1573 lines
40 KiB
Go
1573 lines
40 KiB
Go
// Copyright 2009 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package bufio_test
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import (
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. "bufio"
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"bytes"
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"errors"
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"fmt"
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"io"
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"io/ioutil"
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"strings"
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"testing"
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"testing/iotest"
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"time"
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"unicode/utf8"
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)
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// Reads from a reader and rot13s the result.
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type rot13Reader struct {
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r io.Reader
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}
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func newRot13Reader(r io.Reader) *rot13Reader {
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r13 := new(rot13Reader)
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r13.r = r
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return r13
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}
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func (r13 *rot13Reader) Read(p []byte) (int, error) {
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n, err := r13.r.Read(p)
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for i := 0; i < n; i++ {
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c := p[i] | 0x20 // lowercase byte
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if 'a' <= c && c <= 'm' {
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p[i] += 13
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} else if 'n' <= c && c <= 'z' {
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p[i] -= 13
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}
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}
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return n, err
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}
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// Call ReadByte to accumulate the text of a file
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func readBytes(buf *Reader) string {
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var b [1000]byte
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nb := 0
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for {
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c, err := buf.ReadByte()
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if err == io.EOF {
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break
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}
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if err == nil {
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b[nb] = c
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nb++
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} else if err != iotest.ErrTimeout {
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panic("Data: " + err.Error())
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}
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}
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return string(b[0:nb])
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}
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func TestReaderSimple(t *testing.T) {
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data := "hello world"
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b := NewReader(strings.NewReader(data))
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if s := readBytes(b); s != "hello world" {
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t.Errorf("simple hello world test failed: got %q", s)
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}
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b = NewReader(newRot13Reader(strings.NewReader(data)))
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if s := readBytes(b); s != "uryyb jbeyq" {
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t.Errorf("rot13 hello world test failed: got %q", s)
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}
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}
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type readMaker struct {
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name string
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fn func(io.Reader) io.Reader
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}
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var readMakers = []readMaker{
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{"full", func(r io.Reader) io.Reader { return r }},
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{"byte", iotest.OneByteReader},
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{"half", iotest.HalfReader},
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{"data+err", iotest.DataErrReader},
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{"timeout", iotest.TimeoutReader},
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}
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// Call ReadString (which ends up calling everything else)
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// to accumulate the text of a file.
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func readLines(b *Reader) string {
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s := ""
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for {
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s1, err := b.ReadString('\n')
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if err == io.EOF {
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break
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}
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if err != nil && err != iotest.ErrTimeout {
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panic("GetLines: " + err.Error())
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}
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s += s1
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}
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return s
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}
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// Call Read to accumulate the text of a file
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func reads(buf *Reader, m int) string {
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var b [1000]byte
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nb := 0
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for {
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n, err := buf.Read(b[nb : nb+m])
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nb += n
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if err == io.EOF {
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break
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}
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}
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return string(b[0:nb])
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}
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type bufReader struct {
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name string
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fn func(*Reader) string
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}
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var bufreaders = []bufReader{
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{"1", func(b *Reader) string { return reads(b, 1) }},
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{"2", func(b *Reader) string { return reads(b, 2) }},
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{"3", func(b *Reader) string { return reads(b, 3) }},
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{"4", func(b *Reader) string { return reads(b, 4) }},
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{"5", func(b *Reader) string { return reads(b, 5) }},
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{"7", func(b *Reader) string { return reads(b, 7) }},
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{"bytes", readBytes},
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{"lines", readLines},
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}
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const minReadBufferSize = 16
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var bufsizes = []int{
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0, minReadBufferSize, 23, 32, 46, 64, 93, 128, 1024, 4096,
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}
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func TestReader(t *testing.T) {
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var texts [31]string
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str := ""
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all := ""
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for i := 0; i < len(texts)-1; i++ {
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texts[i] = str + "\n"
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all += texts[i]
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str += string(i%26 + 'a')
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}
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texts[len(texts)-1] = all
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for h := 0; h < len(texts); h++ {
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text := texts[h]
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for i := 0; i < len(readMakers); i++ {
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for j := 0; j < len(bufreaders); j++ {
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for k := 0; k < len(bufsizes); k++ {
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readmaker := readMakers[i]
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bufreader := bufreaders[j]
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bufsize := bufsizes[k]
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read := readmaker.fn(strings.NewReader(text))
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buf := NewReaderSize(read, bufsize)
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s := bufreader.fn(buf)
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if s != text {
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t.Errorf("reader=%s fn=%s bufsize=%d want=%q got=%q",
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readmaker.name, bufreader.name, bufsize, text, s)
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}
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}
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}
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}
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}
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}
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type zeroReader struct{}
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func (zeroReader) Read(p []byte) (int, error) {
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return 0, nil
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}
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func TestZeroReader(t *testing.T) {
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var z zeroReader
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r := NewReader(z)
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c := make(chan error)
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go func() {
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_, err := r.ReadByte()
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c <- err
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}()
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select {
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case err := <-c:
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if err == nil {
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t.Error("error expected")
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} else if err != io.ErrNoProgress {
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t.Error("unexpected error:", err)
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}
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case <-time.After(time.Second):
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t.Error("test timed out (endless loop in ReadByte?)")
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}
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}
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// A StringReader delivers its data one string segment at a time via Read.
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type StringReader struct {
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data []string
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step int
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}
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func (r *StringReader) Read(p []byte) (n int, err error) {
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if r.step < len(r.data) {
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s := r.data[r.step]
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n = copy(p, s)
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r.step++
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} else {
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err = io.EOF
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}
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return
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}
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func readRuneSegments(t *testing.T, segments []string) {
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got := ""
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want := strings.Join(segments, "")
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r := NewReader(&StringReader{data: segments})
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for {
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r, _, err := r.ReadRune()
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if err != nil {
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if err != io.EOF {
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return
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}
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break
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}
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got += string(r)
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}
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if got != want {
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t.Errorf("segments=%v got=%s want=%s", segments, got, want)
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}
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}
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var segmentList = [][]string{
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{},
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{""},
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{"日", "本語"},
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{"\u65e5", "\u672c", "\u8a9e"},
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{"\U000065e5", "\U0000672c", "\U00008a9e"},
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{"\xe6", "\x97\xa5\xe6", "\x9c\xac\xe8\xaa\x9e"},
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{"Hello", ", ", "World", "!"},
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{"Hello", ", ", "", "World", "!"},
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}
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func TestReadRune(t *testing.T) {
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for _, s := range segmentList {
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readRuneSegments(t, s)
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}
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}
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func TestUnreadRune(t *testing.T) {
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segments := []string{"Hello, world:", "日本語"}
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r := NewReader(&StringReader{data: segments})
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got := ""
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want := strings.Join(segments, "")
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// Normal execution.
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for {
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r1, _, err := r.ReadRune()
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if err != nil {
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if err != io.EOF {
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t.Error("unexpected error on ReadRune:", err)
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}
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break
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}
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got += string(r1)
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// Put it back and read it again.
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if err = r.UnreadRune(); err != nil {
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t.Fatal("unexpected error on UnreadRune:", err)
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}
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r2, _, err := r.ReadRune()
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if err != nil {
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t.Fatal("unexpected error reading after unreading:", err)
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}
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if r1 != r2 {
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t.Fatalf("incorrect rune after unread: got %c, want %c", r1, r2)
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}
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}
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if got != want {
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t.Errorf("got %q, want %q", got, want)
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}
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}
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func TestUnreadByte(t *testing.T) {
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segments := []string{"Hello, ", "world"}
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r := NewReader(&StringReader{data: segments})
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got := ""
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want := strings.Join(segments, "")
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// Normal execution.
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for {
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b1, err := r.ReadByte()
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if err != nil {
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if err != io.EOF {
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t.Error("unexpected error on ReadByte:", err)
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}
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break
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}
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got += string(b1)
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// Put it back and read it again.
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if err = r.UnreadByte(); err != nil {
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t.Fatal("unexpected error on UnreadByte:", err)
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}
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b2, err := r.ReadByte()
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if err != nil {
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t.Fatal("unexpected error reading after unreading:", err)
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}
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if b1 != b2 {
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t.Fatalf("incorrect byte after unread: got %q, want %q", b1, b2)
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}
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}
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if got != want {
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t.Errorf("got %q, want %q", got, want)
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}
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}
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func TestUnreadByteMultiple(t *testing.T) {
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segments := []string{"Hello, ", "world"}
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data := strings.Join(segments, "")
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for n := 0; n <= len(data); n++ {
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r := NewReader(&StringReader{data: segments})
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// Read n bytes.
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for i := 0; i < n; i++ {
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b, err := r.ReadByte()
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if err != nil {
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t.Fatalf("n = %d: unexpected error on ReadByte: %v", n, err)
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}
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if b != data[i] {
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t.Fatalf("n = %d: incorrect byte returned from ReadByte: got %q, want %q", n, b, data[i])
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}
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}
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// Unread one byte if there is one.
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if n > 0 {
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if err := r.UnreadByte(); err != nil {
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t.Errorf("n = %d: unexpected error on UnreadByte: %v", n, err)
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}
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}
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// Test that we cannot unread any further.
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if err := r.UnreadByte(); err == nil {
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t.Errorf("n = %d: expected error on UnreadByte", n)
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}
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}
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}
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func TestUnreadByteOthers(t *testing.T) {
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// A list of readers to use in conjunction with UnreadByte.
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var readers = []func(*Reader, byte) ([]byte, error){
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(*Reader).ReadBytes,
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(*Reader).ReadSlice,
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func(r *Reader, delim byte) ([]byte, error) {
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data, err := r.ReadString(delim)
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return []byte(data), err
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},
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// ReadLine doesn't fit the data/pattern easily
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// so we leave it out. It should be covered via
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// the ReadSlice test since ReadLine simply calls
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// ReadSlice, and it's that function that handles
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// the last byte.
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}
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// Try all readers with UnreadByte.
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for rno, read := range readers {
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// Some input data that is longer than the minimum reader buffer size.
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const n = 10
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var buf bytes.Buffer
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for i := 0; i < n; i++ {
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buf.WriteString("abcdefg")
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}
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r := NewReaderSize(&buf, minReadBufferSize)
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readTo := func(delim byte, want string) {
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data, err := read(r, delim)
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if err != nil {
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t.Fatalf("#%d: unexpected error reading to %c: %v", rno, delim, err)
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}
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if got := string(data); got != want {
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t.Fatalf("#%d: got %q, want %q", rno, got, want)
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}
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}
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// Read the data with occasional UnreadByte calls.
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for i := 0; i < n; i++ {
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readTo('d', "abcd")
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for j := 0; j < 3; j++ {
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if err := r.UnreadByte(); err != nil {
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t.Fatalf("#%d: unexpected error on UnreadByte: %v", rno, err)
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}
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readTo('d', "d")
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}
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readTo('g', "efg")
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}
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// All data should have been read.
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_, err := r.ReadByte()
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if err != io.EOF {
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t.Errorf("#%d: got error %v; want EOF", rno, err)
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}
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}
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}
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// Test that UnreadRune fails if the preceding operation was not a ReadRune.
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func TestUnreadRuneError(t *testing.T) {
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buf := make([]byte, 3) // All runes in this test are 3 bytes long
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r := NewReader(&StringReader{data: []string{"日本語日本語日本語"}})
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if r.UnreadRune() == nil {
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t.Error("expected error on UnreadRune from fresh buffer")
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}
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_, _, err := r.ReadRune()
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if err != nil {
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t.Error("unexpected error on ReadRune (1):", err)
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}
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if err = r.UnreadRune(); err != nil {
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t.Error("unexpected error on UnreadRune (1):", err)
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}
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if r.UnreadRune() == nil {
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t.Error("expected error after UnreadRune (1)")
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}
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// Test error after Read.
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_, _, err = r.ReadRune() // reset state
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if err != nil {
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t.Error("unexpected error on ReadRune (2):", err)
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}
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_, err = r.Read(buf)
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if err != nil {
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t.Error("unexpected error on Read (2):", err)
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}
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if r.UnreadRune() == nil {
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t.Error("expected error after Read (2)")
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}
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// Test error after ReadByte.
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_, _, err = r.ReadRune() // reset state
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if err != nil {
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t.Error("unexpected error on ReadRune (2):", err)
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}
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for range buf {
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_, err = r.ReadByte()
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if err != nil {
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t.Error("unexpected error on ReadByte (2):", err)
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}
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}
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if r.UnreadRune() == nil {
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t.Error("expected error after ReadByte")
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}
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// Test error after UnreadByte.
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_, _, err = r.ReadRune() // reset state
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if err != nil {
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t.Error("unexpected error on ReadRune (3):", err)
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}
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_, err = r.ReadByte()
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if err != nil {
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t.Error("unexpected error on ReadByte (3):", err)
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}
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err = r.UnreadByte()
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if err != nil {
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t.Error("unexpected error on UnreadByte (3):", err)
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}
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if r.UnreadRune() == nil {
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t.Error("expected error after UnreadByte (3)")
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}
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// Test error after ReadSlice.
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_, _, err = r.ReadRune() // reset state
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if err != nil {
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t.Error("unexpected error on ReadRune (4):", err)
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}
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_, err = r.ReadSlice(0)
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if err != io.EOF {
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t.Error("unexpected error on ReadSlice (4):", err)
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}
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if r.UnreadRune() == nil {
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t.Error("expected error after ReadSlice (4)")
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}
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}
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func TestUnreadRuneAtEOF(t *testing.T) {
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// UnreadRune/ReadRune should error at EOF (was a bug; used to panic)
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r := NewReader(strings.NewReader("x"))
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r.ReadRune()
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r.ReadRune()
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r.UnreadRune()
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_, _, err := r.ReadRune()
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if err == nil {
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t.Error("expected error at EOF")
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} else if err != io.EOF {
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t.Error("expected EOF; got", err)
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}
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}
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func TestReadWriteRune(t *testing.T) {
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const NRune = 1000
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byteBuf := new(bytes.Buffer)
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w := NewWriter(byteBuf)
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// Write the runes out using WriteRune
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buf := make([]byte, utf8.UTFMax)
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for r := rune(0); r < NRune; r++ {
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size := utf8.EncodeRune(buf, r)
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nbytes, err := w.WriteRune(r)
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if err != nil {
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t.Fatalf("WriteRune(0x%x) error: %s", r, err)
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}
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if nbytes != size {
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t.Fatalf("WriteRune(0x%x) expected %d, got %d", r, size, nbytes)
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}
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}
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w.Flush()
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r := NewReader(byteBuf)
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// Read them back with ReadRune
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for r1 := rune(0); r1 < NRune; r1++ {
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size := utf8.EncodeRune(buf, r1)
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nr, nbytes, err := r.ReadRune()
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if nr != r1 || nbytes != size || err != nil {
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t.Fatalf("ReadRune(0x%x) got 0x%x,%d not 0x%x,%d (err=%s)", r1, nr, nbytes, r1, size, err)
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}
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}
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}
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|
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func TestWriter(t *testing.T) {
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var data [8192]byte
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for i := 0; i < len(data); i++ {
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data[i] = byte(' ' + i%('~'-' '))
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}
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w := new(bytes.Buffer)
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for i := 0; i < len(bufsizes); i++ {
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for j := 0; j < len(bufsizes); j++ {
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nwrite := bufsizes[i]
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bs := bufsizes[j]
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|
|
// Write nwrite bytes using buffer size bs.
|
|
// Check that the right amount makes it out
|
|
// and that the data is correct.
|
|
|
|
w.Reset()
|
|
buf := NewWriterSize(w, bs)
|
|
context := fmt.Sprintf("nwrite=%d bufsize=%d", nwrite, bs)
|
|
n, e1 := buf.Write(data[0:nwrite])
|
|
if e1 != nil || n != nwrite {
|
|
t.Errorf("%s: buf.Write %d = %d, %v", context, nwrite, n, e1)
|
|
continue
|
|
}
|
|
if e := buf.Flush(); e != nil {
|
|
t.Errorf("%s: buf.Flush = %v", context, e)
|
|
}
|
|
|
|
written := w.Bytes()
|
|
if len(written) != nwrite {
|
|
t.Errorf("%s: %d bytes written", context, len(written))
|
|
}
|
|
for l := 0; l < len(written); l++ {
|
|
if written[i] != data[i] {
|
|
t.Errorf("wrong bytes written")
|
|
t.Errorf("want=%q", data[0:len(written)])
|
|
t.Errorf("have=%q", written)
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Check that write errors are returned properly.
|
|
|
|
type errorWriterTest struct {
|
|
n, m int
|
|
err error
|
|
expect error
|
|
}
|
|
|
|
func (w errorWriterTest) Write(p []byte) (int, error) {
|
|
return len(p) * w.n / w.m, w.err
|
|
}
|
|
|
|
var errorWriterTests = []errorWriterTest{
|
|
{0, 1, nil, io.ErrShortWrite},
|
|
{1, 2, nil, io.ErrShortWrite},
|
|
{1, 1, nil, nil},
|
|
{0, 1, io.ErrClosedPipe, io.ErrClosedPipe},
|
|
{1, 2, io.ErrClosedPipe, io.ErrClosedPipe},
|
|
{1, 1, io.ErrClosedPipe, io.ErrClosedPipe},
|
|
}
|
|
|
|
func TestWriteErrors(t *testing.T) {
|
|
for _, w := range errorWriterTests {
|
|
buf := NewWriter(w)
|
|
_, e := buf.Write([]byte("hello world"))
|
|
if e != nil {
|
|
t.Errorf("Write hello to %v: %v", w, e)
|
|
continue
|
|
}
|
|
// Two flushes, to verify the error is sticky.
|
|
for i := 0; i < 2; i++ {
|
|
e = buf.Flush()
|
|
if e != w.expect {
|
|
t.Errorf("Flush %d/2 %v: got %v, wanted %v", i+1, w, e, w.expect)
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
func TestNewReaderSizeIdempotent(t *testing.T) {
|
|
const BufSize = 1000
|
|
b := NewReaderSize(strings.NewReader("hello world"), BufSize)
|
|
// Does it recognize itself?
|
|
b1 := NewReaderSize(b, BufSize)
|
|
if b1 != b {
|
|
t.Error("NewReaderSize did not detect underlying Reader")
|
|
}
|
|
// Does it wrap if existing buffer is too small?
|
|
b2 := NewReaderSize(b, 2*BufSize)
|
|
if b2 == b {
|
|
t.Error("NewReaderSize did not enlarge buffer")
|
|
}
|
|
}
|
|
|
|
func TestNewWriterSizeIdempotent(t *testing.T) {
|
|
const BufSize = 1000
|
|
b := NewWriterSize(new(bytes.Buffer), BufSize)
|
|
// Does it recognize itself?
|
|
b1 := NewWriterSize(b, BufSize)
|
|
if b1 != b {
|
|
t.Error("NewWriterSize did not detect underlying Writer")
|
|
}
|
|
// Does it wrap if existing buffer is too small?
|
|
b2 := NewWriterSize(b, 2*BufSize)
|
|
if b2 == b {
|
|
t.Error("NewWriterSize did not enlarge buffer")
|
|
}
|
|
}
|
|
|
|
func TestWriteString(t *testing.T) {
|
|
const BufSize = 8
|
|
buf := new(bytes.Buffer)
|
|
b := NewWriterSize(buf, BufSize)
|
|
b.WriteString("0") // easy
|
|
b.WriteString("123456") // still easy
|
|
b.WriteString("7890") // easy after flush
|
|
b.WriteString("abcdefghijklmnopqrstuvwxy") // hard
|
|
b.WriteString("z")
|
|
if err := b.Flush(); err != nil {
|
|
t.Error("WriteString", err)
|
|
}
|
|
s := "01234567890abcdefghijklmnopqrstuvwxyz"
|
|
if string(buf.Bytes()) != s {
|
|
t.Errorf("WriteString wants %q gets %q", s, string(buf.Bytes()))
|
|
}
|
|
}
|
|
|
|
func TestBufferFull(t *testing.T) {
|
|
const longString = "And now, hello, world! It is the time for all good men to come to the aid of their party"
|
|
buf := NewReaderSize(strings.NewReader(longString), minReadBufferSize)
|
|
line, err := buf.ReadSlice('!')
|
|
if string(line) != "And now, hello, " || err != ErrBufferFull {
|
|
t.Errorf("first ReadSlice(,) = %q, %v", line, err)
|
|
}
|
|
line, err = buf.ReadSlice('!')
|
|
if string(line) != "world!" || err != nil {
|
|
t.Errorf("second ReadSlice(,) = %q, %v", line, err)
|
|
}
|
|
}
|
|
|
|
func TestPeek(t *testing.T) {
|
|
p := make([]byte, 10)
|
|
// string is 16 (minReadBufferSize) long.
|
|
buf := NewReaderSize(strings.NewReader("abcdefghijklmnop"), minReadBufferSize)
|
|
if s, err := buf.Peek(1); string(s) != "a" || err != nil {
|
|
t.Fatalf("want %q got %q, err=%v", "a", string(s), err)
|
|
}
|
|
if s, err := buf.Peek(4); string(s) != "abcd" || err != nil {
|
|
t.Fatalf("want %q got %q, err=%v", "abcd", string(s), err)
|
|
}
|
|
if _, err := buf.Peek(-1); err != ErrNegativeCount {
|
|
t.Fatalf("want ErrNegativeCount got %v", err)
|
|
}
|
|
if s, err := buf.Peek(32); string(s) != "abcdefghijklmnop" || err != ErrBufferFull {
|
|
t.Fatalf("want %q, ErrBufFull got %q, err=%v", "abcdefghijklmnop", string(s), err)
|
|
}
|
|
if _, err := buf.Read(p[0:3]); string(p[0:3]) != "abc" || err != nil {
|
|
t.Fatalf("want %q got %q, err=%v", "abc", string(p[0:3]), err)
|
|
}
|
|
if s, err := buf.Peek(1); string(s) != "d" || err != nil {
|
|
t.Fatalf("want %q got %q, err=%v", "d", string(s), err)
|
|
}
|
|
if s, err := buf.Peek(2); string(s) != "de" || err != nil {
|
|
t.Fatalf("want %q got %q, err=%v", "de", string(s), err)
|
|
}
|
|
if _, err := buf.Read(p[0:3]); string(p[0:3]) != "def" || err != nil {
|
|
t.Fatalf("want %q got %q, err=%v", "def", string(p[0:3]), err)
|
|
}
|
|
if s, err := buf.Peek(4); string(s) != "ghij" || err != nil {
|
|
t.Fatalf("want %q got %q, err=%v", "ghij", string(s), err)
|
|
}
|
|
if _, err := buf.Read(p[0:]); string(p[0:]) != "ghijklmnop" || err != nil {
|
|
t.Fatalf("want %q got %q, err=%v", "ghijklmnop", string(p[0:minReadBufferSize]), err)
|
|
}
|
|
if s, err := buf.Peek(0); string(s) != "" || err != nil {
|
|
t.Fatalf("want %q got %q, err=%v", "", string(s), err)
|
|
}
|
|
if _, err := buf.Peek(1); err != io.EOF {
|
|
t.Fatalf("want EOF got %v", err)
|
|
}
|
|
|
|
// Test for issue 3022, not exposing a reader's error on a successful Peek.
|
|
buf = NewReaderSize(dataAndEOFReader("abcd"), 32)
|
|
if s, err := buf.Peek(2); string(s) != "ab" || err != nil {
|
|
t.Errorf(`Peek(2) on "abcd", EOF = %q, %v; want "ab", nil`, string(s), err)
|
|
}
|
|
if s, err := buf.Peek(4); string(s) != "abcd" || err != nil {
|
|
t.Errorf(`Peek(4) on "abcd", EOF = %q, %v; want "abcd", nil`, string(s), err)
|
|
}
|
|
if n, err := buf.Read(p[0:5]); string(p[0:n]) != "abcd" || err != nil {
|
|
t.Fatalf("Read after peek = %q, %v; want abcd, EOF", p[0:n], err)
|
|
}
|
|
if n, err := buf.Read(p[0:1]); string(p[0:n]) != "" || err != io.EOF {
|
|
t.Fatalf(`second Read after peek = %q, %v; want "", EOF`, p[0:n], err)
|
|
}
|
|
}
|
|
|
|
type dataAndEOFReader string
|
|
|
|
func (r dataAndEOFReader) Read(p []byte) (int, error) {
|
|
return copy(p, r), io.EOF
|
|
}
|
|
|
|
func TestPeekThenUnreadRune(t *testing.T) {
|
|
// This sequence used to cause a crash.
|
|
r := NewReader(strings.NewReader("x"))
|
|
r.ReadRune()
|
|
r.Peek(1)
|
|
r.UnreadRune()
|
|
r.ReadRune() // Used to panic here
|
|
}
|
|
|
|
var testOutput = []byte("0123456789abcdefghijklmnopqrstuvwxy")
|
|
var testInput = []byte("012\n345\n678\n9ab\ncde\nfgh\nijk\nlmn\nopq\nrst\nuvw\nxy")
|
|
var testInputrn = []byte("012\r\n345\r\n678\r\n9ab\r\ncde\r\nfgh\r\nijk\r\nlmn\r\nopq\r\nrst\r\nuvw\r\nxy\r\n\n\r\n")
|
|
|
|
// TestReader wraps a []byte and returns reads of a specific length.
|
|
type testReader struct {
|
|
data []byte
|
|
stride int
|
|
}
|
|
|
|
func (t *testReader) Read(buf []byte) (n int, err error) {
|
|
n = t.stride
|
|
if n > len(t.data) {
|
|
n = len(t.data)
|
|
}
|
|
if n > len(buf) {
|
|
n = len(buf)
|
|
}
|
|
copy(buf, t.data)
|
|
t.data = t.data[n:]
|
|
if len(t.data) == 0 {
|
|
err = io.EOF
|
|
}
|
|
return
|
|
}
|
|
|
|
func testReadLine(t *testing.T, input []byte) {
|
|
//for stride := 1; stride < len(input); stride++ {
|
|
for stride := 1; stride < 2; stride++ {
|
|
done := 0
|
|
reader := testReader{input, stride}
|
|
l := NewReaderSize(&reader, len(input)+1)
|
|
for {
|
|
line, isPrefix, err := l.ReadLine()
|
|
if len(line) > 0 && err != nil {
|
|
t.Errorf("ReadLine returned both data and error: %s", err)
|
|
}
|
|
if isPrefix {
|
|
t.Errorf("ReadLine returned prefix")
|
|
}
|
|
if err != nil {
|
|
if err != io.EOF {
|
|
t.Fatalf("Got unknown error: %s", err)
|
|
}
|
|
break
|
|
}
|
|
if want := testOutput[done : done+len(line)]; !bytes.Equal(want, line) {
|
|
t.Errorf("Bad line at stride %d: want: %x got: %x", stride, want, line)
|
|
}
|
|
done += len(line)
|
|
}
|
|
if done != len(testOutput) {
|
|
t.Errorf("ReadLine didn't return everything: got: %d, want: %d (stride: %d)", done, len(testOutput), stride)
|
|
}
|
|
}
|
|
}
|
|
|
|
func TestReadLine(t *testing.T) {
|
|
testReadLine(t, testInput)
|
|
testReadLine(t, testInputrn)
|
|
}
|
|
|
|
func TestLineTooLong(t *testing.T) {
|
|
data := make([]byte, 0)
|
|
for i := 0; i < minReadBufferSize*5/2; i++ {
|
|
data = append(data, '0'+byte(i%10))
|
|
}
|
|
buf := bytes.NewReader(data)
|
|
l := NewReaderSize(buf, minReadBufferSize)
|
|
line, isPrefix, err := l.ReadLine()
|
|
if !isPrefix || !bytes.Equal(line, data[:minReadBufferSize]) || err != nil {
|
|
t.Errorf("bad result for first line: got %q want %q %v", line, data[:minReadBufferSize], err)
|
|
}
|
|
data = data[len(line):]
|
|
line, isPrefix, err = l.ReadLine()
|
|
if !isPrefix || !bytes.Equal(line, data[:minReadBufferSize]) || err != nil {
|
|
t.Errorf("bad result for second line: got %q want %q %v", line, data[:minReadBufferSize], err)
|
|
}
|
|
data = data[len(line):]
|
|
line, isPrefix, err = l.ReadLine()
|
|
if isPrefix || !bytes.Equal(line, data[:minReadBufferSize/2]) || err != nil {
|
|
t.Errorf("bad result for third line: got %q want %q %v", line, data[:minReadBufferSize/2], err)
|
|
}
|
|
line, isPrefix, err = l.ReadLine()
|
|
if isPrefix || err == nil {
|
|
t.Errorf("expected no more lines: %x %s", line, err)
|
|
}
|
|
}
|
|
|
|
func TestReadAfterLines(t *testing.T) {
|
|
line1 := "this is line1"
|
|
restData := "this is line2\nthis is line 3\n"
|
|
inbuf := bytes.NewReader([]byte(line1 + "\n" + restData))
|
|
outbuf := new(bytes.Buffer)
|
|
maxLineLength := len(line1) + len(restData)/2
|
|
l := NewReaderSize(inbuf, maxLineLength)
|
|
line, isPrefix, err := l.ReadLine()
|
|
if isPrefix || err != nil || string(line) != line1 {
|
|
t.Errorf("bad result for first line: isPrefix=%v err=%v line=%q", isPrefix, err, string(line))
|
|
}
|
|
n, err := io.Copy(outbuf, l)
|
|
if int(n) != len(restData) || err != nil {
|
|
t.Errorf("bad result for Read: n=%d err=%v", n, err)
|
|
}
|
|
if outbuf.String() != restData {
|
|
t.Errorf("bad result for Read: got %q; expected %q", outbuf.String(), restData)
|
|
}
|
|
}
|
|
|
|
func TestReadEmptyBuffer(t *testing.T) {
|
|
l := NewReaderSize(new(bytes.Buffer), minReadBufferSize)
|
|
line, isPrefix, err := l.ReadLine()
|
|
if err != io.EOF {
|
|
t.Errorf("expected EOF from ReadLine, got '%s' %t %s", line, isPrefix, err)
|
|
}
|
|
}
|
|
|
|
func TestLinesAfterRead(t *testing.T) {
|
|
l := NewReaderSize(bytes.NewReader([]byte("foo")), minReadBufferSize)
|
|
_, err := ioutil.ReadAll(l)
|
|
if err != nil {
|
|
t.Error(err)
|
|
return
|
|
}
|
|
|
|
line, isPrefix, err := l.ReadLine()
|
|
if err != io.EOF {
|
|
t.Errorf("expected EOF from ReadLine, got '%s' %t %s", line, isPrefix, err)
|
|
}
|
|
}
|
|
|
|
func TestReadLineNonNilLineOrError(t *testing.T) {
|
|
r := NewReader(strings.NewReader("line 1\n"))
|
|
for i := 0; i < 2; i++ {
|
|
l, _, err := r.ReadLine()
|
|
if l != nil && err != nil {
|
|
t.Fatalf("on line %d/2; ReadLine=%#v, %v; want non-nil line or Error, but not both",
|
|
i+1, l, err)
|
|
}
|
|
}
|
|
}
|
|
|
|
type readLineResult struct {
|
|
line []byte
|
|
isPrefix bool
|
|
err error
|
|
}
|
|
|
|
var readLineNewlinesTests = []struct {
|
|
input string
|
|
expect []readLineResult
|
|
}{
|
|
{"012345678901234\r\n012345678901234\r\n", []readLineResult{
|
|
{[]byte("012345678901234"), true, nil},
|
|
{nil, false, nil},
|
|
{[]byte("012345678901234"), true, nil},
|
|
{nil, false, nil},
|
|
{nil, false, io.EOF},
|
|
}},
|
|
{"0123456789012345\r012345678901234\r", []readLineResult{
|
|
{[]byte("0123456789012345"), true, nil},
|
|
{[]byte("\r012345678901234"), true, nil},
|
|
{[]byte("\r"), false, nil},
|
|
{nil, false, io.EOF},
|
|
}},
|
|
}
|
|
|
|
func TestReadLineNewlines(t *testing.T) {
|
|
for _, e := range readLineNewlinesTests {
|
|
testReadLineNewlines(t, e.input, e.expect)
|
|
}
|
|
}
|
|
|
|
func testReadLineNewlines(t *testing.T, input string, expect []readLineResult) {
|
|
b := NewReaderSize(strings.NewReader(input), minReadBufferSize)
|
|
for i, e := range expect {
|
|
line, isPrefix, err := b.ReadLine()
|
|
if !bytes.Equal(line, e.line) {
|
|
t.Errorf("%q call %d, line == %q, want %q", input, i, line, e.line)
|
|
return
|
|
}
|
|
if isPrefix != e.isPrefix {
|
|
t.Errorf("%q call %d, isPrefix == %v, want %v", input, i, isPrefix, e.isPrefix)
|
|
return
|
|
}
|
|
if err != e.err {
|
|
t.Errorf("%q call %d, err == %v, want %v", input, i, err, e.err)
|
|
return
|
|
}
|
|
}
|
|
}
|
|
|
|
func createTestInput(n int) []byte {
|
|
input := make([]byte, n)
|
|
for i := range input {
|
|
// 101 and 251 are arbitrary prime numbers.
|
|
// The idea is to create an input sequence
|
|
// which doesn't repeat too frequently.
|
|
input[i] = byte(i % 251)
|
|
if i%101 == 0 {
|
|
input[i] ^= byte(i / 101)
|
|
}
|
|
}
|
|
return input
|
|
}
|
|
|
|
func TestReaderWriteTo(t *testing.T) {
|
|
input := createTestInput(8192)
|
|
r := NewReader(onlyReader{bytes.NewReader(input)})
|
|
w := new(bytes.Buffer)
|
|
if n, err := r.WriteTo(w); err != nil || n != int64(len(input)) {
|
|
t.Fatalf("r.WriteTo(w) = %d, %v, want %d, nil", n, err, len(input))
|
|
}
|
|
|
|
for i, val := range w.Bytes() {
|
|
if val != input[i] {
|
|
t.Errorf("after write: out[%d] = %#x, want %#x", i, val, input[i])
|
|
}
|
|
}
|
|
}
|
|
|
|
type errorWriterToTest struct {
|
|
rn, wn int
|
|
rerr, werr error
|
|
expected error
|
|
}
|
|
|
|
func (r errorWriterToTest) Read(p []byte) (int, error) {
|
|
return len(p) * r.rn, r.rerr
|
|
}
|
|
|
|
func (w errorWriterToTest) Write(p []byte) (int, error) {
|
|
return len(p) * w.wn, w.werr
|
|
}
|
|
|
|
var errorWriterToTests = []errorWriterToTest{
|
|
{1, 0, nil, io.ErrClosedPipe, io.ErrClosedPipe},
|
|
{0, 1, io.ErrClosedPipe, nil, io.ErrClosedPipe},
|
|
{0, 0, io.ErrUnexpectedEOF, io.ErrClosedPipe, io.ErrClosedPipe},
|
|
{0, 1, io.EOF, nil, nil},
|
|
}
|
|
|
|
func TestReaderWriteToErrors(t *testing.T) {
|
|
for i, rw := range errorWriterToTests {
|
|
r := NewReader(rw)
|
|
if _, err := r.WriteTo(rw); err != rw.expected {
|
|
t.Errorf("r.WriteTo(errorWriterToTests[%d]) = _, %v, want _,%v", i, err, rw.expected)
|
|
}
|
|
}
|
|
}
|
|
|
|
func TestWriterReadFrom(t *testing.T) {
|
|
ws := []func(io.Writer) io.Writer{
|
|
func(w io.Writer) io.Writer { return onlyWriter{w} },
|
|
func(w io.Writer) io.Writer { return w },
|
|
}
|
|
|
|
rs := []func(io.Reader) io.Reader{
|
|
iotest.DataErrReader,
|
|
func(r io.Reader) io.Reader { return r },
|
|
}
|
|
|
|
for ri, rfunc := range rs {
|
|
for wi, wfunc := range ws {
|
|
input := createTestInput(8192)
|
|
b := new(bytes.Buffer)
|
|
w := NewWriter(wfunc(b))
|
|
r := rfunc(bytes.NewReader(input))
|
|
if n, err := w.ReadFrom(r); err != nil || n != int64(len(input)) {
|
|
t.Errorf("ws[%d],rs[%d]: w.ReadFrom(r) = %d, %v, want %d, nil", wi, ri, n, err, len(input))
|
|
continue
|
|
}
|
|
if err := w.Flush(); err != nil {
|
|
t.Errorf("Flush returned %v", err)
|
|
continue
|
|
}
|
|
if got, want := b.String(), string(input); got != want {
|
|
t.Errorf("ws[%d], rs[%d]:\ngot %q\nwant %q\n", wi, ri, got, want)
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
type errorReaderFromTest struct {
|
|
rn, wn int
|
|
rerr, werr error
|
|
expected error
|
|
}
|
|
|
|
func (r errorReaderFromTest) Read(p []byte) (int, error) {
|
|
return len(p) * r.rn, r.rerr
|
|
}
|
|
|
|
func (w errorReaderFromTest) Write(p []byte) (int, error) {
|
|
return len(p) * w.wn, w.werr
|
|
}
|
|
|
|
var errorReaderFromTests = []errorReaderFromTest{
|
|
{0, 1, io.EOF, nil, nil},
|
|
{1, 1, io.EOF, nil, nil},
|
|
{0, 1, io.ErrClosedPipe, nil, io.ErrClosedPipe},
|
|
{0, 0, io.ErrClosedPipe, io.ErrShortWrite, io.ErrClosedPipe},
|
|
{1, 0, nil, io.ErrShortWrite, io.ErrShortWrite},
|
|
}
|
|
|
|
func TestWriterReadFromErrors(t *testing.T) {
|
|
for i, rw := range errorReaderFromTests {
|
|
w := NewWriter(rw)
|
|
if _, err := w.ReadFrom(rw); err != rw.expected {
|
|
t.Errorf("w.ReadFrom(errorReaderFromTests[%d]) = _, %v, want _,%v", i, err, rw.expected)
|
|
}
|
|
}
|
|
}
|
|
|
|
// TestWriterReadFromCounts tests that using io.Copy to copy into a
|
|
// bufio.Writer does not prematurely flush the buffer. For example, when
|
|
// buffering writes to a network socket, excessive network writes should be
|
|
// avoided.
|
|
func TestWriterReadFromCounts(t *testing.T) {
|
|
var w0 writeCountingDiscard
|
|
b0 := NewWriterSize(&w0, 1234)
|
|
b0.WriteString(strings.Repeat("x", 1000))
|
|
if w0 != 0 {
|
|
t.Fatalf("write 1000 'x's: got %d writes, want 0", w0)
|
|
}
|
|
b0.WriteString(strings.Repeat("x", 200))
|
|
if w0 != 0 {
|
|
t.Fatalf("write 1200 'x's: got %d writes, want 0", w0)
|
|
}
|
|
io.Copy(b0, onlyReader{strings.NewReader(strings.Repeat("x", 30))})
|
|
if w0 != 0 {
|
|
t.Fatalf("write 1230 'x's: got %d writes, want 0", w0)
|
|
}
|
|
io.Copy(b0, onlyReader{strings.NewReader(strings.Repeat("x", 9))})
|
|
if w0 != 1 {
|
|
t.Fatalf("write 1239 'x's: got %d writes, want 1", w0)
|
|
}
|
|
|
|
var w1 writeCountingDiscard
|
|
b1 := NewWriterSize(&w1, 1234)
|
|
b1.WriteString(strings.Repeat("x", 1200))
|
|
b1.Flush()
|
|
if w1 != 1 {
|
|
t.Fatalf("flush 1200 'x's: got %d writes, want 1", w1)
|
|
}
|
|
b1.WriteString(strings.Repeat("x", 89))
|
|
if w1 != 1 {
|
|
t.Fatalf("write 1200 + 89 'x's: got %d writes, want 1", w1)
|
|
}
|
|
io.Copy(b1, onlyReader{strings.NewReader(strings.Repeat("x", 700))})
|
|
if w1 != 1 {
|
|
t.Fatalf("write 1200 + 789 'x's: got %d writes, want 1", w1)
|
|
}
|
|
io.Copy(b1, onlyReader{strings.NewReader(strings.Repeat("x", 600))})
|
|
if w1 != 2 {
|
|
t.Fatalf("write 1200 + 1389 'x's: got %d writes, want 2", w1)
|
|
}
|
|
b1.Flush()
|
|
if w1 != 3 {
|
|
t.Fatalf("flush 1200 + 1389 'x's: got %d writes, want 3", w1)
|
|
}
|
|
}
|
|
|
|
// A writeCountingDiscard is like ioutil.Discard and counts the number of times
|
|
// Write is called on it.
|
|
type writeCountingDiscard int
|
|
|
|
func (w *writeCountingDiscard) Write(p []byte) (int, error) {
|
|
*w++
|
|
return len(p), nil
|
|
}
|
|
|
|
type negativeReader int
|
|
|
|
func (r *negativeReader) Read([]byte) (int, error) { return -1, nil }
|
|
|
|
func TestNegativeRead(t *testing.T) {
|
|
// should panic with a description pointing at the reader, not at itself.
|
|
// (should NOT panic with slice index error, for example.)
|
|
b := NewReader(new(negativeReader))
|
|
defer func() {
|
|
switch err := recover().(type) {
|
|
case nil:
|
|
t.Fatal("read did not panic")
|
|
case error:
|
|
if !strings.Contains(err.Error(), "reader returned negative count from Read") {
|
|
t.Fatalf("wrong panic: %v", err)
|
|
}
|
|
default:
|
|
t.Fatalf("unexpected panic value: %T(%v)", err, err)
|
|
}
|
|
}()
|
|
b.Read(make([]byte, 100))
|
|
}
|
|
|
|
var errFake = errors.New("fake error")
|
|
|
|
type errorThenGoodReader struct {
|
|
didErr bool
|
|
nread int
|
|
}
|
|
|
|
func (r *errorThenGoodReader) Read(p []byte) (int, error) {
|
|
r.nread++
|
|
if !r.didErr {
|
|
r.didErr = true
|
|
return 0, errFake
|
|
}
|
|
return len(p), nil
|
|
}
|
|
|
|
func TestReaderClearError(t *testing.T) {
|
|
r := &errorThenGoodReader{}
|
|
b := NewReader(r)
|
|
buf := make([]byte, 1)
|
|
if _, err := b.Read(nil); err != nil {
|
|
t.Fatalf("1st nil Read = %v; want nil", err)
|
|
}
|
|
if _, err := b.Read(buf); err != errFake {
|
|
t.Fatalf("1st Read = %v; want errFake", err)
|
|
}
|
|
if _, err := b.Read(nil); err != nil {
|
|
t.Fatalf("2nd nil Read = %v; want nil", err)
|
|
}
|
|
if _, err := b.Read(buf); err != nil {
|
|
t.Fatalf("3rd Read with buffer = %v; want nil", err)
|
|
}
|
|
if r.nread != 2 {
|
|
t.Errorf("num reads = %d; want 2", r.nread)
|
|
}
|
|
}
|
|
|
|
// Test for golang.org/issue/5947
|
|
func TestWriterReadFromWhileFull(t *testing.T) {
|
|
buf := new(bytes.Buffer)
|
|
w := NewWriterSize(buf, 10)
|
|
|
|
// Fill buffer exactly.
|
|
n, err := w.Write([]byte("0123456789"))
|
|
if n != 10 || err != nil {
|
|
t.Fatalf("Write returned (%v, %v), want (10, nil)", n, err)
|
|
}
|
|
|
|
// Use ReadFrom to read in some data.
|
|
n2, err := w.ReadFrom(strings.NewReader("abcdef"))
|
|
if n2 != 6 || err != nil {
|
|
t.Fatalf("ReadFrom returned (%v, %v), want (6, nil)", n2, err)
|
|
}
|
|
}
|
|
|
|
type emptyThenNonEmptyReader struct {
|
|
r io.Reader
|
|
n int
|
|
}
|
|
|
|
func (r *emptyThenNonEmptyReader) Read(p []byte) (int, error) {
|
|
if r.n <= 0 {
|
|
return r.r.Read(p)
|
|
}
|
|
r.n--
|
|
return 0, nil
|
|
}
|
|
|
|
// Test for golang.org/issue/7611
|
|
func TestWriterReadFromUntilEOF(t *testing.T) {
|
|
buf := new(bytes.Buffer)
|
|
w := NewWriterSize(buf, 5)
|
|
|
|
// Partially fill buffer
|
|
n, err := w.Write([]byte("0123"))
|
|
if n != 4 || err != nil {
|
|
t.Fatalf("Write returned (%v, %v), want (4, nil)", n, err)
|
|
}
|
|
|
|
// Use ReadFrom to read in some data.
|
|
r := &emptyThenNonEmptyReader{r: strings.NewReader("abcd"), n: 3}
|
|
n2, err := w.ReadFrom(r)
|
|
if n2 != 4 || err != nil {
|
|
t.Fatalf("ReadFrom returned (%v, %v), want (4, nil)", n2, err)
|
|
}
|
|
w.Flush()
|
|
if got, want := string(buf.Bytes()), "0123abcd"; got != want {
|
|
t.Fatalf("buf.Bytes() returned %q, want %q", got, want)
|
|
}
|
|
}
|
|
|
|
func TestWriterReadFromErrNoProgress(t *testing.T) {
|
|
buf := new(bytes.Buffer)
|
|
w := NewWriterSize(buf, 5)
|
|
|
|
// Partially fill buffer
|
|
n, err := w.Write([]byte("0123"))
|
|
if n != 4 || err != nil {
|
|
t.Fatalf("Write returned (%v, %v), want (4, nil)", n, err)
|
|
}
|
|
|
|
// Use ReadFrom to read in some data.
|
|
r := &emptyThenNonEmptyReader{r: strings.NewReader("abcd"), n: 100}
|
|
n2, err := w.ReadFrom(r)
|
|
if n2 != 0 || err != io.ErrNoProgress {
|
|
t.Fatalf("buf.Bytes() returned (%v, %v), want (0, io.ErrNoProgress)", n2, err)
|
|
}
|
|
}
|
|
|
|
func TestReaderReset(t *testing.T) {
|
|
r := NewReader(strings.NewReader("foo foo"))
|
|
buf := make([]byte, 3)
|
|
r.Read(buf)
|
|
if string(buf) != "foo" {
|
|
t.Errorf("buf = %q; want foo", buf)
|
|
}
|
|
r.Reset(strings.NewReader("bar bar"))
|
|
all, err := ioutil.ReadAll(r)
|
|
if err != nil {
|
|
t.Fatal(err)
|
|
}
|
|
if string(all) != "bar bar" {
|
|
t.Errorf("ReadAll = %q; want bar bar", all)
|
|
}
|
|
}
|
|
|
|
func TestWriterReset(t *testing.T) {
|
|
var buf1, buf2 bytes.Buffer
|
|
w := NewWriter(&buf1)
|
|
w.WriteString("foo")
|
|
w.Reset(&buf2) // and not flushed
|
|
w.WriteString("bar")
|
|
w.Flush()
|
|
if buf1.String() != "" {
|
|
t.Errorf("buf1 = %q; want empty", buf1.String())
|
|
}
|
|
if buf2.String() != "bar" {
|
|
t.Errorf("buf2 = %q; want bar", buf2.String())
|
|
}
|
|
}
|
|
|
|
func TestReaderDiscard(t *testing.T) {
|
|
tests := []struct {
|
|
name string
|
|
r io.Reader
|
|
bufSize int // 0 means 16
|
|
peekSize int
|
|
|
|
n int // input to Discard
|
|
|
|
want int // from Discard
|
|
wantErr error // from Discard
|
|
|
|
wantBuffered int
|
|
}{
|
|
{
|
|
name: "normal case",
|
|
r: strings.NewReader("abcdefghijklmnopqrstuvwxyz"),
|
|
peekSize: 16,
|
|
n: 6,
|
|
want: 6,
|
|
wantBuffered: 10,
|
|
},
|
|
{
|
|
name: "discard causing read",
|
|
r: strings.NewReader("abcdefghijklmnopqrstuvwxyz"),
|
|
n: 6,
|
|
want: 6,
|
|
wantBuffered: 10,
|
|
},
|
|
{
|
|
name: "discard all without peek",
|
|
r: strings.NewReader("abcdefghijklmnopqrstuvwxyz"),
|
|
n: 26,
|
|
want: 26,
|
|
wantBuffered: 0,
|
|
},
|
|
{
|
|
name: "discard more than end",
|
|
r: strings.NewReader("abcdefghijklmnopqrstuvwxyz"),
|
|
n: 27,
|
|
want: 26,
|
|
wantErr: io.EOF,
|
|
wantBuffered: 0,
|
|
},
|
|
// Any error from filling shouldn't show up until we
|
|
// get past the valid bytes. Here we return we return 5 valid bytes at the same time
|
|
// as an error, but test that we don't see the error from Discard.
|
|
{
|
|
name: "fill error, discard less",
|
|
r: newScriptedReader(func(p []byte) (n int, err error) {
|
|
if len(p) < 5 {
|
|
panic("unexpected small read")
|
|
}
|
|
return 5, errors.New("5-then-error")
|
|
}),
|
|
n: 4,
|
|
want: 4,
|
|
wantErr: nil,
|
|
wantBuffered: 1,
|
|
},
|
|
{
|
|
name: "fill error, discard equal",
|
|
r: newScriptedReader(func(p []byte) (n int, err error) {
|
|
if len(p) < 5 {
|
|
panic("unexpected small read")
|
|
}
|
|
return 5, errors.New("5-then-error")
|
|
}),
|
|
n: 5,
|
|
want: 5,
|
|
wantErr: nil,
|
|
wantBuffered: 0,
|
|
},
|
|
{
|
|
name: "fill error, discard more",
|
|
r: newScriptedReader(func(p []byte) (n int, err error) {
|
|
if len(p) < 5 {
|
|
panic("unexpected small read")
|
|
}
|
|
return 5, errors.New("5-then-error")
|
|
}),
|
|
n: 6,
|
|
want: 5,
|
|
wantErr: errors.New("5-then-error"),
|
|
wantBuffered: 0,
|
|
},
|
|
// Discard of 0 shouldn't cause a read:
|
|
{
|
|
name: "discard zero",
|
|
r: newScriptedReader(), // will panic on Read
|
|
n: 0,
|
|
want: 0,
|
|
wantErr: nil,
|
|
wantBuffered: 0,
|
|
},
|
|
{
|
|
name: "discard negative",
|
|
r: newScriptedReader(), // will panic on Read
|
|
n: -1,
|
|
want: 0,
|
|
wantErr: ErrNegativeCount,
|
|
wantBuffered: 0,
|
|
},
|
|
}
|
|
for _, tt := range tests {
|
|
br := NewReaderSize(tt.r, tt.bufSize)
|
|
if tt.peekSize > 0 {
|
|
peekBuf, err := br.Peek(tt.peekSize)
|
|
if err != nil {
|
|
t.Errorf("%s: Peek(%d): %v", tt.name, tt.peekSize, err)
|
|
continue
|
|
}
|
|
if len(peekBuf) != tt.peekSize {
|
|
t.Errorf("%s: len(Peek(%d)) = %v; want %v", tt.name, tt.peekSize, len(peekBuf), tt.peekSize)
|
|
continue
|
|
}
|
|
}
|
|
discarded, err := br.Discard(tt.n)
|
|
if ge, we := fmt.Sprint(err), fmt.Sprint(tt.wantErr); discarded != tt.want || ge != we {
|
|
t.Errorf("%s: Discard(%d) = (%v, %v); want (%v, %v)", tt.name, tt.n, discarded, ge, tt.want, we)
|
|
continue
|
|
}
|
|
if bn := br.Buffered(); bn != tt.wantBuffered {
|
|
t.Errorf("%s: after Discard, Buffered = %d; want %d", tt.name, bn, tt.wantBuffered)
|
|
}
|
|
}
|
|
|
|
}
|
|
|
|
// An onlyReader only implements io.Reader, no matter what other methods the underlying implementation may have.
|
|
type onlyReader struct {
|
|
io.Reader
|
|
}
|
|
|
|
// An onlyWriter only implements io.Writer, no matter what other methods the underlying implementation may have.
|
|
type onlyWriter struct {
|
|
io.Writer
|
|
}
|
|
|
|
// A scriptedReader is an io.Reader that executes its steps sequentially.
|
|
type scriptedReader []func(p []byte) (n int, err error)
|
|
|
|
func (sr *scriptedReader) Read(p []byte) (n int, err error) {
|
|
if len(*sr) == 0 {
|
|
panic("too many Read calls on scripted Reader. No steps remain.")
|
|
}
|
|
step := (*sr)[0]
|
|
*sr = (*sr)[1:]
|
|
return step(p)
|
|
}
|
|
|
|
func newScriptedReader(steps ...func(p []byte) (n int, err error)) io.Reader {
|
|
sr := scriptedReader(steps)
|
|
return &sr
|
|
}
|
|
|
|
func BenchmarkReaderCopyOptimal(b *testing.B) {
|
|
// Optimal case is where the underlying reader implements io.WriterTo
|
|
srcBuf := bytes.NewBuffer(make([]byte, 8192))
|
|
src := NewReader(srcBuf)
|
|
dstBuf := new(bytes.Buffer)
|
|
dst := onlyWriter{dstBuf}
|
|
for i := 0; i < b.N; i++ {
|
|
srcBuf.Reset()
|
|
src.Reset(srcBuf)
|
|
dstBuf.Reset()
|
|
io.Copy(dst, src)
|
|
}
|
|
}
|
|
|
|
func BenchmarkReaderCopyUnoptimal(b *testing.B) {
|
|
// Unoptimal case is where the underlying reader doesn't implement io.WriterTo
|
|
srcBuf := bytes.NewBuffer(make([]byte, 8192))
|
|
src := NewReader(onlyReader{srcBuf})
|
|
dstBuf := new(bytes.Buffer)
|
|
dst := onlyWriter{dstBuf}
|
|
for i := 0; i < b.N; i++ {
|
|
srcBuf.Reset()
|
|
src.Reset(onlyReader{srcBuf})
|
|
dstBuf.Reset()
|
|
io.Copy(dst, src)
|
|
}
|
|
}
|
|
|
|
func BenchmarkReaderCopyNoWriteTo(b *testing.B) {
|
|
srcBuf := bytes.NewBuffer(make([]byte, 8192))
|
|
srcReader := NewReader(srcBuf)
|
|
src := onlyReader{srcReader}
|
|
dstBuf := new(bytes.Buffer)
|
|
dst := onlyWriter{dstBuf}
|
|
for i := 0; i < b.N; i++ {
|
|
srcBuf.Reset()
|
|
srcReader.Reset(srcBuf)
|
|
dstBuf.Reset()
|
|
io.Copy(dst, src)
|
|
}
|
|
}
|
|
|
|
func BenchmarkReaderWriteToOptimal(b *testing.B) {
|
|
const bufSize = 16 << 10
|
|
buf := make([]byte, bufSize)
|
|
r := bytes.NewReader(buf)
|
|
srcReader := NewReaderSize(onlyReader{r}, 1<<10)
|
|
if _, ok := ioutil.Discard.(io.ReaderFrom); !ok {
|
|
b.Fatal("ioutil.Discard doesn't support ReaderFrom")
|
|
}
|
|
for i := 0; i < b.N; i++ {
|
|
r.Seek(0, io.SeekStart)
|
|
srcReader.Reset(onlyReader{r})
|
|
n, err := srcReader.WriteTo(ioutil.Discard)
|
|
if err != nil {
|
|
b.Fatal(err)
|
|
}
|
|
if n != bufSize {
|
|
b.Fatalf("n = %d; want %d", n, bufSize)
|
|
}
|
|
}
|
|
}
|
|
|
|
func BenchmarkWriterCopyOptimal(b *testing.B) {
|
|
// Optimal case is where the underlying writer implements io.ReaderFrom
|
|
srcBuf := bytes.NewBuffer(make([]byte, 8192))
|
|
src := onlyReader{srcBuf}
|
|
dstBuf := new(bytes.Buffer)
|
|
dst := NewWriter(dstBuf)
|
|
for i := 0; i < b.N; i++ {
|
|
srcBuf.Reset()
|
|
dstBuf.Reset()
|
|
dst.Reset(dstBuf)
|
|
io.Copy(dst, src)
|
|
}
|
|
}
|
|
|
|
func BenchmarkWriterCopyUnoptimal(b *testing.B) {
|
|
srcBuf := bytes.NewBuffer(make([]byte, 8192))
|
|
src := onlyReader{srcBuf}
|
|
dstBuf := new(bytes.Buffer)
|
|
dst := NewWriter(onlyWriter{dstBuf})
|
|
for i := 0; i < b.N; i++ {
|
|
srcBuf.Reset()
|
|
dstBuf.Reset()
|
|
dst.Reset(onlyWriter{dstBuf})
|
|
io.Copy(dst, src)
|
|
}
|
|
}
|
|
|
|
func BenchmarkWriterCopyNoReadFrom(b *testing.B) {
|
|
srcBuf := bytes.NewBuffer(make([]byte, 8192))
|
|
src := onlyReader{srcBuf}
|
|
dstBuf := new(bytes.Buffer)
|
|
dstWriter := NewWriter(dstBuf)
|
|
dst := onlyWriter{dstWriter}
|
|
for i := 0; i < b.N; i++ {
|
|
srcBuf.Reset()
|
|
dstBuf.Reset()
|
|
dstWriter.Reset(dstBuf)
|
|
io.Copy(dst, src)
|
|
}
|
|
}
|
|
|
|
func BenchmarkReaderEmpty(b *testing.B) {
|
|
b.ReportAllocs()
|
|
str := strings.Repeat("x", 16<<10)
|
|
for i := 0; i < b.N; i++ {
|
|
br := NewReader(strings.NewReader(str))
|
|
n, err := io.Copy(ioutil.Discard, br)
|
|
if err != nil {
|
|
b.Fatal(err)
|
|
}
|
|
if n != int64(len(str)) {
|
|
b.Fatal("wrong length")
|
|
}
|
|
}
|
|
}
|
|
|
|
func BenchmarkWriterEmpty(b *testing.B) {
|
|
b.ReportAllocs()
|
|
str := strings.Repeat("x", 1<<10)
|
|
bs := []byte(str)
|
|
for i := 0; i < b.N; i++ {
|
|
bw := NewWriter(ioutil.Discard)
|
|
bw.Flush()
|
|
bw.WriteByte('a')
|
|
bw.Flush()
|
|
bw.WriteRune('B')
|
|
bw.Flush()
|
|
bw.Write(bs)
|
|
bw.Flush()
|
|
bw.WriteString(str)
|
|
bw.Flush()
|
|
}
|
|
}
|
|
|
|
func BenchmarkWriterFlush(b *testing.B) {
|
|
b.ReportAllocs()
|
|
bw := NewWriter(ioutil.Discard)
|
|
str := strings.Repeat("x", 50)
|
|
for i := 0; i < b.N; i++ {
|
|
bw.WriteString(str)
|
|
bw.Flush()
|
|
}
|
|
}
|