requireResolversForArgs incorrectly labelled as missing with subscription args

[Darkbladecr]

Describe the bug
When arguments are added to the subscription type on the graphQL schema the requireResolversForArgs is incorrectly erroring.

type Subscription {
  numberIncremented(id: Int): Int
}

Resolver missing for "Subscription.numberIncremented".

To Reproduce
Example forked from official Apollo-server example:
https://codesandbox.io/s/pensive-joliot-brxcj?file=/index.js

Expected behavior
If arguments taken off the subscription type in the schema, everything works fine.

• OS:
• @graphql-tools/...: 7.1.5

[Urigo]

Hi @Darkbladecr and thank you for the report

Sorry but I'm not adding a lot here but just labeling it according to our new Contribution Guide and issue flow.

It seems already got into stage 1 thanks to your reproduction! Thank you for that!

Now in order to advance to stage 2 we'll need a failing test, would be great if someone could help progress the issues through the stages.

Thank you and sorry that this comment is not a complete solution (yet).

[goldenice]

I don't really have the knowledge to figure out an in-depth solution or even write a unit test on this project, but it seems that in the expectResolver function in assertResolversPresent.ts, the code will check whether field.resolve is defined and error if it isn't. For subscriptions it appears this resolve is indeed undefined, instead the field has a field.subscribe property.

Not sure whether the check in expectResolver should be expanded to include field.subscribe, or the field.resolve should be implemented at that point for subscriptions.

Hope this helps.