Rework reflect show API

* Add `reflect.Printer[T]` type class
* Define `show` method in reflect based on `Printer`
* Provide a single default `show` for `Expr` and `Type` (use `reflect` to access other printers)
* Only define printers that make sence for the given types.
* Remove `Symbol.show`. Use directly `Symbol.fullName` instead.

Author: nicolasstucki

community-build/community-projects/verify

@@ -334,8 +334,8 @@ object Matcher {
                    |
                    |with environment: ${summon[Env]}
                    |
-                   |Scrutinee: ${scrutinee.showExtractors}
-                   |Pattern: ${pattern.showExtractors}
+                   |Scrutinee: ${scrutinee.show(using Printer.TreeStructure)}
+                   |Pattern: ${pattern.show(using Printer.TreeStructure)}
                    |
                    |""".stripMargin)
             notMatched

compiler/src/scala/quoted/runtime/impl/Matcher.scala

@@ -29,10 +29,10 @@ object QuotesImpl {
     new QuotesImpl
 
   def showDecompiledTree(tree: tpd.Tree)(using Context): String =
-    import qctx.reflect.TreeMethods.{showAnsiColored, show}
+    import qctx.reflect.Printer.{TreeCode, TreeAnsiCode}
     val qctx: QuotesImpl = new QuotesImpl(using MacroExpansion.context(tree))
-    if ctx.settings.color.value == "always" then showAnsiColored(tree)
-    else show(tree)
+    if ctx.settings.color.value == "always" then TreeAnsiCode.show(tree)
+    else TreeCode.show(tree)
 
   // TODO Explore more fine grained scope ids.
   //      This id can only differentiate scope extrusion from one compiler instance to another.
@@ -48,10 +48,7 @@ class QuotesImpl private (using val ctx: Context) extends Quotes, QuoteUnpickler
 
   extension [T](self: scala.quoted.Expr[T]):
     def show: String =
-      reflect.TreeMethods.show(reflect.Term.of(self))
-
-    def showAnsiColored: String =
-      reflect.TreeMethods.showAnsiColored(reflect.Term.of(self))
+      reflect.Printer.TreeCode.show(reflect.Term.of(self))
 
     def matches(that: scala.quoted.Expr[Any]): Boolean =
       treeMatch(reflect.Term.of(self), reflect.Term.of(that)).nonEmpty
@@ -70,8 +67,8 @@ class QuotesImpl private (using val ctx: Context) extends Quotes, QuoteUnpickler
       else
         throw Exception(
           s"""Expr cast exception: ${self.show}
-            |of type: ${reflect.TypeReprMethods.show(reflect.Term.of(self).tpe)}
-            |did not conform to type: ${reflect.TypeReprMethods.show(reflect.TypeRepr.of[X])}
+            |of type: ${reflect.Printer.TypeReprCode.show(reflect.Term.of(self).tpe)}
+            |did not conform to type: ${reflect.Printer.TypeReprCode.show(reflect.TypeRepr.of[X])}
             |""".stripMargin
         )
     }
@@ -89,14 +86,7 @@ class QuotesImpl private (using val ctx: Context) extends Quotes, QuoteUnpickler
       extension (self: Tree):
         def pos: Position = self.sourcePos
         def symbol: Symbol = self.symbol
-        def showExtractors: String =
-          Extractors.showTree(using QuotesImpl.this)(self)
-        def show: String =
-          SourceCode.showTree(using QuotesImpl.this)(self)(SyntaxHighlight.plain, fullNames = true)
-        def showShort: String =
-          SourceCode.showTree(using QuotesImpl.this)(self)(SyntaxHighlight.plain, fullNames = false)
-        def showAnsiColored: String =
-          SourceCode.showTree(using QuotesImpl.this)(self)(SyntaxHighlight.ANSI, fullNames = true)
+        def show(using printer: Printer[Tree]): String = printer.show(self)
         def isExpr: Boolean =
           self match
             case TermTypeTest(self) =>
@@ -1607,17 +1597,8 @@ class QuotesImpl private (using val ctx: Context) extends Quotes, QuoteUnpickler
 
     given TypeReprMethods: TypeReprMethods with
       extension (self: TypeRepr):
-        def showExtractors: String =
-          Extractors.showType(using QuotesImpl.this)(self)
-
-        def show: String =
-          SourceCode.showType(using QuotesImpl.this)(self)(SyntaxHighlight.plain, fullNames = true)
 
-        def showShort: String =
-          SourceCode.showType(using QuotesImpl.this)(self)(SyntaxHighlight.plain, fullNames = false)
-
-        def showAnsiColored: String =
-          SourceCode.showType(using QuotesImpl.this)(self)(SyntaxHighlight.ANSI, fullNames = true)
+        def show(using printer: Printer[TypeRepr]): String = printer.show(self)
 
         def seal: scala.quoted.Type[_] = self.asType
 
@@ -2175,14 +2156,7 @@ class QuotesImpl private (using val ctx: Context) extends Quotes, QuoteUnpickler
     given ConstantMethods: ConstantMethods with
       extension (self: Constant):
         def value: Any = self.value
-        def showExtractors: String =
-          Extractors.showConstant(using QuotesImpl.this)(self)
-        def show: String =
-          SourceCode.showConstant(using QuotesImpl.this)(self)(SyntaxHighlight.plain, fullNames = true)
-        def showShort: String =
-          SourceCode.showConstant(using QuotesImpl.this)(self)(SyntaxHighlight.plain, fullNames = false)
-        def showAnsiColored: String =
-          SourceCode.showConstant(using QuotesImpl.this)(self)(SyntaxHighlight.ANSI, fullNames = true)
+        def show(using printer: Printer[Constant]): String = printer.show(self)
       end extension
     end ConstantMethods
 
@@ -2404,12 +2378,7 @@ class QuotesImpl private (using val ctx: Context) extends Quotes, QuoteUnpickler
         def companionModule: Symbol = self.denot.companionModule
         def children: List[Symbol] = self.denot.children
 
-        def showExtractors: String =
-          Extractors.showSymbol(using QuotesImpl.this)(self)
-        def show: String =
-          SourceCode.showSymbol(using QuotesImpl.this)(self)(SyntaxHighlight.plain)
-        def showAnsiColored: String =
-          SourceCode.showSymbol(using QuotesImpl.this)(self)(SyntaxHighlight.ANSI)
+        def show(using printer: Printer[Symbol]): String = printer.show(self)
 
       end extension
 
@@ -2548,12 +2517,7 @@ class QuotesImpl private (using val ctx: Context) extends Quotes, QuoteUnpickler
         def is(that: Flags): Boolean = self.isAllOf(that)
         def |(that: Flags): Flags = dotc.core.Flags.or(self, that) // TODO: Replace with dotc.core.Flags.|(self)(that)  once extension names have stabilized
         def &(that: Flags): Flags = dotc.core.Flags.and(self, that)// TODO: Replace with dotc.core.Flags.&(self)(that)  once extension names have stabilized
-        def showExtractors: String =
-          Extractors.showFlags(using QuotesImpl.this)(self)
-        def show: String =
-          SourceCode.showFlags(using QuotesImpl.this)(self)(SyntaxHighlight.plain)
-        def showAnsiColored: String =
-          SourceCode.showFlags(using QuotesImpl.this)(self)(SyntaxHighlight.ANSI)
+        def show(using printer: Printer[Flags]): String = printer.show(self)
       end extension
     end FlagsMethods
 
@@ -2684,18 +2648,69 @@ class QuotesImpl private (using val ctx: Context) extends Quotes, QuoteUnpickler
                    |
                    |
                    |The code of the definition of ${t.symbol} is
-                   |${TreeMethods.show(t)}
+                   |${Printer.TreeCode.show(t)}
                    |
                    |which was found in the code
-                   |${TreeMethods.show(tree)}
+                   |${Printer.TreeCode.show(tree)}
                    |
                    |which has the AST representation
-                   |${TreeMethods.showExtractors(tree)}
+                   |${Printer.TreeStructure.show(tree)}
                    |
                    |""".stripMargin)
             case _ => traverseChildren(t)
       }.traverse(tree)
 
+    object Printer extends PrinterModule:
+
+      lazy val TreeCode: Printer[Tree] = new Printer[Tree]:
+        def show(tree: Tree): String =
+          SourceCode.showTree(using QuotesImpl.this)(tree)(SyntaxHighlight.plain, fullNames = true)
+
+      lazy val TreeShortCode: Printer[Tree] = new Printer[Tree]:
+        def show(tree: Tree): String =
+          SourceCode.showTree(using QuotesImpl.this)(tree)(SyntaxHighlight.plain, fullNames = false)
+
+      lazy val TreeAnsiCode: Printer[Tree] = new Printer[Tree]:
+        def show(tree: Tree): String =
+          SourceCode.showTree(using QuotesImpl.this)(tree)(SyntaxHighlight.ANSI, fullNames = true)
+
+      lazy val TreeStructure: Printer[Tree] = new Printer[Tree]:
+        def show(tree: Tree): String =
+          Extractors.showTree(using QuotesImpl.this)(tree)
+
+      lazy val TypeReprCode: Printer[TypeRepr] = new Printer[TypeRepr]:
+        def show(tpe: TypeRepr): String =
+          SourceCode.showType(using QuotesImpl.this)(tpe)(SyntaxHighlight.plain, fullNames = true)
+
+      lazy val TypeReprShortCode: Printer[TypeRepr] = new Printer[TypeRepr]:
+        def show(tpe: TypeRepr): String =
+          SourceCode.showType(using QuotesImpl.this)(tpe)(SyntaxHighlight.plain, fullNames = false)
+
+      lazy val TypeReprAnsiCode: Printer[TypeRepr] = new Printer[TypeRepr]:
+        def show(tpe: TypeRepr): String =
+          SourceCode.showType(using QuotesImpl.this)(tpe)(SyntaxHighlight.ANSI, fullNames = true)
+
+      lazy val TypeReprStructure: Printer[TypeRepr] = new Printer[TypeRepr]:
+        def show(tpe: TypeRepr): String =
+          Extractors.showType(using QuotesImpl.this)(tpe)
+
+      lazy val ConstantCode: Printer[Constant] = new Printer[Constant]:
+        def show(const: Constant): String =
+          SourceCode.showConstant(using QuotesImpl.this)(const)(SyntaxHighlight.plain, fullNames = true)
+
+      lazy val ConstantAnsiCode: Printer[Constant] = new Printer[Constant]:
+        def show(const: Constant): String =
+          SourceCode.showConstant(using QuotesImpl.this)(const)(SyntaxHighlight.ANSI, fullNames = true)
+
+      lazy val ConstantCase: Printer[Constant] = new Printer[Constant]:
+        def show(const: Constant): String =
+          Extractors.showConstant(using QuotesImpl.this)(const)
+
+      lazy val FlagsCombination: Printer[Flags] = new Printer[Flags]:
+        def show(flags: Flags): String =
+          Extractors.showFlags(using QuotesImpl.this)(flags)
+
+    end Printer
   end reflect
 
   def unpickleExpr[T](pickled: String | List[String], typeHole: (Int, Seq[Any]) => scala.quoted.Type[?], termHole: (Int, Seq[Any], scala.quoted.Quotes) => scala.quoted.Expr[?]): scala.quoted.Expr[T] =

compiler/src/scala/quoted/runtime/impl/QuotesImpl.scala

@@ -188,7 +188,7 @@ object SourceCode {
           case Select(newTree: New, _) =>
             printType(newTree.tpe)(using Some(cdef.symbol))
           case parent: Term =>
-            throw new MatchError(parent.showExtractors)
+            throw new MatchError(parent.show(using Printer.TreeStructure))
         }
 
         def printSeparated(list: List[Tree /* Term | TypeTree */]): Unit = list match {
@@ -535,7 +535,7 @@ object SourceCode {
         printTree(meth)
 
       case _ =>
-        throw new MatchError(tree.showExtractors)
+        throw new MatchError(tree.show(using Printer.TreeStructure))
 
     }
 
@@ -922,7 +922,7 @@ object SourceCode {
           case Ident("unapply" | "unapplySeq") =>
             this += fun.symbol.owner.fullName.stripSuffix("$")
           case _ =>
-            throw new MatchError(fun.showExtractors)
+            throw new MatchError(fun.show(using Printer.TreeStructure))
         }
         inParens(printPatterns(patterns, ", "))
 
@@ -937,7 +937,7 @@ object SourceCode {
         printTree(v)
 
       case _ =>
-        throw new MatchError(pattern.showExtractors)
+        throw new MatchError(pattern.show(using Printer.TreeStructure))
 
     }
 
@@ -1063,7 +1063,7 @@ object SourceCode {
         printTypeTree(tpt)
 
       case _ =>
-        throw new MatchError(tree.showExtractors)
+        throw new MatchError(tree.show(using Printer.TreeStructure))
 
     }
 
@@ -1233,7 +1233,7 @@ object SourceCode {
         printType(hi)
 
       case _ =>
-        throw new MatchError(tpe.showExtractors)
+        throw new MatchError(tpe.show(using Printer.TypeReprStructure))
     }
 
     private def printSelector(sel: Selector): this.type = sel match {
@@ -1272,7 +1272,7 @@ object SourceCode {
           val sym = annot.tpe.typeSymbol
           sym != Symbol.requiredClass("scala.forceInline") &&
           sym.maybeOwner != Symbol.requiredPackage("scala.annotation.internal")
-        case x => throw new MatchError(x.showExtractors)
+        case x => throw new MatchError(x.show(using Printer.TreeStructure))
       }
       printAnnotations(annots)
       if (annots.nonEmpty) this += " "