noUnusedFunctionParameters

JavaScript (and super languages)

摘要

¥Summary

规则生效日期：v1.8.0

¥Rule available since: v1.8.0
诊断类别：lint/correctness/noUnusedFunctionParameters

¥Diagnostic Category: lint/correctness/noUnusedFunctionParameters
此规则为推荐规则，默认启用。

¥This rule is recommended, which means is enabled by default.
此规则包含 unsafe 修复程序。

¥This rule has an unsafe fix.
此规则的默认严重级别为 warning。

¥The default severity of this rule is warning.

如何配置

¥How to configure

1
{
2
  "linter": {
3
    "rules": {
4
      "correctness": {
5
        "noUnusedFunctionParameters": "error"
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      }
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    }
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  }
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}

描述

¥Description

禁止未使用的函数参数。

¥Disallow unused function parameters.

此规则有一个例外：以下划线开头的参数，例如 function foo(_a, _b) {}。

¥There is an exception to this rule: parameters that starts with underscore, e.g. function foo(_a, _b) {}.

示例

¥Examples

无效

¥Invalid

1
function foo(myVar) {
2
    console.log('foo');
3
}

code-block.js:1:14 lint/correctness/noUnusedFunctionParameters  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ⚠ This parameter is unused.
  
  > 1 │ function foo(myVar) {
      │              ^^^^^
    2 │     console.log(‘foo’);
    3 │ }
  
  ℹ Unused parameters might be the result of an incomplete refactoring.
  
  ℹ Unsafe fix: If this is intentional, prepend myVar with an underscore.
  
    1   │ - function·foo(myVar)·{
      1 │ + function·foo(_myVar)·{
    2 2 │       console.log(‘foo’);
    3 3 │   }

1
new Promise((accept, reject) => {
2
    window.setTimeout(accept, 1000);
3
});

code-block.js:1:22 lint/correctness/noUnusedFunctionParameters  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ⚠ This parameter is unused.
  
  > 1 │ new Promise((accept, reject) => {
      │                      ^^^^^^
    2 │     window.setTimeout(accept, 1000);
    3 │ });
  
  ℹ Unused parameters might be the result of an incomplete refactoring.
  
  ℹ Unsafe fix: If this is intentional, prepend reject with an underscore.
  
    1   │ - new·Promise((accept,·reject)·=>·{
      1 │ + new·Promise((accept,·_reject)·=>·{
    2 2 │       window.setTimeout(accept, 1000);
    3 3 │   });

1
const squares = [[1, 1], [2, 4], [3, 9], [4, 16]];
2
squares.filter(([k, v]) => v > 5);

code-block.js:2:18 lint/correctness/noUnusedFunctionParameters  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ⚠ This parameter is unused.
  
    1 │ const squares = [[1, 1], [2, 4], [3, 9], [4, 16]];
  > 2 │ squares.filter(([k, v]) => v > 5);
      │                  ^
    3 │ 
  
  ℹ Unused parameters might be the result of an incomplete refactoring.
  
  ℹ Unsafe fix: If this is intentional, prepend k with an underscore.
  
    1 1 │   const squares = [[1, 1], [2, 4], [3, 9], [4, 16]];
    2   │ - squares.filter(([k,·v])·=>·v·>·5);
      2 │ + squares.filter(([_k,·v])·=>·v·>·5);
    3 3 │

有效

¥Valid

1
function foo(myVar) {
2
    console.log(myVar);
3
}

1
function withObjectSpread({ a, ...rest }) {
2
       return rest;
3
}

选项

¥Options

该规则具有以下选项

¥The rule has the following options

`ignoreRestSiblings`

自 v2.1.0 版本起：

¥Since v2.1.0

是否忽略使用扩展符解构对象的未使用变量。示例：当 function({ a, b, ...rest }) { return rest;} 中的 a 和 b 设置为 false 时，此规则应忽略它们。

¥Whether to ignore unused variables from an object destructuring with a spread. Example: a and b in function({ a, b, ...rest }) { return rest;} should be ignored by this rule when set to false.

默认为 true。

¥Defaults to true.

1
{
2
  "linter": {
3
    "rules": {
4
      "correctness": {
5
        "noUnusedFunctionParameters": {
6
          "options": {
7
            "ignoreRestSiblings": false
8
          }
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        }
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      }
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    }
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  }
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}

1
function withObjectSpread({ b, ...rest }) {
2
       return rest;
3
}

code-block.js:1:29 lint/correctness/noUnusedFunctionParameters ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ⚠ This parameter is unused.
  
  > 1 │ function withObjectSpread({ b, …rest }) {
      │                             ^
    2 │        return rest;
    3 │ }
  
  ℹ Unused parameters might be the result of an incomplete refactoring.

noUnusedFunctionParameters

摘要

如何配置

描述

示例

无效

有效

选项

ignoreRestSiblings

相关链接

`ignoreRestSiblings`