Simplify DottyPlugin.dottyPatchIncOptions

Author: allanrenucci

sbt-dotty/src/dotty/tools/sbtplugin/DottyPlugin.scala

@@ -112,14 +112,14 @@ object DottyPlugin extends AutoPlugin {
    *  corresponding .tasty or .hasTasty file is also deleted.
    */
   def dottyPatchIncOptions(incOptions: IncOptions): IncOptions = {
-    val inheritedNewClassFileManager = ClassFileManagerUtil.getDefaultClassFileManager(incOptions)
     val tastyFileManager = new ClassFileManager {
-      private[this] val inherited = inheritedNewClassFileManager
+      private[this] val inherited =
+        ClassFileManagerUtil.getDefaultClassFileManager(incOptions)
 
       def delete(classes: Array[File]): Unit = {
         val tastySuffixes = List(".tasty", ".hasTasty")
-        inherited.delete(classes flatMap { classFile =>
-          if (classFile.getPath endsWith ".class") {
+        inherited.delete(classes.flatMap { classFile =>
+          if (classFile.getPath.endsWith(".class")) {
             val prefix = classFile.getAbsolutePath.stripSuffix(".class")
             tastySuffixes.map(suffix => new File(prefix + suffix)).filter(_.exists)
           } else Nil
@@ -129,16 +129,10 @@ object DottyPlugin extends AutoPlugin {
       def generated(classes: Array[File]): Unit = {}
       def complete(success: Boolean): Unit = {}
     }
-    val inheritedHooks = incOptions.externalHooks
-    val externalClassFileManager: Optional[ClassFileManager] = Option(inheritedHooks.getExternalClassFileManager.orElse(null)) match {
-        case Some(prevManager) =>
-          Optional.of(WrappedClassFileManager.of(prevManager, Optional.of(tastyFileManager)))
-        case None =>
-          Optional.of(tastyFileManager)
-      }
 
-    val hooks = new DefaultExternalHooks(inheritedHooks.getExternalLookup, externalClassFileManager)
-    incOptions.withExternalHooks(hooks)
+    val newExternalHooks =
+      incOptions.externalHooks.withExternalClassFileManager(tastyFileManager)
+    incOptions.withExternalHooks(newExternalHooks)
   }
 
   override val globalSettings: Seq[Def.Setting[_]] = Seq(