class GraphQL::StaticValidation::VariableDefaultValuesAreCorrectlyTyped

def validate(context)
  context.visitor[GraphQL::Language::Nodes::VariableDefinition] << ->(node, parent) {
    if !node.default_value.nil?
      validate_default_value(node, context)
    end
  }
end

def validate_default_value(node, context)
  value = node.default_value
  if node.type.is_a?(GraphQL::Language::Nodes::NonNullType)
    context.errors << message("Non-null variable $#{node.name} can't have a default value", node, context: context)
  else
    type = context.schema.type_from_ast(node.type)
    if type.nil?
      # This is handled by another validator
    else
      begin
        valid = context.valid_literal?(value, type)
      rescue GraphQL::CoercionError => err
        error_message = err.message
      rescue GraphQL::LiteralValidationError
        # noop, we just want to stop any LiteralValidationError from propagating
      end
      if !valid
        error_message ||= "Default value for $#{node.name} doesn't match type #{type}"
        context.errors << message(error_message, node, context: context)
      end
    end
  end
end