Add self-contained gometalinter build tooling.

tools/vendor/github.com/Bowery/prompt/buffer.go

@@ -0,0 +1,152 @@
+// Copyright 2013-2015 Bowery, Inc.
+
+package prompt
+
+import (
+	"os"
+	"unicode/utf8"
+)
+
+// Buffer contains state for line editing and writing.
+type Buffer struct {
+	Out    *os.File
+	Prompt string
+	Echo   bool
+	Cols   int
+	pos    int
+	size   int
+	data   []rune
+}
+
+// NewBuffer creates a buffer writing to out if echo is true.
+func NewBuffer(prompt string, out *os.File, echo bool) *Buffer {
+	return &Buffer{
+		Out:    out,
+		Prompt: prompt,
+		Echo:   echo,
+	}
+}
+
+// String returns the data as a string.
+func (buf *Buffer) String() string {
+	return string(buf.data[:buf.size])
+}
+
+// Insert inserts characters at the cursors position.
+func (buf *Buffer) Insert(rs ...rune) error {
+	rsLen := len(rs)
+	total := buf.size + rsLen
+
+	if total > len(buf.data) {
+		buf.data = append(buf.data, make([]rune, rsLen)...)
+	}
+
+	// Shift characters to make room in the correct pos.
+	if buf.size != buf.pos {
+		copy(buf.data[buf.pos+rsLen:buf.size+rsLen], buf.data[buf.pos:buf.size])
+	}
+
+	for _, r := range rs {
+		buf.data[buf.pos] = r
+		buf.pos++
+		buf.size++
+	}
+
+	return buf.Refresh()
+}
+
+// Set sets the content in the buffer.
+func (buf *Buffer) Set(rs ...rune) error {
+	rsLen := len(rs)
+	buf.data = rs
+	buf.pos = rsLen
+	buf.size = rsLen
+
+	return buf.Refresh()
+}
+
+// Start moves the cursor to the start.
+func (buf *Buffer) Start() error {
+	if buf.pos <= 0 {
+		return nil
+	}
+
+	buf.pos = 0
+	return buf.Refresh()
+}
+
+// End moves the cursor to the end.
+func (buf *Buffer) End() error {
+	if buf.pos >= buf.size {
+		return nil
+	}
+
+	buf.pos = buf.size
+	return buf.Refresh()
+}
+
+// Left moves the cursor one character left.
+func (buf *Buffer) Left() error {
+	if buf.pos <= 0 {
+		return nil
+	}
+
+	buf.pos--
+	return buf.Refresh()
+}
+
+// Right moves the cursor one character right.
+func (buf *Buffer) Right() error {
+	if buf.pos >= buf.size {
+		return nil
+	}
+
+	buf.pos++
+	return buf.Refresh()
+}
+
+// Del removes the character at the cursor position.
+func (buf *Buffer) Del() error {
+	if buf.pos >= buf.size {
+		return nil
+	}
+
+	// Shift characters after position back one.
+	copy(buf.data[buf.pos:], buf.data[buf.pos+1:buf.size])
+	buf.size--
+
+	return buf.Refresh()
+}
+
+// DelLeft removes the character to the left.
+func (buf *Buffer) DelLeft() error {
+	if buf.pos <= 0 {
+		return nil
+	}
+
+	// Shift characters from position back one.
+	copy(buf.data[buf.pos-1:], buf.data[buf.pos:buf.size])
+	buf.pos--
+	buf.size--
+
+	return buf.Refresh()
+}
+
+// EndLine ends the line with CRLF.
+func (buf *Buffer) EndLine() error {
+	_, err := buf.Out.Write(crlf)
+	return err
+}
+
+// toBytes converts a slice of runes to its equivalent in bytes.
+func toBytes(runes []rune) []byte {
+	var bytes []byte
+	char := make([]byte, utf8.UTFMax)
+
+	for _, r := range runes {
+		n := utf8.EncodeRune(char, r)
+		bytes = append(bytes, char[:n]...)
+	}
+
+	return bytes
+}