When using the "extend" keyword only, types aren't automatically imported

[antogyn]

Hey,

When using extend with a type, if it isn't anywhere in the schema without extend, input and return types used in its fields and the type itself aren't in the final schema unless explicitly imported.

This is a problem in federated services which sometimes only extend certain types.

# query.graphql
extend type Query {
  test: Test
}

type Test {
  ok: Boolean
}

# schema.graphql

# import Query from "query.graphql"

schema after importing schema.graphql (Test is absent):

extend type Query {
  test: Test!
}

Adding type Query { anyField: AnyType } anywhere produces a valid schema, but also drops the extend keyword

Other import methods:

# import Query.* from "query.graphql"

Same result

# import "query.graphql"
# import * from "query.graphql"

The Query type is not present at all (so in the exemple, it throws because it's an empty schema)