Sparse Updates Serializing Missing Values Incorrectly #239

Reproduction Steps

Assuming at least 1 location is present in the environment under test

client = Square::Client.new(token: ENV.fetch('SQUARE_ACCESS_TOKEN'), base_url: Square::Environment::SANDBOX)

location_id = client.locations.list.locations.first.id
order = client.orders.create(idempotency_key: SecureRandom.uuid, order: { location_id: }).order

# this SHOULD do nothing.

client.orders.update(order_id: order.id,
                     idempotency_key: SecureRandom.uuid,
                     order: {})

Expectation

No-op, no exception raised

Observation

Exception gets raised, because location_id is serialized as an empty hash

Square::Errors::ClientError: {"errors": [{"code": "EXPECTED_STRING","detail": "Expected a string value (line 1, character 25)","field": "order.location_id","category": "INVALID_REQUEST_ERROR"}]} (Square::Errors::ClientError)

Notes

This applies to all attributes that are not passed in, not just location_id - e.g. line item quantities is the other attribute tripping our system.