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Eslint参考手册

规则 | Rules

comma-spacing

--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。

逗号周围的间距提高了项目列表的可读性。尽管大多数语言的样式准则规定在逗号之后添加一个空格,但不在其之前,这对项目的偏好是主观的。

var foo = 1, bar = 2;
var foo = 1 ,bar = 2;

规则细节

规则在变量声明,数组文字,对象文字,函数参数和序列中的逗号前后加上一致的间距。

这条规则不适用的ArrayExpressionArrayPattern在以下任一情况:

  • 相邻的空元素
  • 一个初始的 null 元素,以避免与array-bracket-spacing规则冲突

选项

规则有一个对象选项:

  • "before": false (默认)在逗号前不允许有空格
  • "before": true 在逗号前需要一个或多个空格
  • "after": true (默认)在逗号后需要一个或多个空格
  • "after": false 逗号后不允许有空格

after

{ "before": false, "after": true }规则的默认选项的代码错误示例:

/*eslint comma-spacing: ["error", { "before": false, "after": true }]*/

var foo = 1 ,bar = 2;
var arr = [1 , 2];
var obj = {"foo": "bar" ,"baz": "qur"};
foo(a ,b);
new Foo(a ,b);
function foo(a ,b){}
a ,b

具有默认选项的{ "before": false, "after": true }规则的正确代码示例:

/*eslint comma-spacing: ["error", { "before": false, "after": true }]*/

var foo = 1, bar = 2
    , baz = 3;
var arr = [1, 2];
var arr = [1,, 3]
var obj = {"foo": "bar", "baz": "qur"};
foo(a, b);
new Foo(a, b);
function foo(a, b){}
a, b

{ "before": false, "after": true }规则的正确代码示例,默认选项为初始 null 元素:

/*eslint comma-spacing: ["error", { "before": false, "after": true }]*/
/*eslint array-bracket-spacing: ["error", "always"]*/

var arr = [ , 2, 3 ]

before

{ "before": true, "after": false }规则的代码错误代码示例如下:

/*eslint comma-spacing: ["error", { "before": true, "after": false }]*/

var foo = 1, bar = 2;
var arr = [1 , 2];
var obj = {"foo": "bar", "baz": "qur"};
new Foo(a,b);
function foo(a,b){}
a, b

{ "before": true, "after": false }规则的正确代码示例包含以下选项:

/*eslint comma-spacing: ["error", { "before": true, "after": false }]*/

var foo = 1 ,bar = 2 ,
    baz = true;
var arr = [1 ,2];
var arr = [1 ,,3]
var obj = {"foo": "bar" ,"baz": "qur"};
foo(a ,b);
new Foo(a ,b);
function foo(a ,b){}
a ,b

{ "before": true, "after": false }规则的正确代码示例,其中包含以下选项的初始空元素:

/*eslint comma-spacing: ["error", { "before": true, "after": false }]*/
/*eslint array-bracket-spacing: ["error", "never"]*/

var arr = [,2 ,3]

何时不使用它

如果您的项目不符合一致的逗号间隔模式,请关闭此规则。

进一步阅读

  • Javascript
  • Dojo Style Guide

相关规则

  • array-bracket-spacing
  • comma-style
  • space-in-brackets (deprecated)
  • space-in-parens
  • space-infix-ops
  • space-after-keywords
  • space-unary-ops
  • space-return-throw-case

版本

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