bytes: Add Buffer.ReadBytes, Buffer.ReadString
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/4000046
diff --git a/src/pkg/bufio/bufio.go b/src/pkg/bufio/bufio.go
index c13456a..67b7cdb 100644
--- a/src/pkg/bufio/bufio.go
+++ b/src/pkg/bufio/bufio.go
@@ -286,7 +286,8 @@
// returning a slice containing the data up to and including the delimiter.
// If ReadBytes encounters an error before finding a delimiter,
// it returns the data read before the error and the error itself (often os.EOF).
-// ReadBytes returns err != nil if and only if line does not end in delim.
+// ReadBytes returns err != nil if and only if the returned data does not end in
+// delim.
func (b *Reader) ReadBytes(delim byte) (line []byte, err os.Error) {
// Use ReadSlice to look for array,
// accumulating full buffers.
@@ -332,7 +333,8 @@
// returning a string containing the data up to and including the delimiter.
// If ReadString encounters an error before finding a delimiter,
// it returns the data read before the error and the error itself (often os.EOF).
-// ReadString returns err != nil if and only if line does not end in delim.
+// ReadString returns err != nil if and only if the returned data does not end in
+// delim.
func (b *Reader) ReadString(delim byte) (line string, err os.Error) {
bytes, e := b.ReadBytes(delim)
return string(bytes), e
diff --git a/src/pkg/bytes/buffer.go b/src/pkg/bytes/buffer.go
index 62cf828..4aa7437 100644
--- a/src/pkg/bytes/buffer.go
+++ b/src/pkg/bytes/buffer.go
@@ -301,6 +301,35 @@
return nil
}
+// ReadBytes reads until the first occurrence of delim in the input,
+// returning a slice containing the data up to and including the delimiter.
+// If ReadBytes encounters an error before finding a delimiter,
+// it returns the data read before the error and the error itself (often os.EOF).
+// ReadBytes returns err != nil if and only if the returned data does not end in
+// delim.
+func (b *Buffer) ReadBytes(delim byte) (line []byte, err os.Error) {
+ i := IndexByte(b.buf[b.off:], delim)
+ size := i + 1 - b.off
+ if i < 0 {
+ size = len(b.buf) - b.off
+ err = os.EOF
+ }
+ line = make([]byte, size)
+ copy(line, b.buf[b.off:])
+ return
+}
+
+// ReadString reads until the first occurrence of delim in the input,
+// returning a string containing the data up to and including the delimiter.
+// If ReadString encounters an error before finding a delimiter,
+// it returns the data read before the error and the error itself (often os.EOF).
+// ReadString returns err != nil if and only if the returned data does not end
+// in delim.
+func (b *Buffer) ReadString(delim byte) (line string, err os.Error) {
+ bytes, err := b.ReadBytes(delim)
+ return string(bytes), err
+}
+
// NewBuffer creates and initializes a new Buffer using buf as its initial
// contents. It is intended to prepare a Buffer to read existing data. It
// can also be used to size the internal buffer for writing. To do that,
diff --git a/src/pkg/bytes/buffer_test.go b/src/pkg/bytes/buffer_test.go
index 509793d..2af9ffd 100644
--- a/src/pkg/bytes/buffer_test.go
+++ b/src/pkg/bytes/buffer_test.go
@@ -6,6 +6,7 @@
import (
. "bytes"
+ "os"
"rand"
"testing"
"utf8"
@@ -238,7 +239,7 @@
func TestNil(t *testing.T) {
var b *Buffer
if b.String() != "<nil>" {
- t.Errorf("expcted <nil>; got %q", b.String())
+ t.Errorf("expected <nil>; got %q", b.String())
}
}
@@ -347,3 +348,27 @@
}
}
}
+
+var readBytesTests = []struct {
+ buffer []byte
+ delim byte
+ expected []byte
+ err os.Error
+}{
+ {err: os.EOF},
+ {[]byte{}, 0, []byte{}, os.EOF},
+ {[]byte("a\x00"), 0, []byte("a\x00"), nil},
+ {[]byte("hello\x01world"), 1, []byte("hello\x01"), nil},
+ {[]byte("foo\nbar"), 0, []byte("foo\nbar"), os.EOF},
+ {[]byte("alpha beta gamma"), ' ', []byte("alpha "), nil},
+}
+
+func TestReadBytes(t *testing.T) {
+ for _, test := range readBytesTests {
+ buf := NewBuffer(test.buffer)
+ bytes, err := buf.ReadBytes(test.delim)
+ if !Equal(bytes, test.expected) || err != test.err {
+ t.Errorf("expected %q, %v got %q, %v", test.expected, test.err, bytes, err)
+ }
+ }
+}
