Golang测试标准输出(Golang test stdout)

Golang测试标准输出(Golang test stdout)

我试图测试打印ANSI转义码的一些函数。 例如

// Print a line in a color func PrintlnColor(color string, a ...interface{}) { fmt.Print("\x1b[31m") fmt.Print(a...) fmt.Println("\x1b[0m") }

我尝试使用示例来做到这一点，但他们似乎不喜欢转义码。

有什么方法可以测试写入stdout的内容吗？

I am trying to test some functions that print ANSI escape codes. e.g.

// Print a line in a color func PrintlnColor(color string, a ...interface{}) { fmt.Print("\x1b[31m") fmt.Print(a...) fmt.Println("\x1b[0m") }

I tried using Examples to do it, but they don't seem to like escape codes.

Is there any way to test what is written to stdout?

最满意答案

使用fmt.Fprint打印到io.Writer可以控制输出的写入位置。

var out io.Writer = os.Stdout func main() { // write to Stdout PrintlnColor("foo") buf := &bytes.Buffer{} out = buf // write to buffer PrintlnColor("foo") fmt.Println(buf.String()) } // Print a line in a color func PrintlnColor(a ...interface{}) { fmt.Fprint(out, "\x1b[31m") fmt.Fprint(out, a...) fmt.Fprintln(out, "\x1b[0m") }

去玩

Using fmt.Fprint to print to io.Writer lets you control where the output is written.

var out io.Writer = os.Stdout func main() { // write to Stdout PrintlnColor("foo") buf := &bytes.Buffer{} out = buf // write to buffer PrintlnColor("foo") fmt.Println(buf.String()) } // Print a line in a color func PrintlnColor(a ...interface{}) { fmt.Fprint(out, "\x1b[31m") fmt.Fprint(out, a...) fmt.Fprintln(out, "\x1b[0m") }

Go play