Fix #3050

Author: biboudis

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

@@ -58,7 +58,9 @@ class ReTyper extends Typer {
   }
 
   override def typedUnApply(tree: untpd.UnApply, selType: Type)(implicit ctx: Context): UnApply = {
-    val fun1 = typedExpr(tree.fun, AnyFunctionProto)
+    val funProto = new UnapplyFunProto(WildcardType, this)
+
+    val fun1 = typedExpr(tree.fun, funProto)
     val implicits1 = tree.implicits.map(typedExpr(_))
     val patterns1 = tree.patterns.mapconserve(pat => typed(pat, pat.tpe))
     untpd.cpy.UnApply(tree)(fun1, implicits1, patterns1).withType(tree.tpe)

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

@@ -2125,7 +2125,8 @@ class Typer extends Namer with TypeAssigner with Applications with Implicits wit
           tree match {
             case _: RefTree | _: Literal
             if !isVarPattern(tree) &&
-               !(tree.tpe <:< pt)(ctx.addMode(Mode.GADTflexible)) =>
+               !(tree.tpe <:< pt)(ctx.addMode(Mode.GADTflexible)) &&
+               !this.isInstanceOf[ReTyper] =>
               val cmp =
                 untpd.Apply(
                   untpd.Select(untpd.TypedSplice(tree), nme.EQ),

tests/pos/i3050.scala

@@ -0,0 +1,11 @@
+object Test {
+  inline def openImpl(): Int =
+    Some(42) match { case Some(i) => i }
+
+  def open(): Int = openImpl()
+
+  inline def openImpl2(): Int =
+    Some(42) match { case None => 42 }
+
+  def open2(): Int = openImpl2()
+}