Rewrite and adapt to Scala 3 features (#51)

Rewrite and adapt to Scala 3 features
lampepfl · Mar 25, 2024 · 71c6c4b · 71c6c4b
2 parents 1600462 + 0540802
commit 71c6c4b
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Showing 13 changed files with 190 additions and 193 deletions.
diff --git a/build.sbt b/build.sbt
@@ -8,7 +8,7 @@ lazy val root = project
 
     scalaVersion := dottyVersion,
     scalacOptions ++= Seq(
-      "-deprecation"
+      "-deprecation", "-feature", "-language:implicitConversions"
     ),
     libraryDependencies ++= Seq(
       "org.scala-lang.modules" % "scala-parser-combinators_2.13" % "1.1.2",

diff --git a/src/main/scala/dotty/xml/interpolator/internal/Expand.scala b/src/main/scala/dotty/xml/interpolator/internal/Expand.scala
@@ -1,20 +1,18 @@
 package dotty.xml.interpolator
 package internal
 
-import scala.language.implicitConversions
 import scala.quoted._
 
-import dotty.xml.interpolator.internal.Tree._
+import Tree.*
 
-object Expand {
+object Expand:
 
-  def apply(nodes: Seq[Node])(implicit ctx: XmlContext, q: Quotes): Expr[scala.xml.Node | scala.xml.NodeBuffer] = {
-    if (nodes.size == 1) expandNode(nodes.head).asInstanceOf[Expr[scala.xml.Node]]
+  def apply(nodes: Seq[Node])(using XmlContext, Quotes): Expr[scala.xml.Node | scala.xml.NodeBuffer] =
+    if nodes.size == 1 then expandNode(nodes.head).asInstanceOf[Expr[scala.xml.Node]]
     else expandNodes(nodes)
-  }
 
-  private def expandNode(node: Node)(implicit ctx: XmlContext, q: Quotes): Expr[Any] = {
-    node match {
+  private def expandNode(node: Node)(using XmlContext, Quotes): Expr[Any] =
+    node match
       case group: Group             => expandGroup(group)
       case elem: Elem               => expandElem(elem)
       case text: Text               => expandText(text)
@@ -24,33 +22,32 @@ object Expand {
       case procInstr: ProcInstr     => expandProcInstr(procInstr)
       case entityRef: EntityRef     => expandEntityRef(entityRef)
       case unparsed: Unparsed       => expandUnparsed(unparsed)
-    }
-  }
+  end expandNode
 
-  private def expandNodes(nodes: Seq[Node])(implicit ctx: XmlContext, q: Quotes): Expr[scala.xml.NodeBuffer] = {
-    nodes.foldLeft('{ new _root_.scala.xml.NodeBuffer() })((expr, node) => '{ $expr &+ ${expandNode(node)} } )
-  }
+  private def expandNodes(nodes: Seq[Node])(using XmlContext, Quotes): Expr[scala.xml.NodeBuffer] =
+    nodes.foldLeft('{ scala.xml.NodeBuffer() }): (expr, node) => 
+      '{ $expr &+ ${ expandNode(node) } }
 
-  private def expandGroup(group: Group)(implicit ctx: XmlContext, q: Quotes): Expr[scala.xml.Group] =
-    '{ new _root_.scala.xml.Group(${expandNodes(group.nodes)}) }
+  private def expandGroup(group: Group)(using XmlContext, Quotes): Expr[scala.xml.Group] =
+    '{ scala.xml.Group(${ expandNodes(group.nodes) }) }
 
-  private def expandElem(elem: Elem)(implicit ctx: XmlContext, q: Quotes): Expr[scala.xml.Elem] = {
+  private def expandElem(elem: Elem)(using ctx: XmlContext, q: Quotes): Expr[scala.xml.Elem] =
     val (namespaces, attributes) = elem.attributes.partition(_.isNamespace)
-    val prefix = if (elem.prefix.nonEmpty) Expr(elem.prefix) else '{ null: String }
+    val prefix = if elem.prefix.nonEmpty then Expr(elem.prefix) else '{ null }
     val label = Expr(elem.label)
     val attributes1 = expandAttributes(attributes)
     val scope = expandNamespaces(namespaces)
     val empty = Expr(elem.end.isEmpty)
-    val child = expandNodes(elem.children)(new XmlContext(ctx.args, scope), q)
-    if (elem.children.isEmpty)
-      '{ new _root_.scala.xml.Elem($prefix, $label, $attributes1, $scope, $empty) }
+    val child = expandNodes(elem.children)(using new XmlContext(ctx.args, scope), q)
+    if elem.children.isEmpty then
+      '{ new scala.xml.Elem($prefix, $label, $attributes1, $scope, $empty) }
     else
-      '{ new _root_.scala.xml.Elem($prefix, $label, $attributes1, $scope, $empty, _root_.scala.xml.NodeSeq.seqToNodeSeq($child): _*) }
-  }
+      '{ new scala.xml.Elem($prefix, $label, $attributes1, $scope, $empty, scala.xml.NodeSeq.seqToNodeSeq($child)*) }
+  end expandElem
 
-  private def expandAttributes(attributes: Seq[Attribute])(implicit ctx: XmlContext, q: Quotes): Expr[scala.xml.MetaData] = {
+  private def expandAttributes(attributes: Seq[Attribute])(using XmlContext, Quotes): Expr[scala.xml.MetaData] =
     import quotes.reflect._
-    attributes.foldRight('{ _root_.scala.xml.Null }: Expr[scala.xml.MetaData])((attribute, rest) => {
+    attributes.foldRight('{ _root_.scala.xml.Null }: Expr[scala.xml.MetaData]): (attribute, rest) =>
       val value = attribute.value match {
           case Seq(v) => expandNode(v)
           case vs     => expandNodes(vs)
@@ -71,57 +68,52 @@ object Expand {
       */
 
       val term = value.asTerm
-      if (term.tpe <:< TypeRepr.of[String]) {
+      if term.tpe <:< TypeRepr.of[String] then
         val value = term.asExprOf[String]
-        if (attribute.prefix.isEmpty) '{ new _root_.scala.xml.UnprefixedAttribute(${Expr(attribute.key)}, $value, $rest) }
-        else '{ new _root_.scala.xml.PrefixedAttribute(${Expr(attribute.prefix)}, ${Expr(attribute.key)}, $value, $rest) }
-      } else if (term.tpe <:< TypeRepr.of[collection.Seq[scala.xml.Node]]) {
+        if attribute.prefix.isEmpty then '{ scala.xml.UnprefixedAttribute(${ Expr(attribute.key) }, $value, $rest) }
+        else '{ scala.xml.PrefixedAttribute(${ Expr(attribute.prefix) }, ${ Expr(attribute.key) }, $value, $rest) }
+      else if term.tpe <:< TypeRepr.of[collection.Seq[scala.xml.Node]] then 
         val value = term.asExprOf[collection.Seq[scala.xml.Node]]
-        if (attribute.prefix.isEmpty) '{ new _root_.scala.xml.UnprefixedAttribute(${Expr(attribute.key)}, $value, $rest) }
-        else '{ new _root_.scala.xml.PrefixedAttribute(${Expr(attribute.prefix)}, ${Expr(attribute.key)}, $value, $rest) }
-      } else {
+        if attribute.prefix.isEmpty then '{ scala.xml.UnprefixedAttribute(${ Expr(attribute.key) }, $value, $rest) }
+        else '{ scala.xml.PrefixedAttribute(${ Expr(attribute.prefix) }, ${ Expr(attribute.key) }, $value, $rest) }
+      else
         val value = term.asExprOf[Option[collection.Seq[scala.xml.Node]]]
-        if (attribute.prefix.isEmpty) '{ new _root_.scala.xml.UnprefixedAttribute(${Expr(attribute.key)}, $value, $rest) }
-        else '{ new _root_.scala.xml.PrefixedAttribute(${Expr(attribute.prefix)}, ${Expr(attribute.key)}, $value, $rest) }
-      }
-    })
-  }
+        if attribute.prefix.isEmpty then '{ scala.xml.UnprefixedAttribute(${ Expr(attribute.key) }, $value, $rest) }
+        else '{ scala.xml.PrefixedAttribute(${ Expr(attribute.prefix) }, ${ Expr(attribute.key) }, $value, $rest) }
+  end expandAttributes
 
-  private def expandNamespaces(namespaces: Seq[Attribute])(implicit ctx: XmlContext, q: Quotes): Expr[scala.xml.NamespaceBinding] = {
+  private def expandNamespaces(namespaces: Seq[Attribute])(using XmlContext, Quotes): Expr[Scope] = 
     import quotes.reflect._
-    namespaces.foldLeft(ctx.scope)((rest, namespace) => {
-      val prefix = if (namespace.prefix.nonEmpty) Expr(namespace.key) else '{ null: String }
-      val uri = (namespace.value.head: @unchecked) match {
+    namespaces.foldLeft(ctx.scope): (rest, namespace) =>
+      val prefix = if namespace.prefix.nonEmpty then Expr(namespace.key) else '{ null }
+      val uri = (namespace.value.head: @unchecked) match
         case Text(text) => Expr(text)
         case Placeholder(id) =>
-          val call = '{ ${ctx.args(id)}(using _root_.scala.xml.TopScope) }
+          val call = '{ ${ctx.args(id)}(using scala.xml.TopScope) }
           Expr.betaReduce(call).asExprOf[String]
-      }
-      '{ new _root_.scala.xml.NamespaceBinding($prefix, $uri, $rest) }
-    })
-  }
+      '{ scala.xml.NamespaceBinding($prefix, $uri, $rest) }
+  end expandNamespaces
 
   private def expandText(text: Text)(using Quotes): Expr[scala.xml.Text] =
-    '{ new _root_.scala.xml.Text(${Expr(text.text)}) }
+    '{ scala.xml.Text(${ Expr(text.text) }) }
 
   private def expandComment(comment: Comment)(using Quotes): Expr[scala.xml.Comment] =
-    '{ new _root_.scala.xml.Comment(${Expr(comment.text)}) }
+    '{ scala.xml.Comment(${ Expr(comment.text) }) }
 
-  private def expandPlaceholder(placeholder: Placeholder)(implicit ctx: XmlContext, q: Quotes): Expr[Any] = {
+  private def expandPlaceholder(placeholder: Placeholder)(using XmlContext, Quotes): Expr[Any] =
     val arg = ctx.args(placeholder.id)
-    val scope = ctx.scope
-    Expr.betaReduce('{ $arg(using $scope) })
-  }
+    Expr.betaReduce('{ $arg(using ${ ctx.scope }) })
 
   private def expandPCData(pcdata: PCData)(using Quotes): Expr[scala.xml.PCData] =
-    '{ new _root_.scala.xml.PCData(${Expr(pcdata.data)}) }
+    '{ scala.xml.PCData(${ Expr(pcdata.data) }) }
 
   private def expandProcInstr(instr: ProcInstr)(using Quotes): Expr[scala.xml.ProcInstr] =
-    '{ new _root_.scala.xml.ProcInstr(${Expr(instr.target)}, ${Expr(instr.proctext)}) }
+    '{ scala.xml.ProcInstr(${ Expr(instr.target) }, ${ Expr(instr.proctext) }) }
 
   private def expandEntityRef(ref: EntityRef)(using Quotes): Expr[scala.xml.EntityRef] =
-    '{ new _root_.scala.xml.EntityRef(${Expr(ref.name)}) }
+    '{ scala.xml.EntityRef(${ Expr(ref.name) }) }
 
   private def expandUnparsed(unparsed: Unparsed)(using Quotes): Expr[scala.xml.Unparsed] =
-    '{ new _root_.scala.xml.Unparsed(${Expr(unparsed.data)}) }
-}
+    '{ scala.xml.Unparsed(${ Expr(unparsed.data) }) }
+
+end Expand
diff --git a/src/main/scala/dotty/xml/interpolator/internal/Hole.scala b/src/main/scala/dotty/xml/interpolator/internal/Hole.scala
@@ -1,8 +1,7 @@
 package dotty.xml.interpolator
 package internal
 
-object Hole {
+object Hole:
   val HoleStart = 0xE000.toChar.toString
   val HoleChar  = 0xE001.toChar.toString
-  def encode(i: Int) = HoleStart + HoleChar * i
-}
+  def encode(i: Int) = HoleStart + HoleChar * i
diff --git a/src/main/scala/dotty/xml/interpolator/internal/Macro.scala b/src/main/scala/dotty/xml/interpolator/internal/Macro.scala
@@ -6,38 +6,43 @@ import scala.quoted._
 import scala.collection.mutable.ArrayBuffer
 import scala.language.implicitConversions
 
-object Macro {
+object Macro:
 
-  def impl(strCtxExpr: Expr[StringContext], argsExpr: Expr[Seq[Scope ?=> Any]], scope: Expr[Scope])(using qctx: Quotes): Expr[scala.xml.Node | scala.xml.NodeBuffer] = {
-    ((strCtxExpr, argsExpr): @unchecked) match {
+  /** ??? */
+  def impl(strCtxExpr: Expr[StringContext], argsExpr: Expr[Seq[Scope ?=> Any]], scope: Expr[Scope])
+          (using Quotes): Expr[scala.xml.Node | scala.xml.NodeBuffer] =
+
+    (strCtxExpr, argsExpr) match
       case ('{ StringContext(${Varargs(parts)}: _*) }, Varargs(args)) =>
+
         val (xmlStr, offsets) = encode(parts)
-        implicit val ctx: XmlContext = new XmlContext(args, scope)
-        implicit val reporter: Reporter = new Reporter {
-          import quotes.reflect._
 
-          def error(msg: String, idx: Int): Unit = {
-            val (part, offset) = Reporter.from(idx, offsets, parts)
-            val pos = part.asTerm.pos
-            val (srcF, start) = (pos.sourceFile, pos.start)
-            report.error(msg, Position(srcF, start + offset, start + offset + 1))
-          }
+        given XmlContext = new XmlContext(args, scope)
+        given Reporter = new Reporter {
+            import quotes.reflect.*
+
+            def error(msg: String, idx: Int): Unit = {
+              val (part, offset) = Reporter.from(idx, offsets, parts)
+              val pos = part.asTerm.pos
+              val (srcF, start) = (pos.sourceFile, pos.start)
+              report.error(msg, Position(srcF, start + offset, start + offset + 1))
+            }
+
+            def error(msg: String, expr: Expr[Any]): Unit =
+              report.error(msg, expr)
+           }
 
-          def error(msg: String, expr: Expr[Any]): Unit = {
-            report.error(msg, expr)
-          }
-        }
         implCore(xmlStr)
-    }
-  }
+  end impl
 
-  def implErrors(strCtxExpr: Expr[StringContext], argsExpr: Expr[Seq[Scope ?=> Any]], scope: Expr[Scope])(using qctx: Quotes): Expr[List[(Int, String)]] = {
-    ((strCtxExpr, argsExpr): @unchecked) match {
+  def implErrors(strCtxExpr: Expr[StringContext], argsExpr: Expr[Seq[Scope ?=> Any]], scope: Expr[Scope])
+                (using Quotes): Expr[List[(Int, String)]] =
+    (strCtxExpr, argsExpr) match
       case ('{ StringContext(${Varargs(parts)}: _*) }, Varargs(args)) =>
         val errors = List.newBuilder[Expr[(Int, String)]]
         val (xmlStr, offsets) = encode(parts)
-        implicit val ctx: XmlContext = new XmlContext(args, scope)
-        implicit val reporter: Reporter = new Reporter {
+        given XmlContext = new XmlContext(args, scope)
+        given Reporter = new Reporter {
           import quotes.reflect._
 
           def error(msg: String, idx: Int): Unit = {
@@ -53,48 +58,43 @@ object Macro {
         }
         implCore(xmlStr)
         Expr.ofList(errors.result())
-    }
-  }
+  end implErrors
 
-  private def implCore(xmlStr: String)(using XmlContext, Reporter, Quotes): Expr[scala.xml.Node | scala.xml.NodeBuffer] = {
+  private def implCore(xmlStr: String)(using XmlContext, Reporter, Quotes): Expr[scala.xml.Node | scala.xml.NodeBuffer] =
 
-    import Parse.{apply => parse}
-    import Transform.{apply => transform}
-    import Validate.{apply => validate}
-    import TypeCheck.{apply => typecheck}
-    import Expand.{apply => expand}
+    import Parse.apply as parse
+    import Transform.apply as transform
+    import Validate.apply as validate
+    import TypeCheck.apply as typecheck
+    import Expand.apply as expand
 
-    val interpolate = (
-      parse
-        andThen transform
-        andThen validate
-        andThen typecheck
-        andThen expand
-    )
+    val interpolate = 
+      parse andThen 
+      transform andThen 
+      validate andThen 
+      typecheck andThen
+      expand
 
     interpolate(xmlStr)
-  }
+  end implCore
 
-  private def encode(parts: Seq[Expr[String]])(using Quotes): (String, Array[Int]) = {
+  private def encode(parts: Seq[Expr[String]])(using Quotes): (String, Array[Int]) =
     val sb = new StringBuilder()
     val bf = ArrayBuffer.empty[Int]
 
-    def appendPart(part: Expr[String]) = {
+    def appendPart(part: Expr[String]) =
       bf += sb.length
       sb ++= part.valueOrAbort
       bf += sb.length
-    }
 
-    def appendHole(index: Int) = {
-      sb ++= Hole.encode(index)
-    }
+    def appendHole(index: Int) = sb ++= Hole.encode(index)
 
-    for ((part, index) <- parts.init.zipWithIndex) {
+    for (part, index) <- parts.init.zipWithIndex do
       appendPart(part)
       appendHole(index)
-    }
     appendPart(parts.last)
 
     (sb.toString, bf.toArray)
-  }
-}
+  end encode
+
+end Macro
diff --git a/src/main/scala/dotty/xml/interpolator/internal/Reporter.scala b/src/main/scala/dotty/xml/interpolator/internal/Reporter.scala
@@ -1,14 +1,13 @@
 package dotty.xml.interpolator
 package internal
 
-import scala.quoted._
+import scala.quoted.*
 
-trait Reporter {
+trait Reporter:
   def error(msg: String, idx: Int): Unit
   def error(msg: String, expr: Expr[Any]): Unit
-}
 
-object Reporter {
+object Reporter:
   def from(idx: Int, offsets: Array[Int], parts: Seq[Expr[String]]): (Expr[String], Int) = {
     val index = offsets.lastIndexWhere(idx >= _)
     val isWithinHoleOrAtTheEnd = index % 2 != 0
@@ -17,5 +16,4 @@ object Reporter {
       case false => (index / 2, idx - offsets(index))
     }
     (parts(partIndex), offset)
-  }
-}
+  }
diff --git a/src/main/scala/dotty/xml/interpolator/internal/Transform.scala b/src/main/scala/dotty/xml/interpolator/internal/Transform.scala
@@ -1,16 +1,17 @@
 package dotty.xml.interpolator
 package internal
 
-import dotty.xml.interpolator.internal.Tree._
+import Tree.*
 
-object Transform {
-  def apply(nodes: Seq[Node]): Seq[Node] = {
-    nodes.map {
+object Transform:
+
+  def apply(nodes: Seq[Node]): Seq[Node] =
+    nodes.map:
       case elem : Elem =>
         val children = apply(elem.children)
-        if (elem.name == "xml:group" && !elem.end.isEmpty) Group(elem.children).setPos(elem.pos)
+        if elem.name == "xml:group" && !elem.end.isEmpty then Group(elem.children).setPos(elem.pos)
         else elem.copy(children = children).setPos(elem.pos)
       case node => node
-    }
-  }
-}
+  end apply
+
+end Transform