Cannot update cache after mutation with errors

Intended outcome: I have a mutation which will fail when called with stale data. For example, if I had loaded the page with version 1 of a todo with an ID of 1, and while I was updating it a different user also updated the todo incrementing its version to 2, the server will respond with the following:

{
  "data": {
    "todo": {
      "id": 1,
      "version": 2,
      "description": "The updated todo description."
    }
  },
  "errors": [
    {
      "message": "Todo has been updated",
      "extensions": {
        "staleData": true
      }
    }
  ]
}

The idea here is that the server is responding with an error indicating that our mutation failed. In addition, it’s also providing the updated todo so the user can choose to cancel their edit or make it again. Since the server responds with the new version (and the rest of the latest todo information), the mutation will succeed the next time it’s called.

With this server response, the intent is to update the Todo:1 in the cache, and use the error details to trigger a “Are you sure you want to do this?” workflow.

Actual outcome: The update method of my mutation is never called because the response contains errors. None of the available errorPolicy options change this outcome, and I’ve been able to trace it down to this line of code.

How to reproduce the issue: https://codesandbox.io/s/apollo-client-error-template-1o8ix

In the above sandbox, nothing will be displayed in the UI and you’ll have to open the console. Look for the two INFO comments for instructions on switches that can be toggled. When errors exist in the response, we don’t see the My response is: console statement. When those errors don’t exist, we do.

I would expect to be able to update the cache in either case, but the Apollo client is preventing me from doing so when the server responds with errors.

Versions

  System:
    OS: macOS Mojave 10.14.6
  Binaries:
    Node: 10.16.0 - ~/.nvm/versions/node/v10.16.0/bin/node
    Yarn: 1.19.1 - /usr/local/bin/yarn
    npm: 6.9.0 - ~/.nvm/versions/node/v10.16.0/bin/npm
  Browsers:
    Firefox: 69.0
    Safari: 13.0.3
  npmPackages:
    apollo-cache: ^1.2.1 => 1.3.2 
    apollo-cache-inmemory: ^1.6.3 => 1.6.3 
    apollo-client: ^2.6.4 => 2.6.4 
    apollo-link-context: ^1.0.19 => 1.0.19 
    apollo-link-error: ^1.1.12 => 1.1.12 
    apollo-link-http: ^1.5.16 => 1.5.16 

[cunisia]

Sorry I had not seen @jcreighton answer to this other related issue. The provided code snippet demonstrates how to trigger the update method if the mutation’s result contains errors. errorPolicy option needs to be set to all.

Sorry for the inconvenience !

[mbergeronupgrade]

Leaving a comment in case someone encounters this in version 3+, the bug was present in 3.1.4 despite all the above recommendations but is working fine after updating to latest.