Imported Upstream version 3.12.0

Former-commit-id: cf92446697332992ec36726e78eb8703e1f259d7

mcs/tests/test-pattern-05.cs

@@ -0,0 +1,39 @@
+// Compiler options: -langversion:experimental
+
+using System;
+
+class RecursiveNamedPattern
+{
+	public static int Main ()
+	{
+		object o = new C ();
+		bool b = o is C (name2: "", name1: -2);
+		if (b)
+			return 1;
+
+		b = o is C (name2: "n2", name1: -2);
+		if (!b)
+			return 2;
+
+		b = o is C ();
+		if (b)
+			return 3;
+
+		return 0;
+	}
+}
+
+class C
+{
+	public static bool operator is (C c, out long name1, out string name2)
+	{
+		name1 = -2;
+		name2 = "n2";
+		return true;
+	}
+
+	public static bool operator is (C c)
+	{
+		return false;
+	}
+}