Address review

Author: OlivierBlanvillain

compiler/src/dotty/tools/backend/jvm/DottyBackendInterface.scala

@@ -76,7 +76,7 @@ class DottyBackendInterface(outputDirectory: AbstractFile, val superCallsMap: Ma
   type LabelDef        = tpd.DefDef
   type Closure         = tpd.Closure
 
-  val NoSymbol: Symbols.NoSymbol.type = Symbols.NoSymbol
+  val NoSymbol: Symbol = Symbols.NoSymbol
   val NoPosition: Position = Positions.NoPosition
   val EmptyTree: Tree = tpd.EmptyTree
 

compiler/src/dotty/tools/backend/jvm/GenBCode.scala

@@ -32,7 +32,7 @@ import dotty.tools.io._
 class GenBCode extends Phase {
   def phaseName: String = GenBCode.name
   private val entryPoints = new mutable.HashSet[Symbol]()
-  def registerEntryPoint(sym: Symbol): mutable.HashSet[Symbol] = entryPoints += sym
+  def registerEntryPoint(sym: Symbol): Unit = entryPoints += sym
 
   private val superCallsMap = newMutableSymbolMap[Set[ClassSymbol]]
   def registerSuperCall(sym: Symbol, calls: ClassSymbol): Unit = {
@@ -70,9 +70,9 @@ object GenBCode {
 
 class GenBCodePipeline(val entryPoints: List[Symbol], val int: DottyBackendInterface)(implicit val ctx: Context) extends BCodeSyncAndTry {
 
-  var tree: Tree = _
+  private[this] var tree: Tree = _
 
-  val sourceFile: SourceFile = ctx.compilationUnit.source
+  private[this] val sourceFile: SourceFile = ctx.compilationUnit.source
 
   /** Convert a `dotty.tools.io.AbstractFile` into a
    *  `dotty.tools.dotc.interfaces.AbstractFile`.

compiler/src/dotty/tools/dotc/ast/Desugar.scala

@@ -609,7 +609,7 @@ object desugar {
       else cpy.ValDef(self)(tpt = selfType).withMods(self.mods | SelfName)
     }
 
-    val cdef1: DefTree = addEnumFlags {
+    val cdef1 = addEnumFlags {
       val originalTparamsIt = impliedTparams.toIterator
       val originalVparamsIt = originalVparamss.toIterator.flatten
       val tparamAccessors = derivedTparams.map(_.withMods(originalTparamsIt.next().mods))

compiler/src/dotty/tools/dotc/ast/DesugarEnums.scala

@@ -20,7 +20,7 @@ object DesugarEnums {
   }
 
   /** Attachment containing the number of enum cases and the smallest kind that was seen so far. */
-  val EnumCaseCount: Property.Key[(Int, DesugarEnums.CaseKind.Value)] = new Property.Key[(Int, CaseKind.Value)]
+  val EnumCaseCount: Property.Key[(Int, DesugarEnums.CaseKind.Value)] = new Property.Key
 
   /** The enumeration class that belongs to an enum case. This works no matter
    *  whether the case is still in the enum class or it has been transferred to the
@@ -68,7 +68,7 @@ object DesugarEnums {
     if (enumClass.exists) TypeTree(enumClass.typeRef) else TypeTree()
 
   /** Add implied flags to an enum class or an enum case */
-  def addEnumFlags(cdef: TypeDef)(implicit ctx: Context): cdef.ThisTree[Untyped] =
+  def addEnumFlags(cdef: TypeDef)(implicit ctx: Context): TypeDef =
     if (cdef.mods.isEnumClass) cdef.withMods(cdef.mods.withFlags(cdef.mods.flags | Abstract | Sealed))
     else if (isEnumCase(cdef)) cdef.withMods(cdef.mods.withFlags(cdef.mods.flags | Final))
     else cdef

compiler/src/dotty/tools/dotc/ast/Trees.scala

@@ -28,7 +28,7 @@ object Trees {
   @sharable var ntrees: Int = 0
 
   /** Property key for trees with documentation strings attached */
-  val DocComment: Property.StickyKey[Comments.Comment] = new Property.StickyKey[Comment]
+  val DocComment: Property.StickyKey[Comments.Comment] = new Property.StickyKey
 
   @sharable private[this] var nextId = 0 // for debugging
 

compiler/src/dotty/tools/dotc/ast/untpd.scala

@@ -36,7 +36,7 @@ object untpd extends Trees.Instance[Untyped] with UntypedTreeInfo {
   case class ModuleDef(name: TermName, impl: Template)
     extends MemberDef {
     type ThisTree[-T >: Untyped] <: Trees.NameTree[T] with Trees.MemberDef[T] with ModuleDef
-    def withName(name: Name)(implicit ctx: Context): untpd.ModuleDef = cpy.ModuleDef(this)(name.toTermName, impl)
+    def withName(name: Name)(implicit ctx: Context): ModuleDef = cpy.ModuleDef(this)(name.toTermName, impl)
   }
 
   case class ParsedTry(expr: Tree, handler: Tree, finalizer: Tree) extends TermTree
@@ -157,7 +157,7 @@ object untpd extends Trees.Instance[Untyped] with UntypedTreeInfo {
     def toTypeFlags: Modifiers = withFlags(flags.toTypeFlags)
     def toTermFlags: Modifiers = withFlags(flags.toTermFlags)
 
-    def withFlags(flags: FlagSet): untpd.Modifiers =
+    def withFlags(flags: FlagSet): Modifiers =
       if (this.flags == flags) this
       else copy(flags = flags)
 
@@ -188,7 +188,7 @@ object untpd extends Trees.Instance[Untyped] with UntypedTreeInfo {
       if (annots eq annotations) this
       else copy(annotations = annots)
 
-    def withPrivateWithin(pw: TypeName): untpd.Modifiers =
+    def withPrivateWithin(pw: TypeName): Modifiers =
       if (pw.isEmpty) this
       else copy(privateWithin = pw)
 
@@ -243,13 +243,13 @@ object untpd extends Trees.Instance[Untyped] with UntypedTreeInfo {
    *  from the symbol in this type. These type trees have marker trees
    *  TypeRefOfSym or InfoOfSym as their originals.
    */
-  val References: Property.Key[List[DerivedTypeTree]] = new Property.Key[List[DerivedTypeTree]]
+  val References: Property.Key[List[DerivedTypeTree]] = new Property.Key
 
   /** Property key for TypeTrees marked with TypeRefOfSym or InfoOfSym
    *  which contains the symbol of the original tree from which this
    *  TypeTree is derived.
    */
-  val OriginalSymbol: Property.Key[Symbol] = new Property.Key[Symbol]
+  val OriginalSymbol: Property.Key[Symbol] = new Property.Key
 
   // ------ Creation methods for untyped only -----------------
 
@@ -296,7 +296,7 @@ object untpd extends Trees.Instance[Untyped] with UntypedTreeInfo {
   def DefDef(name: TermName, tparams: List[TypeDef], vparamss: List[List[ValDef]], tpt: Tree, rhs: LazyTree): DefDef = new DefDef(name, tparams, vparamss, tpt, rhs)
   def TypeDef(name: TypeName, rhs: Tree): TypeDef = new TypeDef(name, rhs)
   def Template(constr: DefDef, parents: List[Tree], self: ValDef, body: LazyTreeList): Template = new Template(constr, parents, self, body)
-  def Import(expr: Tree, selectors: List[untpd.Tree]): Import = new Import(expr, selectors)
+  def Import(expr: Tree, selectors: List[Tree]): Import = new Import(expr, selectors)
   def PackageDef(pid: RefTree, stats: List[Tree]): PackageDef = new PackageDef(pid, stats)
   def Annotated(arg: Tree, annot: Tree): Annotated = new Annotated(arg, annot)
 
@@ -397,7 +397,7 @@ object untpd extends Trees.Instance[Untyped] with UntypedTreeInfo {
   abstract class ModsDecorator { def mods: Modifiers }
 
   implicit class modsDeco(val mdef: MemberDef)(implicit ctx: Context) {
-    def mods: untpd.Modifiers = mdef.rawMods
+    def mods: Modifiers = mdef.rawMods
   }
 
 // --------- Copier/Transformer/Accumulator classes for untyped trees -----
@@ -416,7 +416,7 @@ object untpd extends Trees.Instance[Untyped] with UntypedTreeInfo {
       }
     }.asInstanceOf[copied.ThisTree[Untyped]]
 
-    def ModuleDef(tree: Tree)(name: TermName, impl: Template): untpd.ModuleDef = tree match {
+    def ModuleDef(tree: Tree)(name: TermName, impl: Template): ModuleDef = tree match {
       case tree: ModuleDef if (name eq tree.name) && (impl eq tree.impl) => tree
       case _ => finalize(tree, untpd.ModuleDef(name, impl))
     }

compiler/src/dotty/tools/dotc/config/PathResolver.scala

@@ -223,7 +223,7 @@ class PathResolver(implicit ctx: Context) {
 
     // Assemble the elements!
     // priority class path takes precedence
-    def basis: List[Traversable[ClassPath]] = List[Traversable[ClassPath]](
+    def basis: List[Traversable[ClassPath]] = List(
       classesInExpandedPath(priorityClassPath),     // 0. The priority class path (for testing).
       JrtClassPath.apply(),                         // 1. The Java 9 classpath (backed by the jrt:/ virtual system, if available)
       classesInPath(javaBootClassPath),             // 2. The Java bootstrap class path.

compiler/src/dotty/tools/dotc/config/Properties.scala

@@ -14,7 +14,7 @@ object Properties extends PropertiesTrait {
 
   /** Scala manifest attributes.
    */
-  @sharable val ScalaCompilerVersion: java.util.jar.Attributes.Name = new AttributeName("Scala-Compiler-Version")
+  @sharable val ScalaCompilerVersion: AttributeName = new AttributeName("Scala-Compiler-Version")
 }
 
 trait PropertiesTrait {

compiler/src/dotty/tools/dotc/config/Settings.scala

@@ -16,13 +16,13 @@ import language.existentials
 
 object Settings {
 
-  val BooleanTag: ClassTag[Boolean] = ClassTag.Boolean
-  val IntTag: ClassTag[Int] = ClassTag.Int
-  val StringTag: ClassTag[Nothing] = ClassTag(classOf[String])
-  val ListTag: ClassTag[Nothing] = ClassTag(classOf[List[_]])
-  val VersionTag: ClassTag[Nothing] = ClassTag(classOf[ScalaVersion])
-  val OptionTag: ClassTag[Nothing] = ClassTag(classOf[Option[_]])
-  val OutputTag: ClassTag[Nothing] = ClassTag(classOf[AbstractFile])
+  val BooleanTag: ClassTag[Boolean]      = ClassTag.Boolean
+  val IntTag: ClassTag[Int]              = ClassTag.Int
+  val StringTag: ClassTag[String]        = ClassTag(classOf[String])
+  val ListTag: ClassTag[List[_]]         = ClassTag(classOf[List[_]])
+  val VersionTag: ClassTag[ScalaVersion] = ClassTag(classOf[ScalaVersion])
+  val OptionTag: ClassTag[Option[_]]     = ClassTag(classOf[Option[_]])
+  val OutputTag: ClassTag[AbstractFile]  = ClassTag(classOf[AbstractFile])
 
   class SettingsState(initialValues: Seq[Any]) {
     private[this] var values = ArrayBuffer(initialValues: _*)
@@ -193,12 +193,12 @@ object Settings {
 
   class SettingGroup {
 
-    val _allSettings: ArrayBuffer[Setting[T1] forSome { type T1 }] = new ArrayBuffer[Setting[_]]
+    private[this] val _allSettings: ArrayBuffer[Setting[_]] = new ArrayBuffer[Setting[_]]
     def allSettings: Seq[Setting[_]] = _allSettings
 
     def defaultState: SettingsState = new SettingsState(allSettings map (_.default))
 
-    def userSetSettings(state: SettingsState): Seq[Setting[T1] forSome { type T1 }] =
+    def userSetSettings(state: SettingsState): Seq[Setting[_]] =
       allSettings filterNot (_.isDefaultIn(state))
 
     def toConciseString(state: SettingsState): String =

compiler/src/dotty/tools/dotc/core/Annotations.scala

@@ -65,7 +65,7 @@ object Annotations {
     override def symbol(implicit ctx: Context): ClassSymbol = defn.BodyAnnot
     override def derivedAnnotation(tree: Tree)(implicit ctx: Context): Annotation =
       if (tree eq this.tree) this else ConcreteBodyAnnotation(tree)
-    override def arguments(implicit ctx: Context): Nil.type = Nil
+    override def arguments(implicit ctx: Context): List[Tree] = Nil
     override def ensureCompleted(implicit ctx: Context): Unit = ()
   }
 
@@ -90,7 +90,7 @@ object Annotations {
 
   object Annotation {
 
-    def apply(tree: Tree): Annotations.ConcreteAnnotation = ConcreteAnnotation(tree)
+    def apply(tree: Tree): ConcreteAnnotation = ConcreteAnnotation(tree)
 
     def apply(cls: ClassSymbol)(implicit ctx: Context): Annotation =
       apply(cls, Nil)

compiler/src/dotty/tools/dotc/core/Contexts.scala

@@ -81,7 +81,7 @@ object Contexts {
     val base: ContextBase
 
     /** All outer contexts, ending in `base.initialCtx` and then `NoContext` */
-    def outersIterator: AnyRef with Iterator[Context] { var current: Context;  } = new Iterator[Context] {
+    def outersIterator: Iterator[Context] = new Iterator[Context] {
       var current = thiscontext
       def hasNext = current != NoContext
       def next = { val c = current; current = current.outer; c }
@@ -523,7 +523,7 @@ object Contexts {
     def setSetting[T](setting: Setting[T], value: T): this.type =
       setSettings(setting.updateIn(settingsState, value))
 
-    def setDebug: FreshContext = setSetting(base.settings.Ydebug, true)
+    def setDebug: this.type = setSetting(base.settings.Ydebug, true)
   }
 
   implicit class ModeChanges(val c: Context) extends AnyVal {
@@ -666,7 +666,7 @@ object Contexts {
      *  instead of storing message computations directly in ErrorTypes in order
      *  to avoid space leaks - the message computation usually captures a context.
      */
-    private[core] val errorTypeMsg: mutable.Map[Types.ErrorType, () => Message] = mutable.Map[ErrorType, () => Message]()
+    private[core] val errorTypeMsg: mutable.Map[Types.ErrorType, () => Message] = mutable.Map()
 
     // Phases state
 
@@ -716,6 +716,6 @@ object Contexts {
   }
 
   @sharable object EmptyGADTMap extends GADTMap(SimpleIdentityMap.Empty) {
-    override def setBounds(sym: Symbol, b: TypeBounds): Nothing = unsupported("EmptyGADTMap.setBounds")
+    override def setBounds(sym: Symbol, b: TypeBounds): Unit = unsupported("EmptyGADTMap.setBounds")
   }
 }