noGlobalIsFinite

JavaScript (and super languages)

Summary

Rule available since: v1.0.0
Diagnostic Category: lint/suspicious/noGlobalIsFinite
This rule is recommended, which means is enabled by default.
This rule has an unsafe fix.
The default severity of this rule is error.

Description

Use Number.isFinite instead of global isFinite.

Number.isFinite() and isFinite() do not have the same behavior. When the argument to isFinite() is not a number, the value is first coerced to a number. Number.isFinite() does not perform this coercion. Therefore, it is a more reliable way to test whether a number is finite.

Examples

Invalid

1
isFinite(false); // true

code-block.js:1:1 lint/suspicious/noGlobalIsFinite  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ✖ isFinite is unsafe. It attempts a type coercion. Use Number.isFinite instead.
  
  > 1 │ isFinite(false); // true
      │ ^^^^^^^^
    2 │ 
  
  ℹ See the MDN documentation for more details.
  
  ℹ Unsafe fix: Use Number.isFinite instead.
  
    1   │ - isFinite(false);·//·true
      1 │ + Number.isFinite(false);·//·true
    2 2 │

Valid

1
Number.isFinite(false); // false

How to configure

1
{
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  "linter": {
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    "rules": {
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      "suspicious": {
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        "noGlobalIsFinite": "error"
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      }
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    }
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  }
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}