no-unsafe-optional-chaining
不允许在不允许 undefined
值的上下文中使用可选链接
配置文件 中的
"extends": "eslint:recommended"
属性启用了该规则
可选链接 (?.
) 表达式可以短路,返回值 undefined
。因此,将评估的可选链接表达式视为函数、对象、数字等,可能会导致 TypeError 或意外结果。例如:
var obj = undefined;
1 in obj?.foo; // TypeError
with (obj?.foo); // TypeError
for (bar of obj?.foo); // TypeError
bar instanceof obj?.foo; // TypeError
const { bar } = obj?.foo; // TypeError
此外,括号限制了链中短路的范围。例如:
var obj = undefined;
(obj?.foo)(); // TypeError
(obj?.foo).bar; // TypeError
规则详情
此规则旨在检测使用可选链接无法防止运行时错误的某些情况。特别是,它在短路到 undefined
导致之后抛出 TypeError 的位置标记可选链接表达式。
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/*eslint no-unsafe-optional-chaining: "error"*/
(obj?.foo)();
(obj?.foo).bar;
(foo?.()).bar;
(foo?.()).bar();
(obj?.foo ?? obj?.bar)();
(foo || obj?.foo)();
(obj?.foo && foo)();
(foo ? obj?.foo : bar)();
(foo, obj?.bar).baz;
(obj?.foo)`template`;
new (obj?.foo)();
[...obj?.foo];
bar(...obj?.foo);
1 in obj?.foo;
bar instanceof obj?.foo;
for (bar of obj?.foo);
const { bar } = obj?.foo;
[{ bar } = obj?.foo] = [];
with (obj?.foo);
class A extends obj?.foo {}
var a = class A extends obj?.foo {};
async function foo () {
const { bar } = await obj?.foo;
(await obj?.foo)();
(await obj?.foo).bar;
}
9yoNpjr6gd6zh0cwZMnzCpDrCM6/zTdrRqXIvlUhfaHsSeCWilcYpPgpMZ09hE80
/*eslint no-unsafe-optional-chaining: "error"*/
(obj?.foo)?.();
obj?.foo();
(obj?.foo ?? bar)();
obj?.foo.bar;
obj.foo?.bar;
foo?.()?.bar;
(obj?.foo ?? bar)`template`;
new (obj?.foo ?? bar)();
var baz = {...obj?.foo};
const { bar } = obj?.foo || baz;
async function foo () {
const { bar } = await obj?.foo || baz;
(await obj?.foo)?.();
(await obj?.foo)?.bar;
}
选项
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- oFbDAgjQsKL58IfJCWRuO4UTV8MqsvfyfZH5/h5AxVWdbHi0DN0wNGtNYCTxVIHkwNp/EEL32aQqA8J9AhSwReWeS/vgnusRKWMmILzoryxGDwdSadGNAFSwx92uTFNtdauXCktLTO0O4ePwZDUqV8JRYmI9cdACRiqE8UrdeyfsnlmRss0L1FVkrUjbzlkPi5ItyAHiRrMbEyw1LjXbe8f93ZZe5SPbFNWgZ3uCozr6vZOx0ilALIUa6cJFIvcMKEPyR6bUlBzw5LJnOXymTFB7FoM+jYgvp0O4Nc6oEhmiS4/8KdP+gU6eP9dXqzbq2OL0adS6G8f6a73/ABu5kZb0RLbrgaT1S8NCI0U5nvA=
disallowArithmeticOperators
xZ+A4Fw/Hknk3Rm9fufX9wv2NKx6k7o0WbbixxTp0PZ7dDP4O4OVKIop9jKPj2/N4SCbFdU1XbQrS/PcfSCi0WFNX/dq9ts1DU59AgaNRdmYKIWpzTVnD9QFyoxZ2cnz
- 9ZpWZxmWXIlsT0lA7jh0vKm0ATOnpKtaUiKKarI+V7Bn+xIxI+x/UpxXY2p1hy1N3fmdWQIMb4BOd5+V5sJqULFSaDJSpsM6R38lvZxyCW34haLhDIZU27WSo7aAH99taqb5MnCQZW4ZNS/cEX97aNviOkIsZklhCGLKfTktP5+6vHClLeaTTjyugeh0U1kC4i+Zs+FVD5lbwGF91YiuDbrEeAbk3PQ7y+icqPHAebZRPYuDdWj9Ru3rG/5IzrbxdIbmYQGtgZZATVGwu4h04EkZHfmlqBk+9QmaE5JQ6FEWoX4F7W5RItaXFzVnsQAa3XExp/O9QI4CsQ8PE+frdSS+k5h7O50Yu/5YydDUK22rg+QLzSPIK+puupjTAbpwNP1igitaTQ2T2TZJiejp1eMjPALk20Vsx+HqhSxjO1HJY3PlH0+4gZ8D7FfVg/uP
+WNthHaG78UucD9Wr3O8vwpT70OivdmmaCRkmrbnK+UKmfsV6ozpu8G/v7TY4ND7w1JyIn5Q/uAsZCI96TS6zOVWRdgXWI7BMnj77yHXay7NkJ4gxm9CaVJRfTlgQ26sDr0PRpW5Qu10l8Y4gXR+Pw==
/*eslint no-unsafe-optional-chaining: ["error", { "disallowArithmeticOperators": true }]*/
+obj?.foo;
-obj?.foo;
obj?.foo + bar;
obj?.foo - bar;
obj?.foo / bar;
obj?.foo * bar;
obj?.foo % bar;
obj?.foo ** bar;
baz += obj?.foo;
baz -= obj?.foo;
baz /= obj?.foo;
baz *= obj?.foo;
baz %= obj?.foo;
baz **= obj?.foo;
async function foo () {
+await obj?.foo;
await obj?.foo + bar;
baz += await obj?.foo;
}