non-colorable

noncolorable.go

@@ -0,0 +1,57 @@
+package colorable
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+)
+
+type NonColorable struct {
+	out     io.Writer
+	lastbuf bytes.Buffer
+}
+
+func NewNonColorable(w io.Writer) io.Writer {
+	return &NonColorable{out: w}
+}
+
+func (w *NonColorable) Write(data []byte) (n int, err error) {
+	er := bytes.NewBuffer(data)
+loop:
+	for {
+		c1, _, err := er.ReadRune()
+		if err != nil {
+			break loop
+		}
+		if c1 != 0x1b {
+			fmt.Fprint(w.out, string(c1))
+			continue
+		}
+		c2, _, err := er.ReadRune()
+		if err != nil {
+			w.lastbuf.WriteRune(c1)
+			break loop
+		}
+		if c2 != 0x5b {
+			w.lastbuf.WriteRune(c1)
+			w.lastbuf.WriteRune(c2)
+			continue
+		}
+
+		var buf bytes.Buffer
+		for {
+			c, _, err := er.ReadRune()
+			if err != nil {
+				w.lastbuf.WriteRune(c1)
+				w.lastbuf.WriteRune(c2)
+				w.lastbuf.Write(buf.Bytes())
+				break loop
+			}
+			if ('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z') || c == '@' {
+				break
+			}
+			buf.Write([]byte(string(c)))
+		}
+	}
+	return len(data) - w.lastbuf.Len(), nil
+}