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javascriptfirebasereact-nativegoogle-cloud-firestorereact-native-firebase

firestore: user Array.includes with a DocumentReference

I'm trying check if an array with DocumetReferences contains a specific ref.

That's my attempt:

const likedWorkouts = user.collection('additional').doc('liked');
const snapshot = await likedWorkouts.get();
const exists = snapshot.exists;
hasLiked = snapshot.data()?.liked?.includes(workout); // This part (workout is a DocumentReference)
Solution

  • A DocumentReference is an object and you cannot compare them directly. You can use the isEqual() method to compare the refs:

    hasLiked = !!snapshot.data()?.liked?.find((likeRef) => likeRef.isEqual(workout));

// Alternatively, you can compare the paths
// likeRef.path === workout.path

    The DocumentReference in the new Modular SDK doesn't not have isEqual() method but instead there is a top level function refEqual(). It can be used as follows:

    import { refEqual } from "firebase/firestore";

hasLiked = !!snapshot.data()?.liked?.find((likeRef) => refEqual(likeRef, workout));

    Checkout MDN for more information on objects.