Response returns null on a non-nullable type

[theoks]

I am a bit baffled by the way the framework deals with non-nullable types.

For example I have a mutation like that:

mutation SignUp($email: String!, $password: String!) {
  signUp(email: $email, password: $password) {
    success
  }
}

with the respective GraphQL schema:

signUp(email: String!, password: String!): Result!

If I run this mutation through a client, in such a way that I get back an error (eg in this case I pass an empty email, which returns an error to the client):

{
	"data": {
		"signUp": null
	},
	"errors": [
		{
			"message": "Database error: email cannot be empty, message: email cannot be empty
			"path": [
				"signUp"
			]
		}
	]
}

The issue is that the signUp field is not nullable, however the server responds with null. In the beginning I believed it was a client issue, however after opening an issue in the apollo-ios github repo it seems that there must be something off with the way the library handles nullability.

The issue is, that because the server nulls a non-nullable result, the client cannot handle correctly the error. Instead of getting back the correct error, it detects a null response (which should not be null) and reports the null value as the error.

[vektah]

http://facebook.github.io/graphql/June2018/#sec-Errors-and-Non-Nullability

Looks like nulls should bubble up, and in this case data should be null.

[mikeifomin]

Have faced with the same issue after an update from 0.3 to 0.4.1. All my schema now lack of a non nullable =(

[vektah]

@mikeifomin that's a separate issue that should be fixed on master