blob: 4fcd85e693e9f4fe8514c8398494c7dc1bf0e5ae [file] [log] [blame]
// 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"
"os"
"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 os.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 != os.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 != os.EOF {
t.Errorf("Copyn(bytes.Buffer, foo, 4) = %d, %v; want 3, EOF", n, err)
}
}
func TestReadAtLeast(t *testing.T) {
var rb bytes.Buffer
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 != os.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)
}
}