useArraySome

JavaScript (and super languages)

Caution

This rule is part of the nursery group. This means that it is experimental and the behavior can change at any time.

Summary

• Rule available since: v2.4.5
• Diagnostic Category: lint/nursery/useArraySome
• This rule has an unsafe fix.
• The default severity of this rule is information.
• Sources:
  • Inspired from unicorn/prefer-array-some

How to configure

biome.json

{
  "linter": {
    "rules": {
      "nursery": {
        "useArraySome": "error"
      }
    }
  }
}

Description

Prefer Array.prototype.some() over verbose existence checks.

Examples

Invalid

array.filter(predicate).length > 0;

code-block.js:1:1 lint/nursery/useArraySome  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ℹ This expression uses .filter() and then checks whether the result is empty.
  
  > 1 │ array.filter(predicate).length > 0;
      │ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    2 │ 
  
  ℹ .some() matches that intent better and can stop as soon as it finds a match.
  
  ℹ This rule belongs to the nursery group, which means it is not yet stable and may change in the future. Visit https://biomejs.dev/linter/#nursery for more information.
  
  ℹ Unsafe fix: Use .some() instead.
  
    1   │ - array.filter(predicate).length·>·0;
      1 │ + array.some(predicate);
    2 2 │   
  

array.findIndex(predicate) !== -1;

code-block.js:1:1 lint/nursery/useArraySome  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ℹ This expression uses .findIndex() to test whether any array element matches.
  
  > 1 │ array.findIndex(predicate) !== -1;
      │ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    2 │ 
  
  ℹ .some() makes that intent clearer because it returns a boolean directly.
  
  ℹ This rule belongs to the nursery group, which means it is not yet stable and may change in the future. Visit https://biomejs.dev/linter/#nursery for more information.
  
  ℹ Unsafe fix: Use .some() instead.
  
    1   │ - array.findIndex(predicate)·!==·-1;
      1 │ + array.some(predicate);
    2 2 │   
  

if (array.find(predicate)) {}

code-block.js:1:5 lint/nursery/useArraySome ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ℹ This expression uses a .find()-style call as a boolean test.
  
  > 1 │ if (array.find(predicate)) {}
      │     ^^^^^^^^^^^^^^^^^^^^^
    2 │ 
  
  ℹ .some() makes that intent clearer because it returns a boolean directly.
  
  ℹ Use .some() instead.
  
  ℹ This rule belongs to the nursery group, which means it is not yet stable and may change in the future. Visit https://biomejs.dev/linter/#nursery for more information.
  

array.find(predicate) != null;

code-block.js:1:1 lint/nursery/useArraySome ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ℹ This expression uses .find() only to check whether an array element exists.
  
  > 1 │ array.find(predicate) != null;
      │ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    2 │ 
  
  ℹ .some() makes that intent clearer because it returns a boolean directly.
  
  ℹ Use .some() if you only need to know whether any element matches.
  
  ℹ This rule belongs to the nursery group, which means it is not yet stable and may change in the future. Visit https://biomejs.dev/linter/#nursery for more information.
  

array.findLastIndex(predicate) !== -1;

code-block.js:1:1 lint/nursery/useArraySome  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ℹ This expression uses .findLastIndex() to test whether any array element matches.
  
  > 1 │ array.findLastIndex(predicate) !== -1;
      │ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    2 │ 
  
  ℹ .some() makes that intent clearer because it returns a boolean directly.
  
  ℹ This rule belongs to the nursery group, which means it is not yet stable and may change in the future. Visit https://biomejs.dev/linter/#nursery for more information.
  
  ℹ Unsafe fix: Use .some() instead.
  
    1   │ - array.findLastIndex(predicate)·!==·-1;
      1 │ + array.some(predicate);
    2 2 │   
  

if (array.findLast(predicate)) {}

code-block.js:1:5 lint/nursery/useArraySome ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ℹ This expression uses a .find()-style call as a boolean test.
  
  > 1 │ if (array.findLast(predicate)) {}
      │     ^^^^^^^^^^^^^^^^^^^^^^^^^
    2 │ 
  
  ℹ .some() makes that intent clearer because it returns a boolean directly.
  
  ℹ Use .some() instead.
  
  ℹ This rule belongs to the nursery group, which means it is not yet stable and may change in the future. Visit https://biomejs.dev/linter/#nursery for more information.
  

Valid

array.some(predicate);

Related links

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