pax_global_header00006660000000000000000000000064130551210370014507gustar00rootroot0000000000000052 comment=c37440a7cf42ac63b919c752ca73a85067e05992 go-buffruneio-0.2.0/000077500000000000000000000000001305512103700142555ustar00rootroot00000000000000go-buffruneio-0.2.0/.gitignore000066400000000000000000000000061305512103700162410ustar00rootroot00000000000000*.testgo-buffruneio-0.2.0/.travis.yml000066400000000000000000000001131305512103700163610ustar00rootroot00000000000000language: go sudo: false go: - 1.3.3 - 1.4.3 - 1.5.3 - tip go-buffruneio-0.2.0/README.md000066400000000000000000000042551305512103700155420ustar00rootroot00000000000000# buffruneio [![Tests Status](https://travis-ci.org/pelletier/go-buffruneio.svg?branch=master)](https://travis-ci.org/pelletier/go-buffruneio) [![GoDoc](https://godoc.org/github.com/pelletier/go-buffruneio?status.svg)](https://godoc.org/github.com/pelletier/go-buffruneio) Buffruneio is a wrapper around bufio to provide buffered runes access with unlimited unreads. ```go import "github.com/pelletier/go-buffruneio" ``` ## Examples ```go import ( "fmt" "github.com/pelletier/go-buffruneio" "strings" ) reader := buffruneio.NewReader(strings.NewReader("abcd")) fmt.Println(reader.ReadRune()) // 'a' fmt.Println(reader.ReadRune()) // 'b' fmt.Println(reader.ReadRune()) // 'c' reader.UnreadRune() reader.UnreadRune() fmt.Println(reader.ReadRune()) // 'b' fmt.Println(reader.ReadRune()) // 'c' ``` ## Documentation The documentation and additional examples are available at [godoc.org](http://godoc.org/github.com/pelletier/go-buffruneio). ## Contribute Feel free to report bugs and patches using GitHub's pull requests system on [pelletier/go-toml](https://github.com/pelletier/go-buffruneio). Any feedback is much appreciated! ## LICENSE Copyright (c) 2016 Thomas Pelletier Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. go-buffruneio-0.2.0/buffruneio.go000066400000000000000000000050271305512103700167540ustar00rootroot00000000000000// Package buffruneio is a wrapper around bufio to provide buffered runes access with unlimited unreads. package buffruneio import ( "bufio" "container/list" "errors" "io" ) // Rune to indicate end of file. const ( EOF = -(iota + 1) ) // ErrNoRuneToUnread is returned by UnreadRune() when the read index is already at the beginning of the buffer. var ErrNoRuneToUnread = errors.New("no rune to unwind") // Reader implements runes buffering for an io.Reader object. type Reader struct { buffer *list.List current *list.Element input *bufio.Reader } // NewReader returns a new Reader. func NewReader(rd io.Reader) *Reader { return &Reader{ buffer: list.New(), input: bufio.NewReader(rd), } } type runeWithSize struct { r rune size int } func (rd *Reader) feedBuffer() error { r, size, err := rd.input.ReadRune() if err != nil { if err != io.EOF { return err } r = EOF } newRuneWithSize := runeWithSize{r, size} rd.buffer.PushBack(newRuneWithSize) if rd.current == nil { rd.current = rd.buffer.Back() } return nil } // ReadRune reads the next rune from buffer, or from the underlying reader if needed. func (rd *Reader) ReadRune() (rune, int, error) { if rd.current == rd.buffer.Back() || rd.current == nil { err := rd.feedBuffer() if err != nil { return EOF, 0, err } } runeWithSize := rd.current.Value.(runeWithSize) rd.current = rd.current.Next() return runeWithSize.r, runeWithSize.size, nil } // UnreadRune pushes back the previously read rune in the buffer, extending it if needed. func (rd *Reader) UnreadRune() error { if rd.current == rd.buffer.Front() { return ErrNoRuneToUnread } if rd.current == nil { rd.current = rd.buffer.Back() } else { rd.current = rd.current.Prev() } return nil } // Forget removes runes stored before the current stream position index. func (rd *Reader) Forget() { if rd.current == nil { rd.current = rd.buffer.Back() } for ; rd.current != rd.buffer.Front(); rd.buffer.Remove(rd.current.Prev()) { } } // PeekRune returns at most the next n runes, reading from the uderlying source if // needed. Does not move the current index. It includes EOF if reached. func (rd *Reader) PeekRunes(n int) []rune { res := make([]rune, 0, n) cursor := rd.current for i := 0; i < n; i++ { if cursor == nil { err := rd.feedBuffer() if err != nil { return res } cursor = rd.buffer.Back() } if cursor != nil { r := cursor.Value.(runeWithSize).r res = append(res, r) if r == EOF { return res } cursor = cursor.Next() } } return res } go-buffruneio-0.2.0/buffruneio_test.go000066400000000000000000000056071305512103700200170ustar00rootroot00000000000000package buffruneio import ( "runtime/debug" "strings" "testing" ) func assertNoError(t *testing.T, err error) { if err != nil { t.Log("unexpected error", err) debug.PrintStack() t.FailNow() } } func assumeRunesArray(t *testing.T, expected []rune, got []rune) { if len(expected) != len(got) { t.Fatal("expected", len(expected), "runes, but got", len(got)) } for i := 0; i < len(got); i++ { if expected[i] != got[i] { t.Fatal("expected rune", expected[i], "at index", i, "but got", got[i]) } } } func assumeRune(t *testing.T, rd *Reader, r rune) { gotRune, size, err := rd.ReadRune() assertNoError(t, err) if gotRune != r { t.Fatal("got", string(gotRune), "(", []byte(string(gotRune)), ")", "expected", string(r), "(", []byte(string(r)), ")") t.Fatal("got size", size, "expected", len([]byte(string(r)))) } } func TestReadString(t *testing.T) { s := "hello" rd := NewReader(strings.NewReader(s)) assumeRune(t, rd, 'h') assumeRune(t, rd, 'e') assumeRune(t, rd, 'l') assumeRune(t, rd, 'l') assumeRune(t, rd, 'o') assumeRune(t, rd, EOF) } func TestMultipleEOF(t *testing.T) { s := "" rd := NewReader(strings.NewReader(s)) assumeRune(t, rd, EOF) assumeRune(t, rd, EOF) } func TestUnread(t *testing.T) { s := "ab" rd := NewReader(strings.NewReader(s)) assumeRune(t, rd, 'a') assumeRune(t, rd, 'b') assertNoError(t, rd.UnreadRune()) assumeRune(t, rd, 'b') assumeRune(t, rd, EOF) } func TestUnreadEOF(t *testing.T) { s := "" rd := NewReader(strings.NewReader(s)) _ = rd.UnreadRune() assumeRune(t, rd, EOF) assumeRune(t, rd, EOF) assertNoError(t, rd.UnreadRune()) assumeRune(t, rd, EOF) } func TestForget(t *testing.T) { s := "hello" rd := NewReader(strings.NewReader(s)) assumeRune(t, rd, 'h') assumeRune(t, rd, 'e') assumeRune(t, rd, 'l') assumeRune(t, rd, 'l') rd.Forget() if rd.UnreadRune() != ErrNoRuneToUnread { t.Fatal("no rune should be available") } } func TestForgetEmpty(t *testing.T) { s := "" rd := NewReader(strings.NewReader(s)) rd.Forget() assumeRune(t, rd, EOF) rd.Forget() } func TestPeekEmpty(t *testing.T) { s := "" rd := NewReader(strings.NewReader(s)) runes := rd.PeekRunes(1) if len(runes) != 1 { t.Fatal("incorrect number of runes", len(runes)) } if runes[0] != EOF { t.Fatal("incorrect rune", runes[0]) } } func TestPeek(t *testing.T) { s := "a" rd := NewReader(strings.NewReader(s)) runes := rd.PeekRunes(1) assumeRunesArray(t, []rune{'a'}, runes) runes = rd.PeekRunes(1) assumeRunesArray(t, []rune{'a'}, runes) assumeRune(t, rd, 'a') runes = rd.PeekRunes(1) assumeRunesArray(t, []rune{EOF}, runes) assumeRune(t, rd, EOF) } func TestPeekLarge(t *testing.T) { s := "abcdefg" rd := NewReader(strings.NewReader(s)) runes := rd.PeekRunes(100) if len(runes) != len(s)+1 { t.Fatal("incorrect number of runes", len(runes)) } assumeRunesArray(t, []rune{'a', 'b', 'c', 'd', 'e', 'f', 'g', EOF}, runes) }