Fragments doesn't work in 0.17.0

[ulrikstrid]

Issue Labels

• has-reproduction
• feature
• docs
• blocking
• good first issue

I have a query like this:

query partnerCenterInvoiceLineItems($invoice_id: ID!) {
    partnerCenterInvoiceLineItems(invoice_id: $invoice_id) {
      customerId
      subscriptionId
      customerName
      ... on InvoiceLineItemsOffice {
        offerName
        subtotal
        quantity
        totalForCustomer
        subscriptionName
      }
      ... on InvoiceLineItemAzure {
        postTaxTotal
        postTaxEffectiveRate
        pretaxEffectiveRate
        pretaxCharges
        consumedQuantity
        listPrice
        serviceName
        subscriptionName
        unit
      }
      ... on InvoiceLineItemOneTime {
        subtotal
        quantity
        totalForCustomer
      }
    }
  }

When I use it with 0.17.0 I get errors in the console about heuristics matching and then I get no data. It works with previous versions so this is a regression.

[baransu]

I assume it's not a problem with reason-apollo itself but with underlying apollo-client, here is apollo documentation about it: https://www.apollographql.com/docs/react/advanced/fragments/#fragments-on-unions-and-interfaces

[ulrikstrid]

That was my first thought as well so I rolled back the apollo-client version but that didn't help so then I tried to rollback the version if reason-apollo and then it started working again. So something has changed in this repo that broke it.