Add reflect Symbol.info

Author: nicolasstucki

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

@@ -2519,6 +2519,8 @@ class QuotesImpl private (using val ctx: Context) extends Quotes, QuoteUnpickler
         def name: String = self.denot.name.toString
         def fullName: String = self.denot.fullName.toString
 
+        def info: TypeRepr = self.denot.info
+
         def pos: Option[Position] =
           if self.exists then Some(self.sourcePos) else None
 

library/src/scala/quoted/Quotes.scala

@@ -3772,6 +3772,10 @@ trait Quotes { self: runtime.QuoteUnpickler & runtime.QuoteMatching =>
         /** The full name of this symbol up to the root package */
         def fullName: String
 
+        /** Type of the definition */
+        @experimental
+        def info: TypeRepr
+
         /** The position of this symbol */
         def pos: Option[Position]
 

tests/run-custom-args/tasty-inspector/stdlibExperimentalDefinitions.scala

@@ -76,6 +76,7 @@ val experimentalDefinitionInLibrary = Set(
   "scala.quoted.Quotes.reflectModule.SymbolModule.newClass",
   "scala.quoted.Quotes.reflectModule.SymbolModule.newUniqueMethod",
   "scala.quoted.Quotes.reflectModule.SymbolModule.newUniqueVal",
+  "scala.quoted.Quotes.reflectModule.SymbolMethods.info",
 
   // New APIs: Lightweight lazy vals. Can be stabilized in 3.3.0
   "scala.runtime.LazyVals$.Evaluating",

tests/run-macros/i11685/Macro_1.scala

@@ -0,0 +1,79 @@
+package test
+
+import scala.quoted.*
+
+trait Thing {
+  type Type
+}
+
+object MyMacro {
+
+  def isExpectedReturnType[R: Type](using Quotes): quotes.reflect.Symbol => Boolean = { method =>
+    import quotes.reflect.*
+
+    val expectedReturnType = TypeRepr.of[R]
+
+    method.tree match {
+      case DefDef(_,_,typedTree,_) =>
+          TypeRepr.of(using typedTree.tpe.asType) <:< expectedReturnType
+      case _ => false
+    }
+  }
+
+  ///TODO no overloads
+  def checkMethod[R: Type](using q: Quotes)(method: quotes.reflect.Symbol): Option[String] = {
+    val isExpectedReturnTypeFun = isExpectedReturnType[R]
+
+    Option.when(method.paramSymss.headOption.exists(_.exists(_.isType)))(s"Method ${method.name} has a generic type parameter, this is not supported") orElse
+      Option.when(!isExpectedReturnTypeFun(method))(s"Method ${method.name} has unexpected return type")
+  }
+
+  def definedMethodsInType[T: Type](using Quotes): List[quotes.reflect.Symbol] = {
+    import quotes.reflect.*
+
+    val tree = TypeTree.of[T]
+
+    for {
+      member <- tree.symbol.methodMembers
+      //is abstract method, not implemented
+      if member.flags.is(Flags.Deferred)
+
+      //TODO: is that public?
+      // TODO? if member.privateWithin
+      if !member.flags.is(Flags.Private)
+      if !member.flags.is(Flags.Protected)
+      if !member.flags.is(Flags.PrivateLocal)
+
+      if !member.isClassConstructor
+      if !member.flags.is(Flags.Synthetic)
+    } yield member
+  }
+
+  transparent inline def client[T, R](r: () => R): T = ${MyMacro.clientImpl[T, R]('r)}
+
+  def clientImpl[T: Type, R: Type](r: Expr[() => R])(using Quotes): Expr[T] = {
+    import quotes.reflect.*
+
+    val apiType = TypeRepr.of[T]
+    val tree = TypeTree.of[T]
+
+    val methods = definedMethodsInType[T]
+    val invalidMethods = methods.flatMap(checkMethod[R])
+    if (invalidMethods.nonEmpty) {
+      report.errorAndAbort(s"Invalid methods: ${invalidMethods.mkString(", ")}")
+    }
+
+    val className = "_Anon"
+    val parents = List(TypeTree.of[Object], TypeTree.of[T])
+
+    def decls(cls: Symbol): List[Symbol] = methods.map { method =>
+      Symbol.newMethod(cls, method.name, method.info, flags = Flags.EmptyFlags /*TODO: method.flags */, privateWithin = method.privateWithin.fold(Symbol.noSymbol)(_.typeSymbol))
+    }
+
+    val cls = Symbol.newClass(Symbol.spliceOwner, className, parents = parents.map(_.tpe), decls, selfType = None)
+    val body = cls.declaredMethods.map { method => DefDef(method, argss => Some('{${r}()}.asTerm)) }
+    val clsDef = ClassDef(cls, parents, body = body)
+    val newCls = Typed(Apply(Select(New(TypeIdent(cls)), cls.primaryConstructor), Nil), TypeTree.of[T])
+    Block(List(clsDef), newCls).asExprOf[T]
+  }
+}

tests/run-macros/i11685/Test_2.scala

@@ -0,0 +1,15 @@
+import test.MyMacro
+
+trait Command {
+  def run(): Int
+  def run2(foo: String): Int
+  def run3: Int
+}
+
+@main
+def Test = {
+  val myCommand: Command = MyMacro.client[Command, Int](() => 12)
+  println(myCommand.run()) // 12
+  println(myCommand.run2("test")) // 12
+  println(myCommand.run3) // 12
+}