Introduce Path type intended for storing nested path in type level

chimney/src/main/scala-2/io/scalaland/chimney/internal/compiletime/ChimneyTypesPlatform.scala

@@ -174,7 +174,6 @@ private[compiletime] trait ChimneyTypesPlatform extends ChimneyTypes { this: Chi
         def apply[F <: runtime.PatcherFlags.Flag: Type, Flags <: runtime.PatcherFlags: Type]
             : Type[runtime.PatcherFlags.Enable[F, Flags]] =
           weakTypeTag[runtime.PatcherFlags.Enable[F, Flags]]
-
         def unapply[A](A: Type[A]): Option[(?<[runtime.PatcherFlags.Flag], ?<[runtime.PatcherFlags])] =
           if (A.isCtor[runtime.PatcherFlags.Enable[?, ?]])
             Some(A.param_<[runtime.PatcherFlags.Flag](0) -> A.param_<[runtime.PatcherFlags](1))
@@ -184,7 +183,6 @@ private[compiletime] trait ChimneyTypesPlatform extends ChimneyTypes { this: Chi
         def apply[F <: runtime.PatcherFlags.Flag: Type, Flags <: runtime.PatcherFlags: Type]
             : Type[runtime.PatcherFlags.Disable[F, Flags]] =
           weakTypeTag[runtime.PatcherFlags.Disable[F, Flags]]
-
         def unapply[A](A: Type[A]): Option[(?<[runtime.PatcherFlags.Flag], ?<[runtime.PatcherFlags])] =
           if (A.isCtor[runtime.PatcherFlags.Disable[?, ?]])
             Some(A.param_<[runtime.PatcherFlags.Flag](0) -> A.param_<[runtime.PatcherFlags](1))
@@ -199,5 +197,23 @@ private[compiletime] trait ChimneyTypesPlatform extends ChimneyTypes { this: Chi
         val MacrosLogging: Type[runtime.PatcherFlags.MacrosLogging] = weakTypeTag[runtime.PatcherFlags.MacrosLogging]
       }
     }
+
+    object Path extends PathModule {
+      val Root: Type[runtime.Path.Root] = weakTypeTag[runtime.Path.Root]
+      object Select extends SelectModule {
+        def apply[Name <: String: Type, Instance <: runtime.Path: Type]: Type[runtime.Path.Select[Name, Instance]] =
+          weakTypeTag[runtime.Path.Select[Name, Instance]]
+        def unapply[A](A: Type[A]): Option[(?<[String], ?<[runtime.Path])] =
+          if (A.isCtor[runtime.Path.Select[?, ?]]) Some(A.param_<[String](0) -> A.param_<[runtime.Path](1))
+          else scala.None
+      }
+      object Match extends MatchModule {
+        def apply[Subtype: Type, Instance <: runtime.Path: Type]: Type[runtime.Path.Match[Subtype, Instance]] =
+          weakTypeTag[runtime.Path.Match[Subtype, Instance]]
+        def unapply[A](A: Type[A]): Option[(??, ?<[runtime.Path])] =
+          if (A.isCtor[runtime.Path.Match[?, ?]]) Some(A.param(0) -> A.param_<[runtime.Path](1))
+          else scala.None
+      }
+    }
   }
 }

chimney/src/main/scala-3/io/scalaland/chimney/internal/compiletime/ChimneyTypesPlatform.scala

@@ -200,5 +200,25 @@ private[compiletime] trait ChimneyTypesPlatform extends ChimneyTypes { this: Chi
         val MacrosLogging: Type[runtime.PatcherFlags.MacrosLogging] = quoted.Type.of[runtime.PatcherFlags.MacrosLogging]
       }
     }
+
+    object Path extends PathModule {
+      val Root: Type[runtime.Path.Root] = quoted.Type.of[runtime.Path.Root]
+      object Select extends SelectModule {
+        def apply[Name <: String: Type, Instance <: runtime.Path: Type]: Type[runtime.Path.Select[Name, Instance]] =
+          quoted.Type.of[runtime.Path.Select[Name, Instance]]
+        def unapply[A](tpe: Type[A]): Option[(?<[String], ?<[runtime.Path])] = tpe match
+          case '[runtime.Path.Select[name, instance]] =>
+            Some((Type[name].as_?<[String], Type[instance].as_?<[runtime.Path]))
+          case _ => scala.None
+      }
+      object Match extends MatchModule {
+        def apply[Subtype: Type, Instance <: runtime.Path: Type]: Type[runtime.Path.Match[Subtype, Instance]] =
+          quoted.Type.of[runtime.Path.Match[Subtype, Instance]]
+        def unapply[A](tpe: Type[A]): Option[(??, ?<[runtime.Path])] = tpe match
+          case '[runtime.Path.Match[subtype, instance]] =>
+            Some((Type[subtype].as_??, Type[instance].as_?<[runtime.Path]))
+          case _ => scala.None
+      }
+    }
   }
 }

chimney/src/main/scala/io/scalaland/chimney/internal/compiletime/ChimneyTypes.scala

@@ -171,6 +171,25 @@ private[compiletime] trait ChimneyTypes { this: ChimneyDefinitions =>
       }
     }
 
+    val Path: PathModule
+    trait PathModule { this: Path.type =>
+      val Root: Type[runtime.Path.Root]
+      val Select: SelectModule
+      trait SelectModule
+          extends Type.Ctor2UpperBounded[
+            String,
+            runtime.Path,
+            runtime.Path.Select
+          ] { this: Select.type => }
+      val Match: MatchModule
+      trait MatchModule
+          extends Type.Ctor2UpperBounded[
+            Any,
+            runtime.Path,
+            runtime.Path.Match
+          ] { this: Match.type => }
+    }
+
     // You can `import ChimneyType.Implicits.*` in your shared code to avoid providing types manually, while avoiding conflicts
     // with implicit types seen in platform-specific scopes (which would happen if those implicits were always used).
     object Implicits {

chimney/src/main/scala/io/scalaland/chimney/internal/runtime/Path.scala

@@ -0,0 +1,8 @@
+package io.scalaland.chimney.internal.runtime
+
+sealed abstract class Path
+object Path {
+  final class Root extends Path
+  final class Select[Name <: String, Instance <: Path] extends Path
+  final class Match[Subtype, Instance <: Path] extends Path
+}