ObjectType, Input, Enum, and Interface Definitions should not be allowed with zero fields.

[ssko1]

Current

type Query {}
type Foo {}
input Bar {}
interface Qux {}
enum Quux {}

fails the following test

func TestMustHaveOneField(t *testing.T) {
	_, err := graphql.ParseSchema("type Query {} input Bar {} interface Qux {} enum Quux {}", nil)
	if err == nil {
		t.Fatal("types, inputs, interfaces and enums must have at least one field")
	}
}

Expected

Types, inputs, interfaces, and enums should be validated to ensure that there is at least one field.

Relevant specification links
ObjectTypeDefinition validation: https://spec.graphql.org/draft/#sel-HAHZhCFBABABuBq9O
InterfaceTypeDefinition validation: https://spec.graphql.org/draft/#sel-HAHbnBFBABABxB4a
EnumTypeDefinition validation: https://spec.graphql.org/draft/#sel-HAHfVFBABAB4B_6J
InputObjectTypeDefinition validation: https://spec.graphql.org/draft/#sel-HAHhBXDBABAB6BpkU

Environment

• tested against the master branch

I'd be more than happy to contribute a fix.

[ssko1]

There is a PR open for this issue: #127, but it hasn't been touched in 2 years.

[pavelnikolov]

@ssko1 feel free to take it and resolve the conflicts