Add paramSymss to TASTy reflect

Author: nicolasstucki

compiler/src/dotty/tools/dotc/tastyreflect/ReflectionCompilerInterface.scala

@@ -1749,6 +1749,9 @@ class ReflectionCompilerInterface(val rootContext: core.Contexts.Context) extend
   private def isMethod(sym: Symbol)(using ctx: Context): Boolean =
     sym.isTerm && sym.is(Flags.Method) && !sym.isConstructor
 
+  def Symbol_paramSymss(self: Symbol)(using ctx: Context): (List[Symbol], List[List[Symbol]]) =
+    self.paramSymss
+
   def Symbol_caseFields(self: Symbol)(using ctx: Context): List[Symbol] =
     if (!self.isClass) Nil
     else self.asClass.paramAccessors.collect {

library/src/scala/tasty/Reflection.scala

@@ -2223,6 +2223,12 @@ class Reflection(private[scala] val internal: CompilerInterface) { self =>
     def methods(using ctx: Context): List[Symbol] =
       internal.Symbol_methods(sym)
 
+    /** A pair consistsing of type paremeter symbols and value parameter symbol lists
+     *  of this method definition, or (Nil, Nil) for other symbols.
+     */
+    def paramSymss(using ctx: Context): (List[Symbol], List[List[Symbol]]) =
+      internal.Symbol_paramSymss(sym)
+
     /** Fields of a case class type -- only the ones declared in primary constructor */
     def caseFields(using ctx: Context): List[Symbol] =
       internal.Symbol_caseFields(sym)

library/src/scala/tasty/reflect/CompilerInterface.scala

@@ -1305,6 +1305,11 @@ trait CompilerInterface {
   /** Get all non-private methods declared or inherited */
   def Symbol_methods(self: Symbol)(using ctx: Context): List[Symbol]
 
+  /** A pair consistsing of type paremeter symbols and value parameter symbol lists
+   *  of this method definition, or (Nil, Nil) for other symbols.
+   */
+  def Symbol_paramSymss(self: Symbol)(using ctx: Context): (List[Symbol], List[List[Symbol]])
+
   /** Fields of a case class type -- only the ones declared in primary constructor */
   def Symbol_caseFields(self: Symbol)(using ctx: Context): List[Symbol]
 

tests/run-macros/paramSymss.check

@@ -0,0 +1,28 @@
+sym: Test$.a
+tparams: List()
+vparamss: List()
+
+sym: Test$.b
+tparams: List()
+vparamss: List(List(Test$._$i))
+
+sym: Test$.c
+tparams: List()
+vparamss: List(List(Test$._$x), List(Test$._$y), List(Test$._$z))
+
+sym: Test$.d
+tparams: List(Test$._$T)
+vparamss: List()
+
+sym: Test$.c
+tparams: List(Test$._$T, Test$._$U)
+vparamss: List(List(Test$._$x, Test$._$x2), List(Test$._$y), List(Test$._$z))
+
+sym: Test.<init>
+tparams: List(Test._$T)
+vparamss: List(List(Test._$a))
+
+sym: Test.<init>
+tparams: List(Test._$T)
+vparamss: List(List(Test._$a, Test._$b))
+

tests/run-macros/paramSymss/Macro_1.scala

@@ -0,0 +1,14 @@
+import scala.quoted._
+
+inline def showParamSyms(inline x: Any): String =
+  ${ showParamSymsExpr('x) }
+
+def showParamSymsExpr(using QuoteContext)(x: Expr[Any]): Expr[String] =
+  val '{ $y: Any } = x // Drop Inlined not to access the symbol
+  val sym = y.unseal.symbol
+  val (tparams, vparamss) = sym.paramSymss
+  Expr(
+    s"""sym: ${sym.show}
+       |tparams: ${tparams.map(_.show)}
+       |vparamss: ${vparamss.map(_.map(_.show))}
+       |""".stripMargin)

tests/run-macros/paramSymss/Test_2.scala

@@ -0,0 +1,20 @@
+
+object Test {
+  def a: Unit = ()
+  def b(i: Int): Unit = ()
+  def c(x: Int)(y: String)(z: Boolean): Unit = ()
+  def d[T]: Unit = ()
+  def c[T, U](x: Int, x2: Int)(y: String)(z: Boolean): Unit = ()
+
+  def main(args: Array[String]) =
+    println(showParamSyms(a))
+    println(showParamSyms(b(1)))
+    println(showParamSyms(c(2)("")(true)))
+    println(showParamSyms(d[Int]))
+    println(showParamSyms(c[Int, Char](3, 4)("")(true)))
+    println(showParamSyms(new Test(1)))
+    println(showParamSyms(new Test(1, 2)))
+}
+
+class Test[T](a: T):
+    def this(a: Int, b: T) = this(b)