1 files changed, 37 insertions, 0 deletions
diff --git a/test/typeparam/typeswitch7.go b/test/typeparam/typeswitch7.go
new file mode 100644
index 0000000000..f2e1279fb4
--- /dev/null
+++ b/test/typeparam/typeswitch7.go
@@ -0,0 +1,37 @@
+// run -gcflags=-G=3
+
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+func f[T any](i interface{foo()}) {
+	switch i.(type) {
+	case interface{bar() T}:
+		println("barT")
+	case myint:
+		println("myint")
+	case myfloat:
+		println("myfloat")
+	default:
+		println("other")
+	}
+}
+
+type myint int
+func (myint) foo() {
+}
+func (x myint) bar() int {
+	return int(x)
+}
+
+type myfloat float64
+func (myfloat) foo() {
+}
+
+func main() {
+	f[int](nil)
+	f[int](myint(6))
+	f[int](myfloat(7))
+}