Merge pull request #8665 from dotty-staging/fix-#8585-2

Fix #8585: Refresh names to avoid name clashes

library/src/scala/tasty/reflect/SourceCodePrinter.scala

@@ -324,7 +324,7 @@ class SourceCodePrinter[R <: Reflection & Singleton](val tasty: R)(syntaxHighlig
 
       case tree: Ident =>
         splicedName(tree.symbol) match {
-          case Some(name) => this += name
+          case Some(name) => this += highlightTypeDef(name)
           case _ => printType(tree.tpe)
         }
 
@@ -834,7 +834,7 @@ class SourceCodePrinter[R <: Reflection & Singleton](val tasty: R)(syntaxHighlig
     }
 
     def printParamDef(arg: ValDef)(using elideThis: Option[Symbol]): Unit = {
-      val name = arg.name
+      val name = splicedName(arg.symbol).getOrElse(arg.symbol.name)
       val sym = arg.symbol.owner
       if sym.isDefDef && sym.name == "<init>" then
         val ClassDef(_, _, _, _, _, body) = sym.owner.tree
@@ -1409,11 +1409,26 @@ class SourceCodePrinter[R <: Reflection & Singleton](val tasty: R)(syntaxHighlig
     private def escapedString(str: String): String = str flatMap escapedChar
   }
 
+  private[this] val names = collection.mutable.Map.empty[Symbol, String]
+  private[this] val namesIndex = collection.mutable.Map.empty[String, Int]
+
   private def splicedName(sym: Symbol)(using ctx: Context): Option[String] = {
     sym.annots.find(_.symbol.owner == ctx.requiredClass("scala.internal.quoted.showName")).flatMap {
       case Apply(_, Literal(Constant(c: String)) :: Nil) => Some(c)
       case Apply(_, Inlined(_, _, Literal(Constant(c: String))) :: Nil) => Some(c)
       case annot => None
+    }.orElse {
+      if sym.owner.isClassDef then None
+      else names.get(sym).orElse {
+        val name0 = sym.name
+        val index = namesIndex.getOrElse(name0, 1)
+        namesIndex(name0) = index + 1
+        val name =
+          if index == 1 then name0
+          else s"`$name0${index.toString.toCharArray.map {x => (x - '0' + '₀').toChar}.mkString}`"
+        names(sym) = name
+        Some(name)
+      }
     }
   }
 

tests/run-macros/flops-rewrite.check

@@ -1,7 +1,7 @@
 scala.Nil.map[scala.Nothing](((x: scala.Nothing) => x))
 scala.Nil
 
-scala.Nil.map[scala.Nothing](((x: scala.Nothing) => x)).++[scala.Nothing](scala.Nil.map[scala.Nothing](((x: scala.Nothing) => x)))
+scala.Nil.map[scala.Nothing](((x: scala.Nothing) => x)).++[scala.Nothing](scala.Nil.map[scala.Nothing](((`x₂`: scala.Nothing) => `x₂`)))
 scala.Nil
 
 scala.Nil.map[scala.Nothing](((x: scala.Nothing) => x)).++[scala.Int](scala.List.apply[scala.Int](3)).++[scala.Int](scala.Nil)

tests/run-macros/quote-matching-optimize-1.check

@@ -1,18 +1,18 @@
-Original: ls.filter(((x: scala.Int) => x.<(3))).filter(((x: scala.Int) => x.>(1)))
+Original: ls.filter(((x: scala.Int) => x.<(3))).filter(((`x₂`: scala.Int) => `x₂`.>(1)))
 Optimized: ls.filter(((x: scala.Int) => x.<(3).&&(x.>(1))))
 Result: List(2)
 
-Original: ls2.filter(((x: scala.Char) => x.<('c'))).filter(((x: scala.Char) => x.>('a')))
+Original: ls2.filter(((x: scala.Char) => x.<('c'))).filter(((`x₂`: scala.Char) => `x₂`.>('a')))
 Optimized: ls2.filter(((x: scala.Char) => x.<('c').&&(x.>('a'))))
 Result: List(b)
 
-Original: ls.filter(((x: scala.Int) => x.<(3))).filter(((x: scala.Int) => x.>(1))).filter(((x: scala.Int) => x.==(2)))
+Original: ls.filter(((x: scala.Int) => x.<(3))).filter(((`x₂`: scala.Int) => `x₂`.>(1))).filter(((`x₃`: scala.Int) => `x₃`.==(2)))
 Optimized: ls.filter(((x: scala.Int) => x.<(3).&&(x.>(1).&&(x.==(2)))))
 Result: List(2)
 
 1
 2
-Original: ls.filter(((x: scala.Int) => x.<(3))).foreach[scala.Unit](((x: scala.Int) => scala.Predef.println(x)))
+Original: ls.filter(((x: scala.Int) => x.<(3))).foreach[scala.Unit](((`x₂`: scala.Int) => scala.Predef.println(`x₂`)))
 Optimized: ls.foreach[scala.Unit](((x: scala.Int) => if (x.<(3)) scala.Predef.println(x) else ()))
 Result: ()
 

tests/run-macros/quote-matching-optimize-2.check

@@ -1,18 +1,18 @@
-Original: ls.filter(((x: scala.Int) => x.<(3))).filter(((x: scala.Int) => x.>(1)))
+Original: ls.filter(((x: scala.Int) => x.<(3))).filter(((`x₂`: scala.Int) => `x₂`.>(1)))
 Optimized: ls.filter(((x: scala.Int) => x.<(3).&&(x.>(1))))
 Result: List(2)
 
-Original: ls2.filter(((x: scala.Char) => x.<('c'))).filter(((x: scala.Char) => x.>('a')))
+Original: ls2.filter(((x: scala.Char) => x.<('c'))).filter(((`x₂`: scala.Char) => `x₂`.>('a')))
 Optimized: ls2.filter(((x: scala.Char) => x.<('c').&&(x.>('a'))))
 Result: List(b)
 
-Original: ls.filter(((x: scala.Int) => x.<(3))).filter(((x: scala.Int) => x.>(1))).filter(((x: scala.Int) => x.==(2)))
+Original: ls.filter(((x: scala.Int) => x.<(3))).filter(((`x₂`: scala.Int) => `x₂`.>(1))).filter(((`x₃`: scala.Int) => `x₃`.==(2)))
 Optimized: ls.filter(((x: scala.Int) => x.<(3).&&(x.>(1).&&(x.==(2)))))
 Result: List(2)
 
 1
 2
-Original: ls.filter(((x: scala.Int) => x.<(3))).foreach[scala.Unit](((x: scala.Int) => scala.Predef.println(x)))
+Original: ls.filter(((x: scala.Int) => x.<(3))).foreach[scala.Unit](((`x₂`: scala.Int) => scala.Predef.println(`x₂`)))
 Optimized: ls.foreach[scala.Any](((x: scala.Int) => if (x.<(3)) scala.Predef.println(x) else ()))
 Result: ()
 

tests/run-macros/quote-matching-optimize-3.check

@@ -1,19 +1,19 @@
-Original: ls.filter(((x: scala.Int) => x.<(3))).filter(((x: scala.Int) => x.>(1)))
-Optimized: ls.filter(((x: scala.Int) => ((x: scala.Int) => x.<(3)).apply(x).&&(((x: scala.Int) => x.>(1)).apply(x))))
+Original: ls.filter(((x: scala.Int) => x.<(3))).filter(((`x₂`: scala.Int) => `x₂`.>(1)))
+Optimized: ls.filter(((x: scala.Int) => ((`x₂`: scala.Int) => `x₂`.<(3)).apply(x).&&(((`x₃`: scala.Int) => `x₃`.>(1)).apply(x))))
 Result: List(2)
 
-Original: ls2.filter(((x: scala.Char) => x.<('c'))).filter(((x: scala.Char) => x.>('a')))
-Optimized: ls2.filter(((x: scala.Char) => ((x: scala.Char) => x.<('c')).apply(x).&&(((x: scala.Char) => x.>('a')).apply(x))))
+Original: ls2.filter(((x: scala.Char) => x.<('c'))).filter(((`x₂`: scala.Char) => `x₂`.>('a')))
+Optimized: ls2.filter(((x: scala.Char) => ((`x₂`: scala.Char) => `x₂`.<('c')).apply(x).&&(((`x₃`: scala.Char) => `x₃`.>('a')).apply(x))))
 Result: List(b)
 
-Original: ls.filter(((x: scala.Int) => x.<(3))).filter(((x: scala.Int) => x.>(1))).filter(((x: scala.Int) => x.==(2)))
-Optimized: ls.filter(((x: scala.Int) => ((x: scala.Int) => x.<(3)).apply(x).&&(((x: scala.Int) => ((x: scala.Int) => x.>(1)).apply(x).&&(((x: scala.Int) => x.==(2)).apply(x))).apply(x))))
+Original: ls.filter(((x: scala.Int) => x.<(3))).filter(((`x₂`: scala.Int) => `x₂`.>(1))).filter(((`x₃`: scala.Int) => `x₃`.==(2)))
+Optimized: ls.filter(((x: scala.Int) => ((`x₂`: scala.Int) => `x₂`.<(3)).apply(x).&&(((`x₃`: scala.Int) => ((`x₄`: scala.Int) => `x₄`.>(1)).apply(`x₃`).&&(((`x₅`: scala.Int) => `x₅`.==(2)).apply(`x₃`))).apply(x))))
 Result: List(2)
 
 1
 2
-Original: ls.filter(((x: scala.Int) => x.<(3))).foreach[scala.Unit](((x: scala.Int) => scala.Predef.println(x)))
-Optimized: ls.foreach[scala.Any](((x: scala.Int) => if (((x: scala.Int) => x.<(3)).apply(x)) ((x: scala.Int) => scala.Predef.println(x)).apply(x) else ()))
+Original: ls.filter(((x: scala.Int) => x.<(3))).foreach[scala.Unit](((`x₂`: scala.Int) => scala.Predef.println(`x₂`)))
+Optimized: ls.foreach[scala.Any](((x: scala.Int) => if (((`x₂`: scala.Int) => `x₂`.<(3)).apply(x)) ((`x₃`: scala.Int) => scala.Predef.println(`x₃`)).apply(x) else ()))
 Result: ()
 
 Original: ls.map[scala.Long](((a: scala.Int) => a.toLong)).map[java.lang.String](((b: scala.Long) => b.toString()))

tests/run-staging/i3876-c.check

@@ -2,7 +2,7 @@
 {
   val f: scala.Function1[scala.Int, scala.Int] {
     def apply(x: scala.Int): scala.Int
-  } = ((x: scala.Int) => x.+(x))
+  } = ((`x₂`: scala.Int) => `x₂`.+(`x₂`))
 
   (f: scala.Function1[scala.Int, scala.Int] {
     def apply(x: scala.Int): scala.Int

tests/run-staging/i5144.check

@@ -1,4 +1,4 @@
 {
-  def f(x: scala.Int): scala.Int = ((x: scala.Int) => f(x)).apply(42)
+  def f(x: scala.Int): scala.Int = ((`x₂`: scala.Int) => f(`x₂`)).apply(42)
   ()
-}
+}

tests/run-staging/i8585.check

@@ -0,0 +1,22 @@
+The following would not compile:
+((x: scala.Double) => {
+  val y: scala.Double = x.*(x)
+  val `y₂`: scala.Double = y.*(y)
+  `y₂`.*(`y₂`)
+})
+3^8 = 6561.0
+The following would not compile:
+((x: scala.Double) => x.*({
+  val y: scala.Double = x.*(x)
+  y.*({
+    val `y₂`: scala.Double = y.*(y)
+    `y₂`.*({
+      val `y₃`: scala.Double = `y₂`.*(`y₂`)
+      `y₃`.*({
+        val `y₄`: scala.Double = `y₃`.*(`y₃`)
+        `y₄`.*(`y₄`)
+      })
+    })
+  })
+}))
+2^47 = 1.40737488355328E14

tests/run-staging/i8585.scala

@@ -0,0 +1,27 @@
+import scala.quoted._
+import scala.quoted.staging.{run, withQuoteContext, Toolbox}
+
+object Test {
+  given Toolbox = Toolbox.make(getClass.getClassLoader)
+
+  def main(args: Array[String]): Unit = {
+    val toTheEighth = stagedPower(8)
+    println("3^8 = " + toTheEighth(3))
+
+    val toThe47 = stagedPower(47)
+    println("2^47 = " + toThe47(2))
+  }
+
+  def stagedPower(n: Int): Double => Double = {
+    def code(using QuoteContext) = '{ (x: Double) => ${ powerCode(n, 'x) } }
+    println("The following would not compile:")
+    println(withQuoteContext(code.show))
+    run(code)
+  }
+
+  def powerCode(n: Int, x: Expr[Double])(using ctx: QuoteContext): Expr[Double] =
+    if (n == 1) x
+    else if (n == 2) '{ $x * $x }
+    else if (n % 2 == 1)  '{ $x * ${ powerCode(n - 1, x) } }
+    else '{ val y = $x * $x; ${ powerCode(n / 2, 'y) } }
+}

tests/run-staging/quote-run-2.check

@@ -11,11 +11,11 @@
 {
   val y: scala.Double = 5.0.*(5.0)
   y.*({
-    val y: scala.Double = y.*(y)
-    y.*({
-      val y: scala.Double = y.*(y)
-      val y: scala.Double = y.*(y)
-      y
+    val `y₂`: scala.Double = y.*(y)
+    `y₂`.*({
+      val `y₃`: scala.Double = `y₂`.*(`y₂`)
+      val `y₄`: scala.Double = `y₃`.*(`y₃`)
+      `y₄`
     })
   })
 }

tests/run-staging/quote-unrolled-foreach.check

@@ -33,7 +33,7 @@
   var i: scala.Int = 0
   while (i.<(size)) {
     val element: scala.Int = arr.apply(i)
-    ((i: scala.Int) => java.lang.System.out.println(i)).apply(element)
+    ((`i₂`: scala.Int) => java.lang.System.out.println(`i₂`)).apply(element)
     i = i.+(1)
   }
 })