Support custom fields on a mocked GraphQL response

Scope

Improves an existing behavior

Compatibility

• This is a breaking change

Feature description

I’m using msw for mocking grapghql api calls in react testing library tests of my application. I have a requirement to pass following object as the response context, to simulate an error response behavior

{
            "networkError": {
                "statusCode": "404"
            },
            "message": "Not Found",
            "metadata": {
                "errorCode": "Repository Not Accessible",
                "additionalData": "http://github.com/testUser/repo-to-be-deleted"
            }
        }

However when setting the response context it only allows me to set data, headers, delay, extensions and some other predefined fields for the context. I need to be able to set custom values, for an example as per the above object I need to set metadata and message fields

[kettanaito]

Released: v0.42.1 🎉

This has been released in v0.42.1!

• 📄 Release notes
• 📦 npm package

Make sure to always update to the latest version (npm i msw@latest) to get the newest features and bug fixes.

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[Poivey]

Ok I will start working on it, I will create a pull request as soon as I have the first implementation to get your feedback !