Add quoted pattern type variable expected type test

Author: mbovel

tests/neg-macros/i22616b.check

@@ -0,0 +1,13 @@
+-- [E007] Type Mismatch Error: tests/neg-macros/i22616b.scala:17:18 ----------------------------------------------------
+17 |      case '{ Foo($y: t) } => // error
+   |                  ^^^^^
+   |                  Found:    t
+   |                  Required: String
+   |
+   | longer explanation available when compiling with `-explain`
+-- [E006] Not Found Error: tests/neg-macros/i22616b.scala:18:19 --------------------------------------------------------
+18 |        '{type S = t; ()} // error
+   |                   ^
+   |                   Not found: type t
+   |
+   | longer explanation available when compiling with `-explain`

tests/neg-macros/i22616b.scala

@@ -0,0 +1,22 @@
+// This test illustrates a current limitation of quoted pattern type variables,
+// which has been discussed in https://github.com/scala/scala3/issues/22616#issuecomment-3012534064:
+// These type variables do not have bound in general (see `typedQuotedTypeVar`),
+// so they might not conform to the expected type. Here, `t` does not conform
+// to `String`.
+
+import scala.quoted.{FromExpr, Expr, Quotes}
+
+case class Foo(x: String)
+
+object Macro:
+  inline def myMacro(): Unit =
+    ${ myMacroImpl('{Foo("hello")}) }
+
+  def myMacroImpl(x: Expr[Foo])(using Quotes): Expr[Unit] =
+    x match
+      case '{ Foo($y: t) } => // error
+        '{type S = t; ()} // error
+      case _ =>
+        println("not a foo")
+
+    '{()}