1 // Copyright 2010 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 io_test 6 7 import ( 8 "bytes" 9 "crypto/sha1" 10 "fmt" 11 . "io" 12 "io/ioutil" 13 "strings" 14 "testing" 15 ) 16 17 func TestMultiReader(t *testing.T) { 18 var mr Reader 19 var buf []byte 20 nread := 0 21 withFooBar := func(tests func()) { 22 r1 := strings.NewReader("foo ") 23 r2 := strings.NewReader("") 24 r3 := strings.NewReader("bar") 25 mr = MultiReader(r1, r2, r3) 26 buf = make([]byte, 20) 27 tests() 28 } 29 expectRead := func(size int, expected string, eerr error) { 30 nread++ 31 n, gerr := mr.Read(buf[0:size]) 32 if n != len(expected) { 33 t.Errorf("#%d, expected %d bytes; got %d", 34 nread, len(expected), n) 35 } 36 got := string(buf[0:n]) 37 if got != expected { 38 t.Errorf("#%d, expected %q; got %q", 39 nread, expected, got) 40 } 41 if gerr != eerr { 42 t.Errorf("#%d, expected error %v; got %v", 43 nread, eerr, gerr) 44 } 45 buf = buf[n:] 46 } 47 withFooBar(func() { 48 expectRead(2, "fo", nil) 49 expectRead(5, "o ", nil) 50 expectRead(5, "bar", nil) 51 expectRead(5, "", EOF) 52 }) 53 withFooBar(func() { 54 expectRead(4, "foo ", nil) 55 expectRead(1, "b", nil) 56 expectRead(3, "ar", nil) 57 expectRead(1, "", EOF) 58 }) 59 withFooBar(func() { 60 expectRead(5, "foo ", nil) 61 }) 62 } 63 64 func TestMultiWriter(t *testing.T) { 65 sha1 := sha1.New() 66 sink := new(bytes.Buffer) 67 mw := MultiWriter(sha1, sink) 68 69 sourceString := "My input text." 70 source := strings.NewReader(sourceString) 71 written, err := Copy(mw, source) 72 73 if written != int64(len(sourceString)) { 74 t.Errorf("short write of %d, not %d", written, len(sourceString)) 75 } 76 77 if err != nil { 78 t.Errorf("unexpected error: %v", err) 79 } 80 81 sha1hex := fmt.Sprintf("%x", sha1.Sum(nil)) 82 if sha1hex != "01cb303fa8c30a64123067c5aa6284ba7ec2d31b" { 83 t.Error("incorrect sha1 value") 84 } 85 86 if sink.String() != sourceString { 87 t.Errorf("expected %q; got %q", sourceString, sink.String()) 88 } 89 } 90 91 // Test that MultiReader copies the input slice and is insulated from future modification. 92 func TestMultiReaderCopy(t *testing.T) { 93 slice := []Reader{strings.NewReader("hello world")} 94 r := MultiReader(slice...) 95 slice[0] = nil 96 data, err := ioutil.ReadAll(r) 97 if err != nil || string(data) != "hello world" { 98 t.Errorf("ReadAll() = %q, %v, want %q, nil", data, err, "hello world") 99 } 100 } 101 102 // Test that MultiWriter copies the input slice and is insulated from future modification. 103 func TestMultiWriterCopy(t *testing.T) { 104 var buf bytes.Buffer 105 slice := []Writer{&buf} 106 w := MultiWriter(slice...) 107 slice[0] = nil 108 n, err := w.Write([]byte("hello world")) 109 if err != nil || n != 11 { 110 t.Errorf("Write(`hello world`) = %d, %v, want 11, nil", n, err) 111 } 112 if buf.String() != "hello world" { 113 t.Errorf("buf.String() = %q, want %q", buf.String(), "hello world") 114 } 115 } 116
