Module: GraphQL::Execution::Typecast

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

Overview

GraphQL object ‘current_type` can be cast to `potential_type` when:

  • ‘current_type == potential_type`

  • ‘current_type` is a union and it contains `potential_type`

  • ‘potential_type` is a union and it contains `current_type`

  • ‘current_type` is an interface and `potential_type` implements it

  • ‘potential_type` is an interface and `current_type` implements it

Class Method Summary collapse

Class Method Details

.compatible?(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.

Parameters:

Returns:

  • (Boolean) —

    true if ‘value` be evaluated as a `potential_type`



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# File 'lib/graphql/execution/typecast.rb', line 20

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