Mutations with payloads defined in the new post 1.8 DSL cannot handle lists of errors.

[stanishev]

Given the following mutation:

class BaseMutation < GraphQL::Schema::Mutation
end

module Mutations
  class UpdateSomething < BaseMutation
    description "Updates Something"
    payload_type Types::Output::User

    def resolve
      # something happens that causes multiple errors to be returned. 
      [GraphQL::ExecutionError.new("Error!")]
    end
  end
end

and the following output type defined using the new class based DSL (post 1.8):

module Types
  class BaseOutputObject < GraphQL::Schema::Object
    field_class Types::SeField
  end
end

module Types::Output
  class User < Types::BaseOutputObject
    graphql_name "User"

    field :email, String, null: false
    field :name, String, null: true
 end
end

and running the following query

mutation {  update_something() { email } }

Produces the following error:

{
  "errors": [
    {
      "message": "RuntimeError:         Failed to implement User.email, tried:\n\n        - `Types::Output::User#email`, which did not exist\n        - `Array#email`, which did not exist\n        - Looking up hash key `:email` or `\"email\"` on `[#<GraphQL::ExecutionError: Error!>]`, but it wasn't a Hash\n\n        To implement this field, define one of the methods above (and check for typos)\n",
      "type": "runtime"
    }
  ]
}

THIS IS THE ISSUE ^^^

It seems that the GraphQL error results are being treated by the gem as if they're a valid result.

However, using the old pre 1.8 DSL for the output type above:

module Types::Output
  User = GraphQL::ObjectType.define do
    name "User"

    field :email, !types.String
    field :name, types.String
  end
end

Produces the expected result:

{
  "data": null,
  "errors": [
    {
      "message": "Error!",
      "locations": [
        {
          "line": 2,
          "column": 3
        }
      ],
      "path": [
        "update_something"
      ]
    }
  ]
}

This seems to be related to what's happening in this line in the ProxiedResolve class in member/instrumentation.rb:

graphql-ruby/lib/graphql/schema/member/instrumentation.rb

Line 81 in 85ecd80

if ctx.skip == result || ctx.schema.lazy?(result) || result.nil? || result.is_a?(GraphQL::ExecutionError) || ctx.wrapped_object

It's not entirely clear to me what instrumentation is and why the above doesn't affect types and fields defined using the pre 1.8 DSL, but I'll link a PR with a fix that seems to address this.

[rmosolgo]

Duplicate of #1587, please see this comment a workaround:

#1587 (comment)

I don't plan to work on it anymore because it doesn't seem required by the spec. In fact, the spec seems to assume that a field with either return a value or raise an error; there's no mention of fields returning multiple errors.

However, if you want to implement it, I'll accept your PR!