github.com/shogo82148/std@v1.22.1-0.20240327122250-4e474527810c/testing/iotest/example_test.go (about)

     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  
     5  package iotest_test
     6  
     7  import (
     8  	"github.com/shogo82148/std/errors"
     9  	"github.com/shogo82148/std/fmt"
    10  	"github.com/shogo82148/std/testing/iotest"
    11  )
    12  
    13  func ExampleErrReader() {
    14  	// 常にカスタムエラーを返すリーダー。
    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  }