如何避免 eslint 规则 no-unneeded-ternary violation：'Unnecessary use of conditional expression for default assignment'

Question

这是我的代码

class Message extends Component {

  render() {
    const { message, timeToRedirect } = this.props;
    const time = timeToRedirect ? timeToRedirect : TIME_TO_REDIRECT  // eslint flags this line

思路是，如果参数timeToRedirect为零或未定义，我会把常量TIME_TO_REDIRECT赋值给变量time

但是 eslint 将此标记为违反规则 no-unneeded-ternary：'Unnecessary use of conditional expression for default assignment'.

我当然可以改写成

let time = timeToRedirect;
if (!timeToRedirect) {
   time = TIME_TO_REDIRECT;
 }

但我认为它不够优雅。

有没有更好的方法重写三元表达式？

我目前正在使用这些 npm 包

"babel-eslint": "7.1.0",
"eslint": "3.9.1",
"eslint-config-airbnb": "12.0.0",
"eslint-plugin-import": "1.16.0",
"eslint-plugin-jsx-a11y": "2.2.3",
"eslint-plugin-react": "6.5.0",

Answer 1

They want you to use the OR operator:

const time = timeToRedirect || TIME_TO_REDIRECT;

请注意，要捕获 undefined 值，您还可以在解构中使用默认初始化程序：

render() {
    const { message, timeToRedirect: time = TIME_TO_REDIRECT } = this.props;
    …

如何避免 eslint 规则 no-unneeded-ternary violation：'Unnecessary use of conditional expression for default assignment'

How to avoid eslint rule no-unneeded-ternary violation: 'Unnecessary use of conditional expression for default assignment'

ecmascript-6

eslint

eslint-config-airbnb