Coverage increased (+0.2%) to 92.321% when pulling 188217c on imjm:input-enum-err into 96ed341 on vektah:master.

this rule is implemented in https://github.com/vektah/gqlparser/blob/master/validator/rules/values_of_correct_type.go#L71-L78 .
What is your use case?

so far, for the value is not in the enum list, it will return 422 error for the enum in argument, but 200 for the enum in the input object.

eg.

type Query {
  Todo(orderBy: OrderBy, input: TestInput): Todo
}

enum OrderBy {
  ASC
  DESC
}

input TestInput {
  inputOrderBy: OrderBy
}

for 422 Unprocessable Entity error

query {
  Todo(orderBy: AAA) { id }
}

for 200

query($input: TestInput) {
  Todo(input: $input) { id }
}

{
  "input": {
    "inputOrderBy": AAA
  }
}

both will give errors, but I think it should also return same http status code?

ah, make sense.

query A {
  enumInInput(input: {enum: "INVALID"})
}

query B($input: InputWithEnumValue) {
  enumInInput(input: $input)
}

I tried it by express-graphql, both returns 400 Bad Request and same response.

{"errors":[{"message":"Expected type EnumTest!, found \"INVALID\".","locations":[{"line":2,"column":29}]}]}

umm... This validation should execute in ValuesOfCorrectType rule.
https://github.com/graphql/graphql-js/blob/48ea2d3e8df5e4fbbdb5e0ce67c0a3c219b024f8/src/validation/rules/ValuesOfCorrectType.js#L118-L132
We wanna aligne to graphql-js implementations...