airframe-surface: Scala3 higher-kind type support (#2395)

airframe=surface: Scala3 higher-kind type support
wvlet · Sep 5, 2022 · a1ce684 · a1ce684
1 parent ab39f24
commit a1ce684
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Showing 2 changed files with 19 additions and 24 deletions.
diff --git a/airframe-surface/src/main/scala-3/wvlet/airframe/surface/CompileTimeSurfaceFactory.scala b/airframe-surface/src/main/scala-3/wvlet/airframe/surface/CompileTimeSurfaceFactory.scala
@@ -1,6 +1,5 @@
 package wvlet.airframe.surface
 import scala.quoted._
-import dotty.tools.dotc.core.{Types as DottyTypes}
 
 private[surface] object CompileTimeSurfaceFactory {
 
@@ -91,19 +90,23 @@ private[surface] class CompileTimeSurfaceFactory[Q <: Quotes](using quotes: Q) {
     } else {
       seen += t
       // For debugging
-      // println(s"[${typeNameOf(t)}]\n  ${t}")
+      // println(s"[${typeNameOf(t)}]\n  ${t}\nfull type name: ${fullTypeNameOf(t)}\nclass: ${t.getClass}")
       val generator = factory.andThen { expr =>
-        val cacheKey =
-          if (typeNameOf(t) == "scala.Any" && classOf[DottyTypes.TypeBounds].isAssignableFrom(t.getClass)) {
-            // Distinguish scala.Any and type bounds (such as _)
-            s"${fullTypeNameOf(t)} for ${t}"
-          } else if (typeNameOf(t) == "scala.Any" && classOf[DottyTypes.TypeParamRef].isAssignableFrom(t.getClass)) {
-            // This ensure different cache key for each Type Parameter (such as T and U).
-            // This is required because fullTypeNameOf of every Type Parameters is `scala.Any`.
-            s"${fullTypeNameOf(t)} for ${t}"
-          } else {
-            fullTypeNameOf(t)
+        val cacheKey = if (typeNameOf(t) == "scala.Any") {
+          t match {
+            case ParamRef(TypeLambda(typeNames, _, _), _) =>
+              // Distinguish scala.Any and type bounds (such as _)
+              s"${fullTypeNameOf(t)} for ${t}"
+            case TypeBounds(_, _) =>
+              // This ensures different cache key for each Type Parameter (such as T and U).
+              // This is required because fullTypeNameOf of every Type Parameters is `scala.Any`.
+              s"${fullTypeNameOf(t)} for ${t}"
+            case _ =>
+              fullTypeNameOf(t)
           }
+        } else {
+          fullTypeNameOf(t)
+        }
         '{
           val key = ${ Expr(cacheKey) }
           if (!wvlet.airframe.surface.surfaceCache.contains(key)) {
@@ -130,7 +133,6 @@ private[surface] class CompileTimeSurfaceFactory[Q <: Quotes](using quotes: Q) {
       javaEnumFactory orElse
       exisitentialTypeFactory orElse
       genericTypeWithConstructorFactory orElse
-      typeParameterFactory orElse
       genericTypeFactory
   }
 
@@ -208,15 +210,16 @@ private[surface] class CompileTimeSurfaceFactory[Q <: Quotes](using quotes: Q) {
       val args     = a.args.map(surfaceOf(_))
       // TODO support type erasure instead of using AnyRefSurface
       '{ HigherKindedTypeSurface(${ Expr(name) }, ${ Expr(fullName) }, AnyRefSurface, ${ Expr.ofSeq(args) }) }
+    case p @ ParamRef(TypeLambda(typeNames, _, _), _) =>
+      val name     = typeNames.mkString(",")
+      val fullName = fullTypeNameOf(p)
+      '{ HigherKindedTypeSurface(${ Expr(name) }, ${ Expr(fullName) }, AnyRefSurface, Seq.empty) }
   }
 
   private def typeArgsOf(t: TypeRepr): List[TypeRepr] = {
     t match {
       case a: AppliedType =>
         a.args
-      // TODO: Dealiasing should be done before ?
-      case DottyTypes.TypeAlias(DottyTypes.HKTypeLambda(_, a: AppliedType)) =>
-        a.args
       case other =>
         List.empty
     }
@@ -401,12 +404,6 @@ private[surface] class CompileTimeSurfaceFactory[Q <: Quotes](using quotes: Q) {
     })
   }
 
-  private def typeParameterFactory: Factory = {
-    case p: DottyTypes.ParamRef if (fullTypeNameOf(p) == "Any") =>
-      val paramName = Expr(p.paramName.toString)
-      '{ HigherKindedTypeSurface(${ paramName }, ${ paramName }, AnyRefSurface, Nil) }
-  }
-
   private def genericTypeFactory: Factory = {
     case a: AppliedType =>
       val typeArgs = a.args.map(surfaceOf(_))

diff --git a/airframe-surface/src/test/scala/wvlet/airframe/surface/RecursiveHigherKindTypeTest.scala b/airframe-surface/src/test/scala/wvlet/airframe/surface/RecursiveHigherKindTypeTest.scala
@@ -37,8 +37,6 @@ class RecursiveHigherKindTypeTest extends SurfaceSpec {
   import Holder.BySkinny
 
   test("support recursive higher kind types") {
-    // ....
-
     val s = Surface.of[Holder[BySkinny]]
     assertEquals(s.name, "Holder[BySkinny]")
     assertEquals(s.isAlias, false)