validation doesn't honor default enum values

[andrew-kolesnikov]

Our particular spec has a mutation input containing channel: SimpleStringEnum! = WEB but to pass validation, router expects input to still have that field explicitly set.

Steps to reproduce the behavior:
{"input":{"channel":"MOBILE",...}}} passes validation
{"input":{...}}} doesn't with a cryptic error response: {“errors”:[{“message”:“invalid type for variable: ‘input’“,”locations”:[],“path”:null,“extensions”:{“type”:“ValidationInvalidTypeVariable”,“name”:“input”}}]}

[andrew-kolesnikov]

@Geal the problematic mutation uses fragments, and likely to be related to the work done for #1367

[Geal]

@andrew-kolesnikov could you show a reproducible test case?

With this schema:

enum Terminal {
    WEB,
    MOBILE
}
type Query{
    test: String
}
type Mutation {
    page(channel: Terminal! = WEB): String
}

and this query:

mutation GetPage($terminal: Terminal) {
    page(channel: $terminal)
}

right now it works, but if you could show me something with the same shape as your query that would help

[Geal]

ok I see the error with

mutation GetPage($terminal: Terminal!) {
    page(channel: $terminal)
}

[Geal]

hmm no, that fails because the operation itself actually needs a value. Can you show an example query?

[andrew-kolesnikov]

Using the following schema:

type Mutation{
    foo(input: FooInput!): FooResponse!
}

input FooInput {
  enumWithDefault: EnumWithDefault! = WEB
}

enum EnumWithDefault {
  WEB
  MOBILE
}

Request the following:

mutation foo($input: FooInput!) { 
    foo (input: $input) { 
    __typename
}}

{"input":{}}

Observe failed validation:

{
    "errors": [
        {
            "message": "invalid type for variable: 'input'",
            "locations": [],
            "path": null,
            "extensions": {
                "type": "ValidationInvalidTypeVariable",
                "name": "input"
            }
        }
    ]
}

Yet {"input":{"enumWithDefault":"MOBILE"}} seems to pass validation

[Geal]

alright, thanks!