Firestore rules - Unit testing Cloud Firestore

firestore.rules

service cloud.firestore {
  match /databases/{database}/documents {
    // GENERIC //

    function hasRoleForResource(targetResource, targetRoles) {
      return targetResource.data.role in targetRoles;
    }

    // USERS //

  	function isAuthenticated() {
      return request.auth != null;
    }

    function getUserResource(userId) {
      return get(/databases/$(database)/documents/users/$(userId));
    }

    // HOMESTEAD //

    function getHomesteadMemberPath(homesteadId) {
      return /databases/$(database)/documents/homesteads/$(homesteadId)/members/$(request.auth.uid);
    }

    function getHomesteadMembershipResource(homesteadId) {
      return get(getHomesteadMemberPath(homesteadId));
    }

    function hasHomesteadAccess(homesteadId) {
      return exists(getHomesteadMemberPath(homesteadId));
    }

    // ROUTES //

    match /{document=**} {
      allow read, write: if false;
    }

    match /homesteads/{homesteadId} {
      allow read: if hasHomesteadAccess(homesteadId);
      allow update: if hasRoleForResource(getHomesteadMembershipResource(homesteadId), ['owner']);
      allow create: if getUserResource(request.auth.uid).data.ownedHomestead == '';
    }

    match /users/{userId} {
      allow read, update: if request.auth.uid == userId;
    }
  }
}