Merge pull request #9407 from dotty-staging/use-extension-methods

Use extension methods

Author: nicolasstucki

compiler/src/dotty/tools/dotc/CompilationUnit.scala

@@ -12,7 +12,7 @@ import tpd.{Tree, TreeTraverser}
 import typer.PrepareInlineable.InlineAccessors
 import typer.Nullables
 import transform.SymUtils._
-import core.Decorators.{given _}
+import core.Decorators._
 import config.SourceVersion
 
 class CompilationUnit protected (val source: SourceFile) {

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

@@ -5,7 +5,7 @@ package ast
 import core._
 import util.Spans._, Types._, Contexts._, Constants._, Names._, NameOps._, Flags._
 import Symbols._, StdNames._, Trees._, Phases._, ContextOps._
-import Decorators.{given _}, transform.SymUtils._
+import Decorators._, transform.SymUtils._
 import NameKinds.{UniqueName, EvidenceParamName, DefaultGetterName}
 import typer.{FrontEnd, Namer}
 import util.{Property, SourceFile, SourcePosition}

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

@@ -831,7 +831,7 @@ trait TypedTreeInfo extends TreeInfo[Type] { self: Trees.Instance[Type] =>
   /** Structural tree comparison (since == on trees is reference equality).
    *  For the moment, only Ident, Select, Literal, Apply and TypeApply are supported
    */
-  implicit class StructuralEqDeco(t1: Tree) {
+  extension (t1: Tree) {
     def === (t2: Tree)(using Context): Boolean = (t1, t2) match {
       case (t1: Ident, t2: Ident) =>
         t1.symbol == t2.symbol

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

@@ -9,7 +9,7 @@ import transform.TypeUtils._
 import core._
 import util.Spans._, Types._, Contexts._, Constants._, Names._, Flags._, NameOps._
 import Symbols._, StdNames._, Annotations._, Trees._, Symbols._
-import Decorators.{given _}, DenotTransformers._
+import Decorators._, DenotTransformers._
 import collection.{immutable, mutable}
 import util.{Property, SourceFile, NoSource}
 import NameKinds.{TempResultName, OuterSelectName}
@@ -1111,12 +1111,11 @@ object tpd extends Trees.Instance[Type] with TypedTreeInfo {
       !(sym.is(Method) && sym.info.isInstanceOf[MethodOrPoly]) // if is a method it is parameterless
   }
 
-  implicit class ListOfTreeDecorator(val xs: List[tpd.Tree]) extends AnyVal {
+  extension (xs: List[tpd.Tree]):
     def tpes: List[Type] = xs match {
       case x :: xs1 => x.tpe :: xs1.tpes
       case nil => Nil
     }
-  }
 
   /** A trait for loaders that compute trees. Currently implemented just by DottyUnpickler. */
   trait TreeProvider {

compiler/src/dotty/tools/dotc/classpath/ClassPathFactory.scala

@@ -4,7 +4,7 @@
 package dotty.tools.dotc.classpath
 
 import dotty.tools.io.{AbstractFile, VirtualDirectory}
-import FileUtils.AbstractFileOps
+import FileUtils._
 import dotty.tools.io.ClassPath
 import dotty.tools.dotc.core.Contexts._
 

compiler/src/dotty/tools/dotc/classpath/FileUtils.scala

@@ -12,7 +12,7 @@ import dotty.tools.io.AbstractFile
  * Common methods related to Java files and abstract files used in the context of classpath
  */
 object FileUtils {
-  implicit class AbstractFileOps(val file: AbstractFile) extends AnyVal {
+  extension (file: AbstractFile) {
     def isPackage: Boolean = file.isDirectory && mayBeValidPackage(file.name)
 
     def isClass: Boolean = !file.isDirectory && file.hasExtension("class") && !file.name.endsWith("$class.class")
@@ -30,7 +30,7 @@ object FileUtils {
     def toURLs(default: => Seq[URL] = Seq.empty): Seq[URL] = if (file.file == null) default else Seq(file.toURL)
   }
 
-  implicit class FileOps(val file: JFile) extends AnyVal {
+  extension (file: JFile) {
     def isPackage: Boolean = file.isDirectory && mayBeValidPackage(file.getName)
 
     def isClass: Boolean = file.isFile && file.getName.endsWith(".class") && !file.getName.endsWith("$class.class")

compiler/src/dotty/tools/dotc/classpath/ZipArchiveFileLookup.scala

@@ -7,7 +7,7 @@ import java.io.File
 import java.net.URL
 
 import dotty.tools.io.{ AbstractFile, FileZipArchive }
-import FileUtils.AbstractFileOps
+import FileUtils._
 import dotty.tools.io.{ClassPath, ClassRepresentation}
 
 /**

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

@@ -184,7 +184,7 @@ object Settings {
   }
 
   object Setting {
-    implicit class SettingDecorator[T](val setting: Setting[T]) extends AnyVal {
+    extension [T](setting: Setting[T]) {
       def value(using Context): T = setting.valueIn(ctx.settingsState)
       def update(x: T)(using Context): SettingsState = setting.updateIn(ctx.settingsState, x)
       def isDefault(using Context): Boolean = setting.isDefaultIn(ctx.settingsState)

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

@@ -678,15 +678,15 @@ object Contexts {
   end ops
 
   // TODO: Fix issue when converting ModeChanges and FreshModeChanges to extension givens
-  implicit class ModeChanges(val c: Context) extends AnyVal {
+  extension (c: Context) {
     final def withModeBits(mode: Mode): Context =
       if (mode != c.mode) c.fresh.setMode(mode) else c
 
     final def addMode(mode: Mode): Context = withModeBits(c.mode | mode)
     final def retractMode(mode: Mode): Context = withModeBits(c.mode &~ mode)
   }
 
-  implicit class FreshModeChanges(val c: FreshContext) extends AnyVal {
+  extension (c: FreshContext) {
     final def addMode(mode: Mode): c.type = c.setMode(c.mode | mode)
     final def retractMode(mode: Mode): c.type = c.setMode(c.mode &~ mode)
   }

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

@@ -28,28 +28,26 @@ object Decorators {
       case s: String => termName(s)
       case n: Name => n.toTermName
 
-  implicit class StringDecorator(val s: String) extends AnyVal {
+  extension (s: String):
     def splitWhere(f: Char => Boolean, doDropIndex: Boolean): Option[(String, String)] = {
       def splitAt(idx: Int, doDropIndex: Boolean): Option[(String, String)] =
         if (idx == -1) None
         else Some((s.take(idx), s.drop(if (doDropIndex) idx + 1 else idx)))
 
       splitAt(s.indexWhere(f), doDropIndex)
     }
-  }
 
   /** Implements a findSymbol method on iterators of Symbols that
    *  works like find but avoids Option, replacing None with NoSymbol.
    */
-  implicit class SymbolIteratorDecorator(val it: Iterator[Symbol]) extends AnyVal {
+  extension (it: Iterator[Symbol]):
     final def findSymbol(p: Symbol => Boolean): Symbol = {
       while (it.hasNext) {
         val sym = it.next()
         if (p(sym)) return sym
       }
       NoSymbol
     }
-  }
 
   final val MaxFilterRecursions = 1000
 
@@ -161,29 +159,27 @@ object Decorators {
     def & (ys: List[T]): List[T] = xs filter (ys contains _)
   }
 
-  given ListOfListDecorator as AnyRef:
-    extension [T, U](xss: List[List[T]]):
-      def nestedMap(f: T => U): List[List[U]] =
-        xss.map(_.map(f))
-      def nestedMapConserve(f: T => U): List[List[U]] =
-        xss.mapconserve(_.mapconserve(f))
-      def nestedZipWithConserve(yss: List[List[U]])(f: (T, U) => T): List[List[T]] =
-        xss.zipWithConserve(yss)((xs, ys) => xs.zipWithConserve(ys)(f))
-    end extension
-
-  implicit class TextToString(val text: Text) extends AnyVal {
+  extension [T, U](xss: List[List[T]]):
+    def nestedMap(f: T => U): List[List[U]] =
+      xss.map(_.map(f))
+    def nestedMapConserve(f: T => U): List[List[U]] =
+      xss.mapconserve(_.mapconserve(f))
+    def nestedZipWithConserve(yss: List[List[U]])(f: (T, U) => T): List[List[T]] =
+      xss.zipWithConserve(yss)((xs, ys) => xs.zipWithConserve(ys)(f))
+  end extension
+
+  extension (text: Text):
     def show(using Context): String = text.mkString(ctx.settings.pageWidth.value, ctx.settings.printLines.value)
-  }
 
   /** Test whether a list of strings representing phases contains
    *  a given phase. See [[config.CompilerCommand#explainAdvanced]] for the
    *  exact meaning of "contains" here.
    */
-  implicit class PhaseListDecorator(val names: List[String]) extends AnyVal {
+   extension (names: List[String]) {
     def containsPhase(phase: Phase): Boolean =
       names.nonEmpty && {
         phase match {
-          case phase: MegaPhase => phase.miniPhases.exists(containsPhase)
+          case phase: MegaPhase => phase.miniPhases.exists(x => names.containsPhase(x))
           case _ =>
             names exists { name =>
               name == "all" || {
@@ -197,7 +193,7 @@ object Decorators {
       }
   }
 
-  implicit class reportDeco[T](x: T) extends AnyVal {
+  extension [T](x: T) {
     def reporting(
         op: WrappedResult[T] ?=> String,
         printer: config.Printers.Printer = config.Printers.default): T = {
@@ -206,7 +202,7 @@ object Decorators {
     }
   }
 
-  implicit class genericDeco[T](val x: T) extends AnyVal {
+  extension [T](x: T) {
     def assertingErrorsReported(using Context): T = {
       assert(ctx.reporter.errorsReported)
       x
@@ -217,7 +213,7 @@ object Decorators {
     }
   }
 
-  implicit class StringInterpolators(val sc: StringContext) extends AnyVal {
+  extension (sc: StringContext) {
     /** General purpose string formatting */
     def i(args: Any*)(using Context): String =
       new StringFormatter(sc).assemble(args)
@@ -235,8 +231,8 @@ object Decorators {
       explained(em(args: _*))
   }
 
-  implicit class ArrayInterpolator[T <: AnyRef](val arr: Array[T]) extends AnyVal {
+  extension [T <: AnyRef](arr: Array[T]):
     def binarySearch(x: T): Int = java.util.Arrays.binarySearch(arr.asInstanceOf[Array[Object]], x)
-  }
+
 }
 

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

@@ -7,6 +7,7 @@ import Names._, StdNames._, Contexts._, Symbols._, Flags._, NameKinds._, Types._
 import scala.internal.Chars
 import Chars.isOperatorPart
 import Definitions._
+import nme._
 
 object NameOps {
 
@@ -49,8 +50,7 @@ object NameOps {
     }
   }
 
-  implicit class NameDecorator[N <: Name](private val name: N) extends AnyVal {
-    import nme._
+  extension [N <: Name](name: N) {
 
     def testSimple(f: SimpleName => Boolean): Boolean = name match {
       case name: SimpleName => f(name)
@@ -268,8 +268,7 @@ object NameOps {
     }
   }
 
-  implicit class TermNameDecorator(private val name: TermName) extends AnyVal {
-    import nme._
+  extension (name: TermName) {
 
     def setterName: TermName = name.exclude(FieldName) ++ str.SETTER_SUFFIX
 

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

@@ -7,7 +7,7 @@ import dotty.tools.dotc.core.Types._
 /** Defines operations on nullable types. */
 object NullOpsDecorator {
 
-  implicit class NullOps(val self: Type) {
+  extension (self: Type) {
     /** Is this type exactly `UncheckedNull` (no vars, aliases, refinements etc allowed)? */
     def isUncheckedNullType(using Context): Boolean = {
       assert(ctx.explicitNulls)

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

@@ -10,7 +10,7 @@ import Constants.Constant
 import TypeApplications.TypeParamInfo
 import Scopes.Scope
 import dotty.tools.io.AbstractFile
-import Decorators.SymbolIteratorDecorator
+import Decorators._
 import ast._
 import ast.Trees.{LambdaTypeTree, TypeBoundsTree, ValDef, TypeDef}
 import Trees.Literal

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

@@ -9,7 +9,7 @@ import config.Config
 import Contexts._, Symbols._, Flags._, SymDenotations._, Types._, Scopes._, Names._
 import NameOps._
 import StdNames.str
-import Decorators.StringInterpolators
+import Decorators._
 import classfile.ClassfileParser
 import util.Stats
 import Decorators._

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

@@ -454,7 +454,7 @@ object Symbols {
 
   NoDenotation // force it in order to set `denot` field of NoSymbol
 
-  implicit class Copier[N <: Name](sym: Symbol { type ThisName = N })(using Context) {
+  extension [N <: Name](sym: Symbol { type ThisName = N })(using Context) {
     /** Copy a symbol, overriding selective fields.
      *  Note that `coord` and `associatedFile` will be set from the fields in `owner`, not
      *  the fields in `sym`.

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

@@ -22,7 +22,7 @@ import scala.util.control.NonFatal
 import typer.ProtoTypes.constrained
 import typer.Applications.productSelectorTypes
 import reporting.trace
-import NullOpsDecorator.NullOps
+import NullOpsDecorator._
 
 /** Provides methods to compare types.
  */

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

@@ -5650,7 +5650,7 @@ object Types {
 
   implicit def decorateTypeApplications(tpe: Type): TypeApplications = new TypeApplications(tpe)
 
-  implicit class typeListDeco(val tps1: List[Type]) extends AnyVal {
+  extension (tps1: List[Type]) {
     @tailrec def hashIsStable: Boolean =
       tps1.isEmpty || tps1.head.hashIsStable && tps1.tail.hashIsStable
     @tailrec def equalElements(tps2: List[Type], bs: BinderPairs): Boolean =

compiler/src/dotty/tools/dotc/core/tasty/TreeUnpickler.scala

@@ -27,7 +27,7 @@ import util.Spans._
 import util.SourceFile
 import ast.{TreeTypeMap, Trees, tpd, untpd}
 import Trees._
-import Decorators.{given _}
+import Decorators._
 import transform.SymUtils._
 
 import dotty.tools.tasty.{TastyBuffer, TastyReader}

compiler/src/dotty/tools/dotc/core/unpickleScala2/Scala2Unpickler.scala

@@ -596,9 +596,9 @@ class Scala2Unpickler(bytes: Array[Byte], classRoot: ClassDenotation, moduleClas
               else tp1
             if (denot.isConstructor) addConstructorTypeParams(denot)
             if (atEnd)
-              assert(!denot.isSuperAccessor, denot)
+              assert(!denot.symbol.isSuperAccessor, denot)
             else {
-              assert(denot.is(ParamAccessor) || denot.isSuperAccessor, denot)
+              assert(denot.is(ParamAccessor) || denot.symbol.isSuperAccessor, denot)
               def disambiguate(alt: Symbol) = // !!! DEBUG
                 trace.onDebug(s"disambiguating ${denot.info} =:= ${denot.owner.thisType.memberInfo(alt)} ${denot.owner}") {
                   denot.info matches denot.owner.thisType.memberInfo(alt)

compiler/src/dotty/tools/dotc/interactive/Completion.scala

@@ -7,12 +7,12 @@ import dotty.tools.dotc.ast.untpd
 import dotty.tools.dotc.config.Printers.interactiv
 import dotty.tools.dotc.core.Contexts._
 import dotty.tools.dotc.core.CheckRealizable
-import dotty.tools.dotc.core.Decorators.StringInterpolators
+import dotty.tools.dotc.core.Decorators._
 import dotty.tools.dotc.core.Denotations.SingleDenotation
 import dotty.tools.dotc.core.Flags._
 import dotty.tools.dotc.core.Names.{Name, TermName}
 import dotty.tools.dotc.core.NameKinds.SimpleNameKind
-import dotty.tools.dotc.core.NameOps.NameDecorator
+import dotty.tools.dotc.core.NameOps._
 import dotty.tools.dotc.core.Symbols.{NoSymbol, Symbol, defn}
 import dotty.tools.dotc.core.Scopes
 import dotty.tools.dotc.core.StdNames.{nme, tpnme}

compiler/src/dotty/tools/dotc/interactive/Interactive.scala

@@ -9,7 +9,7 @@ import ast.{NavigateAST, Trees, tpd, untpd}
 import core._
 import Decorators._, ContextOps._
 import Contexts._, Flags._, Names._, NameOps._, Symbols._, Trees._, Types._
-import transform.SymUtils.decorateSymbol
+import transform.SymUtils._
 import util.Spans._, util.SourceFile, util.SourcePosition
 import core.Denotations.SingleDenotation
 import NameKinds.SimpleNameKind

compiler/src/dotty/tools/dotc/parsing/Parsers.scala

@@ -64,12 +64,11 @@ object Parsers {
     val Spliced = 2
   }
 
-  private implicit class AddDeco(val buf: ListBuffer[Tree]) extends AnyVal {
+  extension (buf: ListBuffer[Tree]):
     def +++=(x: Tree) = x match {
       case x: Thicket => buf ++= x.trees
       case x => buf += x
     }
-  }
 
   /** The parse starting point depends on whether the source file is self-contained:
    *  if not, the AST will be supplemented.

compiler/src/dotty/tools/dotc/printing/Texts.scala

@@ -168,9 +168,9 @@ object Texts {
     /** The given texts `xs`, each on a separate line */
     def lines(xs: Traversable[Text]): Vertical = Vertical(xs.toList.reverse)
 
-    implicit class textDeco(text: => Text) {
+    extension (text: => Text):
       def provided(cond: Boolean): Text = if (cond) text else Str("")
-    }
+
   }
 
   case class Str(s: String, lineRange: LineRange = EmptyLineRange) extends Text {

compiler/src/dotty/tools/dotc/printing/package.scala

@@ -22,8 +22,8 @@ package object printing {
   val XprintMode: Key[Unit] = new Key
 
   /** @pre `nel` is non-empty list */
-  private[printing] implicit class ListOps[A](val nel: List[A]) extends AnyVal {
-    def intersperse(a: A): List[A] =
+  extension [A](nel: List[A]):
+    private[printing] def intersperse(a: A): List[A] =
       nel.flatMap(a :: _ :: Nil).tail
-  }
+
 }

compiler/src/dotty/tools/dotc/reporting/Reporter.scala

@@ -5,7 +5,7 @@ package reporting
 import scala.annotation.internal.sharable
 
 import core.Contexts._
-import core.Decorators.PhaseListDecorator
+import core.Decorators._
 import collection.mutable
 import core.Mode
 import dotty.tools.dotc.core.Symbols.{Symbol, NoSymbol}