sideEffectsValidity

Enforces that the sideEffects property is valid.

✅ This rule is included in the package-json logical presets.

This rule checks that the sideEffects property is either a boolean or an array. If the value is an array, it should only consist of non-empty strings.

Examples

❌ Incorrect

{
  "sideEffects": "false"
}

✅ Correct

{
  "sideEffects": false
}

{
  "sideEffects": ["./dist/polyfills.js"]
}

When Not To Use It

If you don’t need compliance with npm’s sideEffects field specification, you can disable this rule. For example, if you use a different package manager that treats the field differently, this rule may not be correct for you.

Related Rules

• sideEffectsPresence - Enforces that the sideEffects property is present.

Equivalents in Other Linters

• ESLint: package-json/valid-sideEffects