1 files changed, 75 insertions, 0 deletions
diff --git a/test/typeparam/issue50486.dir/goerror_fp.go b/test/typeparam/issue50486.dir/goerror_fp.go
new file mode 100644
index 0000000..fec9095
--- /dev/null
+++ b/test/typeparam/issue50486.dir/goerror_fp.go
@@ -0,0 +1,75 @@
+// Copyright 2022 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 goerror_fp
+
+type Seq[T any] []T
+
+func (r Seq[T]) Size() int {
+	return len(r)
+}
+
+func (r Seq[T]) Append(items ...T) Seq[T] {
+	tail := Seq[T](items)
+	ret := make(Seq[T], r.Size()+tail.Size())
+
+	for i := range r {
+		ret[i] = r[i]
+	}
+
+	for i := range tail {
+		ret[i+r.Size()] = tail[i]
+	}
+
+	return ret
+}
+
+func (r Seq[T]) Iterator() Iterator[T] {
+	idx := 0
+
+	return Iterator[T]{
+		IsHasNext: func() bool {
+			return idx < r.Size()
+		},
+		GetNext: func() T {
+			ret := r[idx]
+			idx++
+			return ret
+		},
+	}
+}
+
+type Iterator[T any] struct {
+	IsHasNext func() bool
+	GetNext   func() T
+}
+
+func (r Iterator[T]) ToSeq() Seq[T] {
+	ret := Seq[T]{}
+	for r.HasNext() {
+		ret = append(ret, r.Next())
+	}
+	return ret
+}
+
+func (r Iterator[T]) Map(f func(T) any) Iterator[any] {
+	return MakeIterator(r.HasNext, func() any {
+		return f(r.Next())
+	})
+}
+
+func (r Iterator[T]) HasNext() bool {
+	return r.IsHasNext()
+}
+
+func (r Iterator[T]) Next() T {
+	return r.GetNext()
+}
+
+func MakeIterator[T any](has func() bool, next func() T) Iterator[T] {
+	return Iterator[T]{
+		IsHasNext: has,
+		GetNext:   next,
+	}
+}