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Eslint参考手册

规则 | Rules

max-statements-per-line

包含太多语句的代码行可能难以阅读。代码通常从上到下读取,特别是在扫描时,所以限制单行允许的语句数量对于可读性和可维护性非常有利。

function () { var bar; if (condition) { bar = 1; } else { bar = 2; } return true; } // too many statements

规则细节

此规则强制每行允许的最大语句数。

选项

max

“max”对象属性是可选的(默认值:1)。

此规则的默认代码错误代码示例{ "max": 1 }

/*eslint max-statements-per-line: ["error", { "max": 1 }]*/

var bar; var baz;
if (condition) { bar = 1; }
for (var i = 0; i < length; ++i) { bar = 1; }
switch (discriminant) { default: break; }
function foo() { bar = 1; }
var foo = function foo() { bar = 1; };
(function foo() { bar = 1; })();

具有默认选项的此规则的正确代码示例{ "max": 1 }

/*eslint max-statements-per-line: ["error", { "max": 1 }]*/

var bar, baz;
if (condition) bar = 1;
for (var i = 0; i < length; ++i);
switch (discriminant) { default: }
function foo() { }
var foo = function foo() { };
(function foo() { })();

此规则的错误代码示例包含以下{ "max": 2 }选项:

/*eslint max-statements-per-line: ["error", { "max": 2 }]*/

var bar; var baz; var qux;
if (condition) { bar = 1; } else { baz = 2; }
for (var i = 0; i < length; ++i) { bar = 1; baz = 2; }
switch (discriminant) { case 'test': break; default: break; }
function foo() { bar = 1; baz = 2; }
var foo = function foo() { bar = 1; };
(function foo() { bar = 1; baz = 2; })();

此规则的正确代码示例包含以下{ "max": 2 }选项:

/*eslint max-statements-per-line: ["error", { "max": 2 }]*/

var bar; var baz;
if (condition) bar = 1; if (condition) baz = 2;
for (var i = 0; i < length; ++i) { bar = 1; }
switch (discriminant) { default: break; }
function foo() { bar = 1; }
var foo = function foo() { bar = 1; };
(function foo() { var bar = 1; })();

何时不使用它

如果您不关心每行上的语句数量,则可以关闭此规则。

相关规则

  • max-depth
  • max-len
  • max-nested-callbacks
  • max-params
  • max-statements

版本

这条规则是在ESLint 2.5.0中引入的。

资源

  • 规则来源
  • 文档来源

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.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。

主页 https://eslint.org/
源码 https://github.com/eslint/eslint
发布版本 4.12.0

Eslint目录

1.指南 | Guide
2.规则 | Rules