When Lodash isArrayLikeObject Rejects a NodeList

By default, the Lodash utility method _.isArrayLikeObject returns true when evaluated against a standard DOM NodeList because it is a non-null object featuring an integer-based length property. For _.isArrayLikeObject to reject a NodeList and return false, the instance must fail either Lodash's internal isObjectLike check or its isArrayLike check. Below are the precise technical conditions required for rejection.

How _.isArrayLikeObject Evaluates Values

Lodash defines _.isArrayLikeObject as:

function isArrayLikeObject(value) {
  return isObjectLike(value) && isArrayLike(value);
}

A standard NodeList normally satisfies both prerequisites:

• isObjectLike(value) ensures typeof value === 'object' and value !== null.
• isArrayLike(value) ensures value !== null, typeof value !== 'function', and isLength(value.length) is true.

Explicit Rejection Conditions

For a DOM NodeList to return false, one of the following explicit conditions must be met:

1. The length Property Fails isLength Validation

Lodash validates the length property using the internal isLength(value) predicate. A NodeList will be rejected if its .length property is tampered with or corrupted so that it violates any of the following constraints:

• Non-Integer Values: The .length property is modified to a floating-point number (e.g., nodeList.length = 2.5), failing the length % 1 === 0 integer check.
• Negative Values: The .length property is set to a negative number (length < 0).
• Values Exceeding Safe Limits: The .length property exceeds the maximum safe integer limit (nodeList.length > Number.MAX_SAFE_INTEGER, or 9007199254740991).
• Non-Numeric Types: The .length property is deleted or assigned a non-number type, such as a string, boolean, object, or undefined.
• Not a Number (NaN) or Infinity: The .length property is set to NaN, Infinity, or -Infinity.

2. The typeof Evaluation Returns 'function'

Lodash explicitly rejects any value where typeof value === 'function', even if that value possesses a valid .length property.

• In non-standard JavaScript runtimes, legacy browser engines, or polyfilled DOM environments where host objects or callable instances return typeof nodeList === 'function', _.isArrayLikeObject will immediately evaluate to false.
• Wrapping the NodeList inside a Proxy or custom callable structure that mimics a function causes the same rejection.

3. The Reference Is null or Fails Object Classification

The isObjectLike check requires the value to be both non-null and typed as an object:

• Null Reference: If the DOM query (such as document.querySelectorAll) returns null or the reference variable is cleared to null, it fails isObjectLike.
• Prototype Corruption / Coercion: If the NodeList instance is converted or coerced into a primitive (such as an empty string or symbol), it fails the typeof value === 'object' check.