Path.makeString(jars))
-  }
-
-  private def sfScalaJars = {
-    val si = getScalaInstance(ScalaVersion)
-    si.libraryJar :: si.compilerJar :: Nil
-  }
-
   def scalariformOptions = Seq[ScalariformOption]()
   def scalariformTestOptions = scalariformOptions
-
   def scalaSourcesEncoding = "UTF-8"
+  def sourcesTimestamp = "sources.lastFormatted"
+  def testSourcesTimestamp = "testSources.lastFormatted"
 
   lazy val formatSources = formatSourcesAction
   lazy val testFormatSources = testFormatSourcesAction
 
-  def sourcesTimestamp = "sources.lastFormatted"
-  def testSourcesTimestamp = "testSources.lastFormatted"
-
   def formatSourcesAction = forAllSourcesTask(sourcesTimestamp from mainSources) { sources =>
     format(sources, scalariformOptions)
   } describedAs ("Format main Scala sources")
@@ -56,27 +34,52 @@ trait ScalariformPlugin extends BasicScalaProject with SourceTasks {
   override def compileAction = super.compileAction dependsOn (formatSources)
   override def testCompileAction = super.testCompileAction dependsOn (testFormatSources)
 
+  private val Scalariform = new ForkScala(ScalariformMainClass)
+  private val NoJavaHome = None
+
   private def format(sources: Iterable[Path], options: Seq[ScalariformOption]): Option[String] = sfClasspath match {
     case None => Some("Scalariform jar not found. Try running `;clean-plugins;reload`.")
     case Some(cp) =>
       def run(fileList: File): Option[String] = {
-        val fork = new ForkScala(ScalariformMainClass)
-        // Assume InPlace if neither InPlace nor Test are provided
-        val finalOpts = if ((options contains InPlace) || (options contains Test)) options else options ++ Seq(InPlace)
-        val args = finalOpts.map(_.asArgument)
+        val jvmOptions = Seq("-cp", cp, "-Dfile.encoding=" + scalaSourcesEncoding)
+        val finalOpts = completeWithDefaults(options)
+        val arguments = finalOpts.map(_.asArgument) ++ Seq("-l=" + fileList.getAbsolutePath)
+
         withSuccessCode(0, "Scalariform invocation failed") {
-          fork(None,
-            Seq("-cp", cp, "-Dfile.encoding=" + scalaSourcesEncoding),
-            sfScalaJars,
-            args ++ Seq("-l=" + fileList.getAbsolutePath),
-            log)
+          Scalariform(NoJavaHome, jvmOptions, sfScalaJars, arguments, log)
         }
       }
       withTemporaryFile(log, "sbt-scalariform", ".lst") { file =>
-        write(file, sources.map(_.absolutePath).mkString(Newline), log) orElse
-          run(file)
+        write(file, sources.map(_.absolutePath).mkString(Newline), log) andThen run(file)
       }
   }
+
+  // Find the Scalariform jar, which has been downloaded as a dependency of the plugin
+  private def sfClasspath: Option[String] = {
+    def pluginDeps(p: Project) = p.info.pluginsManagedDependencyPath
+    val projectSearchPath = pluginDeps(this)
+    // The plugin might be declared on the parent project
+    val parentSearchPath = info.parent.map(pluginDeps(_)) getOrElse Path.emptyPathFinder
+
+    val jarFinder = descendents(projectSearchPath +++ parentSearchPath, "scalariform*.jar")
+    val jars = jarFinder.get
+    if (jars.size > 1) log.warn("Multiple scalariform jars found: " + jars)
+    if (jars.size == 0)
+      None
+    else
+      Some(Path.makeString(jars))
+  }
+
+  private def sfScalaJars = {
+    val si = getScalaInstance(ScalaVersion)
+    si.libraryJar :: si.compilerJar :: Nil
+  }
+
+  private def completeWithDefaults(options: Seq[ScalariformOption]) =
+    if ((options contains InPlace) || (options contains Test))
+    	options
+    else
+    	options ++ Seq(InPlace)
 }
 object ScalariformPlugin {
   /** The version of Scala used to run Scalariform.*/

src/main/scala/SourceTask.scala

@@ -41,12 +41,12 @@ object SourceTasks {
     }
   }
   def processAll(label: String, files: TimestampSources, log: Logger)(globalAction: Iterable[Path] => Option[String]): Option[String] = {
+  	import ChainedAction._
     import files._
     val modified = sources.filter(_.lastModified > timestamp.lastModified)
     if (modified isEmpty)
       None
     else
-      globalAction(modified) orElse
-        FileUtilities.touch(timestamp, log)
+      globalAction(modified) andThen FileUtilities.touch(timestamp, log)
   }
 }