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Eslint参考手册

规则 | Rules

space-in-parens

--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。

一些风格指南需要或不允许使用括号内的空格:

foo( 'bar' );
var x = ( 1 + 2 ) * 3;

foo('bar');
var x = (1 + 2) * 3;

规则细节

此规则将强制直接在括号内进行间隔的一致性,即禁止或要求右侧(和左侧有一个或多个空格)。无论如何,()仍然会被允许。

选项

该规则有两种选择:

  • "never" (默认)在圆括号内强制使用零空格
  • "always" 在括号内强制使用空格

根据您的编码惯例,您可以通过在您的配置中指定它来选择任一选项:

"space-in-parens": ["error", "always"]

“never”

此规则的默认"never"代码错误代码示例:

/*eslint space-in-parens: ["error", "never"]*/

foo( 'bar');
foo('bar' );
foo( 'bar' );

var foo = ( 1 + 2 ) * 3;
( function () { return 'bar'; }() );

具有默认选项的此规则的正确代码示例"never"

/*eslint space-in-parens: ["error", "never"]*/

foo();

foo('bar');

var foo = (1 + 2) * 3;
(function () { return 'bar'; }());

“always”

此规则的错误代码示例包含以下"always"选项:

/*eslint space-in-parens: ["error", "always"]*/

foo( 'bar');
foo('bar' );
foo('bar');

var foo = (1 + 2) * 3;
(function () { return 'bar'; }());

此规则的正确代码示例包含以下"always"选项:

/*eslint space-in-parens: ["error", "always"]*/

foo();

foo( 'bar' );

var foo = ( 1 + 2 ) * 3;
( function () { return 'bar'; }() );

例外

对象字面量可以用作第三个数组项来指定异常,将键"exceptions"和数组作为值。这些例外在第一种选择的情况下起作用。也就是说,如果"always"设置为强制间隔,那么任何“例外”都将禁止间距。相反,如果"never"设置为禁止间隔,则任何“例外”都会强制间隔。

以下例外情况可供使用:["{}", "[]", "()", "empty"]

此规则的错误代码示例包含以下"never", { "exceptions": ["{}"] }选项:

/*eslint space-in-parens: ["error", "never", { "exceptions": ["{}"] }]*/

foo({bar: 'baz'});
foo(1, {bar: 'baz'});

此规则的正确代码示例包含以下"never", { "exceptions": ["{}"] }选项:

/*eslint space-in-parens: ["error", "never", { "exceptions": ["{}"] }]*/

foo( {bar: 'baz'} );
foo(1, {bar: 'baz'} );

此规则的错误代码示例包含以下"always", { "exceptions": ["{}"] }选项:

/*eslint space-in-parens: ["error", "always", { "exceptions": ["{}"] }]*/

foo( {bar: 'baz'} );
foo( 1, {bar: 'baz'} );

此规则的正确代码示例包含以下"always", { "exceptions": ["{}"] }选项:

/*eslint space-in-parens: ["error", "always", { "exceptions": ["{}"] }]*/

foo({bar: 'baz'});
foo( 1, {bar: 'baz'});

此规则的错误代码示例包含以下"never", { "exceptions": ["[]"] }选项:

/*eslint space-in-parens: ["error", "never", { "exceptions": ["[]"] }]*/

foo([bar, baz]);
foo([bar, baz], 1);

此规则的正确代码示例包含以下"never", { "exceptions": ["[]"] }选项:

/*eslint space-in-parens: ["error", "never", { "exceptions": ["[]"] }]*/

foo( [bar, baz] );
foo( [bar, baz], 1);

此规则的错误代码示例包含以下"always", { "exceptions": ["[]"] }选项:

/*eslint space-in-parens: ["error", "always", { "exceptions": ["[]"] }]*/

foo( [bar, baz] );
foo( [bar, baz], 1 );

此规则的正确代码示例包含以下"always", { "exceptions": ["[]"] }选项:

/*eslint space-in-parens: ["error", "always", { "exceptions": ["[]"] }]*/

foo([bar, baz]);
foo([bar, baz], 1 );

此规则的错误代码示例包含以下"never", { "exceptions": ["()"] }]选项:

/*eslint space-in-parens: ["error", "never", { "exceptions": ["()"] }]*/

foo((1 + 2));
foo((1 + 2), 1);

此规则的正确代码示例包含以下"never", { "exceptions": ["()"] }]选项:

/*eslint space-in-parens: ["error", "never", { "exceptions": ["()"] }]*/

foo( (1 + 2) );
foo( (1 + 2), 1);

此规则的错误代码示例包含以下"always", { "exceptions": ["()"] }]选项:

/*eslint space-in-parens: ["error", "always", { "exceptions": ["()"] }]*/

foo( ( 1 + 2 ) );
foo( ( 1 + 2 ), 1 );

此规则的正确代码示例包含以下"always", { "exceptions": ["()"] }]选项:

/*eslint space-in-parens: ["error", "always", { "exceptions": ["()"] }]*/

foo(( 1 + 2 ));
foo(( 1 + 2 ), 1 );

"empty"例外是空括号,并以同样的方式与其他异常,反转的第一个选项。

此规则的错误代码示例包含以下"never", { "exceptions": ["empty"] }]选项:

/*eslint space-in-parens: ["error", "never", { "exceptions": ["empty"] }]*/

foo();

此规则的正确代码示例包含以下"never", { "exceptions": ["empty"] }]选项:

/*eslint space-in-parens: ["error", "never", { "exceptions": ["empty"] }]*/

foo( );

此规则的错误代码示例包含以下"always", { "exceptions": ["empty"] }]选项:

/*eslint space-in-parens: ["error", "always", { "exceptions": ["empty"] }]*/

foo( );

此规则的正确代码示例包含以下"always", { "exceptions": ["empty"] }]选项:

/*eslint space-in-parens: ["error", "always", { "exceptions": ["empty"] }]*/

foo();

您可以在"exceptions"数组中包含多个条目。

此规则的错误代码示例包含以下"always", { "exceptions": ["{}", "[]"] }]选项:

/*eslint space-in-parens: ["error", "always", { "exceptions": ["{}", "[]"] }]*/

bar( {bar:'baz'} );
baz( 1, [1,2] );
foo( {bar: 'baz'}, [1, 2] );

此规则的正确代码示例包含以下"always", { "exceptions": ["{}", "[]"] }]选项:

/*eslint space-in-parens: ["error", "always", { "exceptions": ["{}", "[]"] }]*/

bar({bar:'baz'});
baz( 1, [1,2]);
foo({bar: 'baz'}, [1, 2]);

何时不使用

如果不关心圆括号间距的一致性,可以关闭此规则。

相关规则

  • 括号中的空格(不建议使用)版本此规则是在ESLint 0.8.0.Resources中引入的
  • 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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发布版本 4.12.0

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1.指南 | Guide
2.规则 | Rules