Remove default value from helpers.arrayElement()

[ST-DDT]

faker/src/random.ts

Lines 106 to 108 in 4eef328

	arrayElement<T = string>(
	array: ReadonlyArray<T> = ['a', 'b', 'c'] as unknown as ReadonlyArray<T>
	): T {

This causes issues with missing data, that then gets magically replaced with these defaults, which results in unexpected behavior.
This change could be considered breaking, but IMO calling that method without an array to choose from is a bug itself.
Thus why I consider this a bug, that needs fixing more than retaining backwards compatibility.

We observed this method misbehaving in our tests before.

Alternatives considered

Create a new method and deprecate the old one.

Additional Information

Related to #219

[xDivisionByZerox]

If calling the method with an empty array is considered a bug, what would be the correct behavior for empty arrays?

[Shinigami92]

IMO we should "just" remove the = ['a', 'b', 'c'] as unknown as ReadonlyArray<T> part, so that a given argument is required.
But is it really a bug if calling it with an empty array? Cause this would be already a bug now 👀
I would assume that it would throw an error or just return undefined 🤔

[xDivisionByZerox]

If it could return undefined you must extend the method signature with undefined as return value. This can be very exhausting for end-users (because undefined check). So I would say throwing an error would be the way to go.

[xDivisionByZerox]

Can you assign me either way?

[xDivisionByZerox]

Fixed by #2045.