1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
|
// Copyright 2009 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 io_test
import (
"bytes"
. "io"
"strings"
"testing"
)
// An version of bytes.Buffer without ReadFrom and WriteTo
type Buffer struct {
bytes.Buffer
ReaderFrom // conflicts with and hides bytes.Buffer's ReaderFrom.
WriterTo // conflicts with and hides bytes.Buffer's WriterTo.
}
// Simple tests, primarily to verify the ReadFrom and WriteTo callouts inside Copy and CopyN.
func TestCopy(t *testing.T) {
rb := new(Buffer)
wb := new(Buffer)
rb.WriteString("hello, world.")
Copy(wb, rb)
if wb.String() != "hello, world." {
t.Errorf("Copy did not work properly")
}
}
func TestCopyReadFrom(t *testing.T) {
rb := new(Buffer)
wb := new(bytes.Buffer) // implements ReadFrom.
rb.WriteString("hello, world.")
Copy(wb, rb)
if wb.String() != "hello, world." {
t.Errorf("Copy did not work properly")
}
}
func TestCopyWriteTo(t *testing.T) {
rb := new(bytes.Buffer) // implements WriteTo.
wb := new(Buffer)
rb.WriteString("hello, world.")
Copy(wb, rb)
if wb.String() != "hello, world." {
t.Errorf("Copy did not work properly")
}
}
func TestCopyN(t *testing.T) {
rb := new(Buffer)
wb := new(Buffer)
rb.WriteString("hello, world.")
CopyN(wb, rb, 5)
if wb.String() != "hello" {
t.Errorf("CopyN did not work properly")
}
}
func TestCopyNReadFrom(t *testing.T) {
rb := new(Buffer)
wb := new(bytes.Buffer) // implements ReadFrom.
rb.WriteString("hello")
CopyN(wb, rb, 5)
if wb.String() != "hello" {
t.Errorf("CopyN did not work properly")
}
}
func TestCopyNWriteTo(t *testing.T) {
rb := new(bytes.Buffer) // implements WriteTo.
wb := new(Buffer)
rb.WriteString("hello, world.")
CopyN(wb, rb, 5)
if wb.String() != "hello" {
t.Errorf("CopyN did not work properly")
}
}
type noReadFrom struct {
w Writer
}
func (w *noReadFrom) Write(p []byte) (n int, err error) {
return w.w.Write(p)
}
func TestCopyNEOF(t *testing.T) {
// Test that EOF behavior is the same regardless of whether
// argument to CopyN has ReadFrom.
b := new(bytes.Buffer)
n, err := CopyN(&noReadFrom{b}, strings.NewReader("foo"), 3)
if n != 3 || err != nil {
t.Errorf("CopyN(noReadFrom, foo, 3) = %d, %v; want 3, nil", n, err)
}
n, err = CopyN(&noReadFrom{b}, strings.NewReader("foo"), 4)
if n != 3 || err != EOF {
t.Errorf("CopyN(noReadFrom, foo, 4) = %d, %v; want 3, EOF", n, err)
}
n, err = CopyN(b, strings.NewReader("foo"), 3) // b has read from
if n != 3 || err != nil {
t.Errorf("CopyN(bytes.Buffer, foo, 3) = %d, %v; want 3, nil", n, err)
}
n, err = CopyN(b, strings.NewReader("foo"), 4) // b has read from
if n != 3 || err != EOF {
t.Errorf("CopyN(bytes.Buffer, foo, 4) = %d, %v; want 3, EOF", n, err)
}
}
func TestReadAtLeast(t *testing.T) {
var rb bytes.Buffer
testReadAtLeast(t, &rb)
}
// A version of bytes.Buffer that returns n > 0, EOF on Read
// when the input is exhausted.
type dataAndEOFBuffer struct {
bytes.Buffer
}
func (r *dataAndEOFBuffer) Read(p []byte) (n int, err error) {
n, err = r.Buffer.Read(p)
if n > 0 && r.Buffer.Len() == 0 && err == nil {
err = EOF
}
return
}
func TestReadAtLeastWithDataAndEOF(t *testing.T) {
var rb dataAndEOFBuffer
testReadAtLeast(t, &rb)
}
func testReadAtLeast(t *testing.T, rb ReadWriter) {
rb.Write([]byte("0123"))
buf := make([]byte, 2)
n, err := ReadAtLeast(rb, buf, 2)
if err != nil {
t.Error(err)
}
n, err = ReadAtLeast(rb, buf, 4)
if err != ErrShortBuffer {
t.Errorf("expected ErrShortBuffer got %v", err)
}
if n != 0 {
t.Errorf("expected to have read 0 bytes, got %v", n)
}
n, err = ReadAtLeast(rb, buf, 1)
if err != nil {
t.Error(err)
}
if n != 2 {
t.Errorf("expected to have read 2 bytes, got %v", n)
}
n, err = ReadAtLeast(rb, buf, 2)
if err != EOF {
t.Errorf("expected EOF, got %v", err)
}
if n != 0 {
t.Errorf("expected to have read 0 bytes, got %v", n)
}
rb.Write([]byte("4"))
n, err = ReadAtLeast(rb, buf, 2)
if err != ErrUnexpectedEOF {
t.Errorf("expected ErrUnexpectedEOF, got %v", err)
}
if n != 1 {
t.Errorf("expected to have read 1 bytes, got %v", n)
}
}
func TestTeeReader(t *testing.T) {
src := []byte("hello, world")
dst := make([]byte, len(src))
rb := bytes.NewBuffer(src)
wb := new(bytes.Buffer)
r := TeeReader(rb, wb)
if n, err := ReadFull(r, dst); err != nil || n != len(src) {
t.Fatalf("ReadFull(r, dst) = %d, %v; want %d, nil", n, err, len(src))
}
if !bytes.Equal(dst, src) {
t.Errorf("bytes read = %q want %q", dst, src)
}
if !bytes.Equal(wb.Bytes(), src) {
t.Errorf("bytes written = %q want %q", wb.Bytes(), src)
}
if n, err := r.Read(dst); n != 0 || err != EOF {
t.Errorf("r.Read at EOF = %d, %v want 0, EOF", n, err)
}
rb = bytes.NewBuffer(src)
pr, pw := Pipe()
pr.Close()
r = TeeReader(rb, pw)
if n, err := ReadFull(r, dst); n != 0 || err != ErrClosedPipe {
t.Errorf("closed tee: ReadFull(r, dst) = %d, %v; want 0, EPIPE", n, err)
}
}
|
