Error types (instanceof) are lost if thrown from resolver

apollo-server-express@2.6.3

If I throw an AuthenticationError from a resolver, I cannot detect this from the formatError handler. For example:

// somewhere in a resolver...
import { AuthenticationError } from 'apollo-server-express'
const resolve = (_, args, context) => {
  throw new AuthenticationError('test')
}

// in formatError handler
const formatError = (error) => {
  console.log(error instanceof AuthenticationError) // returns false
  return error
}

HOWEVER, if the error is SyntaxError or ValidationError produced by GraphQL automatically due to a malformatted graphql request, then the instanceof check works.

A quick working sample: https://codesandbox.io/s/apollo-server-ft3ul?fontsize=14

[bnaoki]

Have you tried checking error.originalError?

[kabachook]

Same for me, it just returns GraphQLError for everything. My version is 2.6.4. But I believe this bug also works since versions ^2.4.8.