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Eslint参考手册

规则 | Rules

no-multi-spaces

--fix命令行上的选项可以自动修复一些被这条规则反映的问题。

连续多个不用于缩进的空格通常是错误。例如:

if(foo  === "bar") {}

很难说,但是foo===之间有两个空格。像这样的多个空间通常被赞成单个空间而不赞成:

if(foo === "bar") {}

规则细节

规则旨在禁止在逻辑表达式,条件表达式,声明,数组元素,对象属性,序列和函数参数周围使用多个空格。

规则的错误代码示例:

/*eslint no-multi-spaces: "error"*/

var a =  1;

if(foo   === "bar") {}

a <<  b

var arr = [1,  2];

a ?  b: c

规则的正确代码示例:

/*eslint no-multi-spaces: "error"*/

var a = 1;

if(foo === "bar") {}

a << b

var arr = [1, 2];

a ? b: c

选项

规则的配置由具有以下属性的对象组成:

  • "ignoreEOLComments": true(默认为false)会在行尾出现注释之前忽略多个空格
  • "exceptions": { "Property": true }"Property"是默认指定的唯一节点)指定要忽略的节点

ignoreEOLComments

使用(默认)选项对{ "ignoreEOLComments": false }规则进行错误代码的示例:

/*eslint no-multi-spaces: ["error", { ignoreEOLComments: false }]*/

var x = 5;      // comment
var x = 5;      /* multiline
 * comment
 */

{ "ignoreEOLComments": false }(默认)选项的正确代码示例:

/*eslint no-multi-spaces: ["error", { ignoreEOLComments: false }]*/

var x = 5; // comment
var x = 5; /* multiline
 * comment
 */

{ "ignoreEOLComments": true }规则的正确代码示例包含以下选项:

/*eslint no-multi-spaces: ["error", { ignoreEOLComments: true }]*/

var x = 5; // comment
var x = 5;      // comment
var x = 5; /* multiline
 * comment
 */
var x = 5;      /* multiline
 * comment
 */

例外

为了避免与需要多个空间的其他规则相矛盾,此规则可以通过exceptions选项忽略某些节点。

选项是一个期望属性名称为ESTree定义的AST节点类型的对象。确定节点类型exceptions的最简单方法是使用在线演示。

只有Property节点类型在默认情况下被忽略,因为对于键间距规则,一些对齐选项在对象文字的属性中需要多个空格。

"exceptions": { "Property": true }默认选项的正确代码示例:

/*eslint no-multi-spaces: "error"*/
/*eslint key-spacing: ["error", { align: "value" }]*/

var obj = {
    first:  "first",
    second: "second"
};

"exceptions": { "Property": false }选项的错误代码示例:

/*eslint no-multi-spaces: ["error", { exceptions: { "Property": false } }]*/
/*eslint key-spacing: ["error", { align: "value" }]*/

var obj = {
    first:  "first",
    second: "second"
};

"exceptions": { "BinaryExpression": true }选项的正确代码示例:

/*eslint no-multi-spaces: ["error", { exceptions: { "BinaryExpression": true } }]*/

var a = 1  *  2;

"exceptions": { "VariableDeclarator": true }选项的正确代码示例:

/*eslint no-multi-spaces: ["error", { exceptions: { "VariableDeclarator": true } }]*/

var someVar      = 'foo';
var someOtherVar = 'barBaz';

"exceptions": { "ImportDeclaration": true }选项的正确代码示例:

/*eslint no-multi-spaces: ["error", { exceptions: { "ImportDeclaration": true } }]*/

import mod          from 'mod';
import someOtherMod from 'some-other-mod';

何时不使用它

如果你不想检查和禁止多个空格,那么你应该关闭这个规则。

相关规则

  • key-spacing
  • space-infix-ops
  • space-in-brackets (deprecated)
  • space-in-parens
  • space-after-keywords
  • space-unary-ops
  • space-return-throw-case

版本

该规则在ESLint 0.9.0中引入。

资源

  • Rule source
  • Documentation source

规则 | Rules相关

1.accessor-pairs
2.array-bracket-newline
3.array-bracket-spacing
4.array-callback-return
5.array-element-newline
6.arrow-body-style
7.arrow-parens
8.arrow-spacing
9.block-scoped-var
10.block-spacing
11.brace-style
12.callback-return
13.camelcase
14.capitalized-comments
15.class-methods-use-this
16.comma-dangle
17.comma-spacing
18.comma-style
19.complexity
20.computed-property-spacing
21.consistent-return
22.consistent-this
23.constructor-super
24.curly
25.default-case
26.dot-location
27.dot-notation
28.eol-last
29.eqeqeq
30.for-direction
31.func-call-spacing
32.func-name-matching
33.func-names
34.func-style
35.function-paren-newline
36.generator-star
37.generator-star-spacing
38.getter-return
39.global-require
40.global-strict
41.guard-for-in
42.handle-callback-err
43.id-blacklist
44.id-length
45.id-match
46.implicit-arrow-linebreak
47.indent
48.indent-legacy
49.init-declarations
50.jsx-quotes
51.key-spacing
52.keyword-spacing
53.line-comment-position
54.linebreak-style
55.lines-around-comment
56.lines-around-directive
57.lines-between-class-members
58.max-depth
59.max-len
60.max-lines
61.max-nested-callbacks
62.max-params
63.max-statements
64.max-statements-per-line
65.multiline-comment-style
66.multiline-ternary
67.new-cap
68.new-parens
69.newline-after-var
70.newline-before-return
71.newline-per-chained-call
72.no-alert
73.no-array-constructor
74.no-arrow-condition
75.no-await-in-loop
76.no-bitwise
77.no-buffer-constructor
78.no-caller
79.no-case-declarations
80.no-catch-shadow
81.no-class-assign
82.no-comma-dangle
83.no-compare-neg-zero
84.no-cond-assign
85.no-confusing-arrow
86.no-console
87.no-const-assign
88.no-constant-condition
89.no-continue
90.no-control-regex
91.no-debugger
92.no-delete-var
93.no-div-regex
94.no-dupe-args
95.no-dupe-class-members
96.no-dupe-keys
97.no-duplicate-case
98.no-duplicate-imports
99.no-else-return
100.no-empty
Eslint

ESLint 是一个代码规范和错误检查工具,有以下几个特性。所有东西都是可以插拔的。你可以调用任意的 rule api 或者 formatter api 去打包或者定义 rule or formatter。任意的 rule 都是独立的。没有特定的 coding style,你可以自己配置。

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2.规则 | Rules