test/typeparam: add a test case for issue48617

For #48617

Change-Id: I6c00b7912c441ac323a0adede63b7d4a9ae6f92d
Reviewed-on: https://go-review.googlesource.com/c/go/+/351858
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Dan Scales <danscales@google.com>
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Trust: Dan Scales <danscales@google.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>

1 files changed, 29 insertions, 0 deletions

diff --git a/test/typeparam/issue48617.go b/test/typeparam/issue48617.go
new file mode 100644
index 0000000000..4b00570ba6
--- /dev/null
+++ b/test/typeparam/issue48617.go
@@ -0,0 +1,29 @@
+// 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
+
+type Foo[T any] interface {
+	CreateBar() Bar[T]
+}
+
+type Bar[T any] func() Bar[T]
+
+func (f Bar[T]) CreateBar() Bar[T] {
+	return f
+}
+
+func abc[T any]() {
+	var b Bar[T] = func() Bar[T] {
+		var b Bar[T]
+		return b
+	}
+	var _ Foo[T] = b()
+}
+
+func main() {
+	abc[int]()
+}