From 16b8660ea57bc1368d3a99dd37754d94f0a56fc9 Mon Sep 17 00:00:00 2001
From: Tom Grigg <tomegrigg@gmail.com>
Date: Mon, 30 May 2022 13:34:30 -0700
Subject: [PATCH] Add regression test for #15183

---
 tests/pos/i15183/decoder_1.scala | 14 ++++++++++++++
 tests/pos/i15183/test_2.scala    | 12 ++++++++++++
 2 files changed, 26 insertions(+)
 create mode 100644 tests/pos/i15183/decoder_1.scala
 create mode 100644 tests/pos/i15183/test_2.scala

diff --git a/tests/pos/i15183/decoder_1.scala b/tests/pos/i15183/decoder_1.scala
new file mode 100644
index 000000000000..532fd7246c3a
--- /dev/null
+++ b/tests/pos/i15183/decoder_1.scala
@@ -0,0 +1,14 @@
+import scala.deriving._
+
+sealed trait Decoder[T]
+object Decoder {
+  given Decoder[Double] = ???
+
+  inline given summonEmptyTuple[H]: Tuple.Map[EmptyTuple.type, Decoder] =
+    EmptyTuple
+
+  inline given summonTuple[H, T <: Tuple](using hd: Decoder[H], td: Tuple.Map[T, Decoder]): Tuple.Map[H *: T, Decoder] =
+    hd *: td
+
+  inline given derived[T](using m: Mirror.Of[T], d: Tuple.Map[m.MirroredElemTypes, Decoder]): Decoder[T] = ???
+}
diff --git a/tests/pos/i15183/test_2.scala b/tests/pos/i15183/test_2.scala
new file mode 100644
index 000000000000..2069d5637734
--- /dev/null
+++ b/tests/pos/i15183/test_2.scala
@@ -0,0 +1,12 @@
+// Fails in each cases below
+enum Env derives Decoder:
+  case Local,Sit,Prod
+
+enum Env2 derives Decoder:
+  case Local()
+  case Sit()
+  case Prod()
+
+enum Shape derives Decoder:
+  case Rectangle(width: Double, height: Double)
+  case Circle(radius: Double)