Add PrefixColorOption

main.go

@@ -50,6 +50,7 @@ func main() {
 		completer,
 		prompt.MaxCompletionsOption(8),
 		prompt.PrefixOption(">>> "),
+		prompt.PrefixColorOption("blue"),
 		prompt.TitleOption("Hello! this is prompt toolkit"),
 	)
 	defer fmt.Println("\nGoodbye!")

prompt/option.go

@@ -27,7 +27,14 @@ func TitleOption(x string) option {
 
 func PrefixOption(x string) option {
 	return func(p *Prompt) error {
-		p.renderer.Prefix = x
+		p.renderer.prefix = x
+		return nil
+	}
+}
+
+func PrefixColorOption(x string) option {
+	return func(p *Prompt) error {
+		p.renderer.prefixColor = x
 		return nil
 	}
 }
@@ -43,8 +50,9 @@ func NewPrompt(executor Executor, completer Completer, opts ...option) *Prompt {
 	pt := &Prompt{
 		in: &VT100Parser{fd: syscall.Stdin},
 		renderer: &Render{
-			Prefix:         "> ",
-			out:            &VT100Writer{fd: syscall.Stdout},
+			prefix:      "> ",
+			prefixColor: "green",
+			out:         &VT100Writer{fd: syscall.Stdout},
 		},
 		title:     "",
 		buf:       NewBuffer(),

prompt/render.go

@@ -1,7 +1,8 @@
 package prompt
 
 type Render struct {
-	Prefix         string
+	prefix         string
+	prefixColor    string
 	Title          string
 	out            ConsoleWriter
 	row            uint16
@@ -18,8 +19,8 @@ func (r *Render) Setup() {
 }
 
 func (r *Render) renderPrefix() {
-	r.out.SetColor("green", "default")
-	r.out.WriteStr(r.Prefix)
+	r.out.SetColor(r.prefixColor, "default")
+	r.out.WriteStr(r.prefix)
 	r.out.SetColor("default", "default")
 }
 
@@ -56,11 +57,11 @@ func (r *Render) renderCompletion(buf *Buffer, words []string, chosen int) {
 		}
 	}
 
-	formatted, width := formatCompletions(words, int(r.col) - len(r.Prefix) - 3)
+	formatted, width := formatCompletions(words, int(r.col) - len(r.prefix) - 3)
 	l := len(formatted)
 	r.prepareArea(l)
 
-	d := (len(r.Prefix) + len(buf.Document().TextBeforeCursor())) % int(r.col)
+	d := (len(r.prefix) + len(buf.Document().TextBeforeCursor())) % int(r.col)
 	if d + width + 3 > int(r.col) {
 		r.out.CursorBackward(d + width + 3 - int(r.col))
 	}