swift - Firebase Firestore: Append/Remove items from document array

Question

I am trying to append/remove items from an array inside of a Firestore Document but every time the entire array is replaced instead of the new value being appended. I have tried both of the following:

batch.setData(["favorites": [user.uid]], forDocument: bookRef, options: SetOptions.merge())

batch.updateData(["favorites": [user.uid]], forDocument: bookRef)

I know that instead of an array I can use an object/dictionary but that would mean storing additional data that is irrelevant (such as the key), all I need is the ID's stored inside the array. Is this something that is currently possible in Firestore?

Answer 1

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