new-for-builtins.md

Enforce the use of new for all builtins, except String, Number, Boolean, Symbol and BigInt

✅ This rule is part of the recommended config.

🔧 This rule is auto-fixable.

They work the same, but new should be preferred for consistency with other constructors.

Enforces the use of new for following builtins:

• Object
• Array
• ArrayBuffer
• BigInt64Array
• BigUint64Array
• DataView
• Date
• Error
• Float32Array
• Float64Array
• Function
• Int8Array
• Int16Array
• Int32Array
• Map
• WeakMap
• Set
• WeakSet
• Promise
• RegExp
• Uint8Array
• Uint16Array
• Uint32Array
• Uint8ClampedArray
• SharedArrayBuffer
• Proxy
• WeakRef
• FinalizationRegistry

Disallows the use of new for following builtins.

• String
• Number
• Boolean
• Symbol
• BigInt

These should not use new as that would create object wrappers for the primitive values, which is not what you want. However, without new they can be useful for coercing a value to that type.

This rule is fixable, except new String(), new Number(), and new Boolean(), they return wrapped object.

Fail

const list = Array(10);

const now = Date();

const map = Map([
	['foo', 'bar']
]);

Pass

const list = new Array(10);

const now = new Date();

const map = new Map([
	['foo', 'bar']
]);