Add optionless support

Author: Jentsch

compiler/src/dotty/tools/dotc/typer/Applications.scala

@@ -1387,7 +1387,11 @@ trait Applications extends Compatibility {
         // TODO: Maybe the 'reorder' method above can be reused, or be template
         if (bunchedArgs != Nil && argTypes != Nil) {
 
-          val typeInfoOfGetMethod = unapplyFn.tpe.widen.asInstanceOf[MethodType].resType.member(nme.get).info
+          val typeInfoOfGetMethod =
+            if unapplyFn.tpe.widen.asInstanceOf[MethodType].resType.member(nme.get).exists then
+              unapplyFn.tpe.widen.asInstanceOf[MethodType].resType.member(nme.get).info
+            else
+              unapplyFn.tpe.widen.asInstanceOf[MethodType].resType
 
           val names = typeInfoOfGetMethod
             .memberDenots(typeNameFilter, (name, buf) => if (name.toString == "Names") buf += typeInfoOfGetMethod.member(name).asSingleDenotation)

compiler/test/dotty/tools/dotc/NamedPatternMatching.scala

@@ -37,4 +37,11 @@ class NamedPatternMatching {
     ).checkExpectedErrors()
   }
 
+  @Test def executionTest: Unit = {
+    implicit val testGroup: TestGroup = TestGroup("runPos")
+    aggregateTests(
+      compileFile("tests/run/runNamedPatternMatching.scala", defaultOptions),
+    ).checkRuns()
+  }
+
 }

tests/run/runNamedPatternMatching.check

@@ -0,0 +1,3 @@
+Got name
+Got age
+Got city

tests/run/runNamedPatternMatching.scala

@@ -0,0 +1,24 @@
+object Test:
+
+  class User(val name: String, val age: Int, val city: String)
+
+  //TODO: Test this
+  object UserEx:
+    class UserExtractor(user: User) extends Product:
+      def _1 = println("Got name"); user.name
+      def _2 = println("Got age"); user.age
+      def _3 = println("Got city"); user.city
+
+      type Names = ("name", "age", "city")
+
+      // Members declared in scala.Equals
+      def canEqual(that: Any): Boolean = ???
+
+      // Members declared in scala.Product
+      def productArity: Int = ???
+      def productElement(n: Int): Any = ???
+
+    def unapply(user: User) = UserExtractor(user)
+
+  def main(args: Array[String]): Unit =
+    val UserEx(city = _, name = _) = User("Guy", 25, "Paris")