valid-typeof
强制将 typeof 表达式与有效字符串进行比较
在 配置文件 中使用来自 @eslint/js 的 recommended 配置可以启用此规则
此规则报告的一些问题可通过编辑器 建议 手动修复
对于绝大多数用例，typeof 运算符的结果是以下字符串字面之一："undefined"、"object"、"boolean"、"number"、"string"、"function"、"symbol" 和 "bigint"。将 typeof 运算符的结果与其他字符串字面进行比较通常是输入错误。
¥For a vast majority of use cases, the result of the typeof operator is one of the following string literals: "undefined", "object", "boolean", "number", "string", "function", "symbol", and "bigint". It is usually a typing mistake to compare the result of a typeof operator to other string literals.
规则详情
¥Rule Details
此规则强制将 typeof 表达式与有效的字符串字面进行比较。
¥This rule enforces comparing typeof expressions to valid string literals.
此规则的错误代码示例：
¥Examples of incorrect code for this rule:
/*eslint valid-typeof: "error"*/
typeof foo === "strnig"
typeof foo == "undefimed"
typeof bar != "nunber"
typeof bar !== "fucntion"
此规则的正确代码示例：
¥Examples of correct code for this rule:
/*eslint valid-typeof: "error"*/
typeof foo === "string"
typeof bar == "undefined"
typeof foo === baz
typeof bar === typeof qux
选项
¥Options
此规则有一个对象选项：
¥This rule has an object option:
-
"requireStringLiterals": true允许将typeof表达式仅与字符串字面量或其他typeof表达式进行比较，并且不允许与任何其他值进行比较。默认为false。¥
"requireStringLiterals": trueallows the comparison oftypeofexpressions with only string literals or othertypeofexpressions, and disallows comparisons to any other value. Default isfalse.
requireStringLiterals
使用 { "requireStringLiterals": true } 选项的错误代码示例：
¥Examples of incorrect code with the { "requireStringLiterals": true } option:
/*eslint valid-typeof: ["error", { "requireStringLiterals": true }]*/
typeof foo === undefined
typeof bar == Object
typeof baz === "strnig"
typeof qux === "some invalid type"
typeof baz === anotherVariable
typeof foo == 5
使用 { "requireStringLiterals": true } 选项的正确代码示例：
¥Examples of correct code with the { "requireStringLiterals": true } option:
/*eslint valid-typeof: ["error", { "requireStringLiterals": true }]*/
typeof foo === "undefined"
typeof bar == "object"
typeof baz === "string"
typeof bar === typeof qux
何时不使用
¥When Not To Use It
如果你将在主机对象上使用 typeof 运算符，你可能需要关闭此规则。
¥You may want to turn this rule off if you will be using the typeof operator on host objects.
版本
此规则是在 ESLint v0.5.0 中引入。