1// Copyright 2020 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5package iotest_test
6
7import (
8	"errors"
9	"fmt"
10	"testing/iotest"
11)
12
13func ExampleErrReader() {
14	// A reader that always returns a custom error.
15	r := iotest.ErrReader(errors.New("custom error"))
16	n, err := r.Read(nil)
17	fmt.Printf("n:   %d\nerr: %q\n", n, err)
18
19	// Output:
20	// n:   0
21	// err: "custom error"
22}
23