Module: GraphQL::Execution::Typecast

Defined in:
lib/graphql/execution/typecast.rb

Overview

GraphQL object ‘type` can be cast to `other_type` when:

  • ‘type == other_type`

  • ‘type` is a union and it resolves `value` to `other_type`

  • ‘other_type` is a union and `type` is a member

  • ‘type` is an interface and it resolves `value` to `other_type`

  • ‘other_type` is an interface and `type` implements that interface

Class Method Summary collapse

Class Method Details

.compatible?(value, current_type, potential_type, query_ctx) ⇒ Boolean

While ‘value` is exposed by GraphQL as an instance of `current_type`, should it also be treated as an instance of `potential_type`?

This is used for checking whether fragments apply to an object.

Returns:

  • (Boolean) —

    Can ‘value` be evaluated as a `potential_type`?



16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
 
# File 'lib/graphql/execution/typecast.rb', line 16

def self.compatible?(value, current_type, potential_type, query_ctx)
  if potential_type == current_type
    true
  elsif current_type.kind.union?
    current_type.resolve_type(value, query_ctx) == potential_type
  elsif potential_type.kind.union?
    potential_type.include?(current_type)
  elsif current_type.kind.interface?
    current_type.resolve_type(value, query_ctx) == potential_type
  elsif potential_type.kind.interface?
    current_type.interfaces.include?(potential_type)
  else
    false
  end
end