Gem::Specification._load

# File tmp/rubies/ruby-3.0.5/lib/rubygems/specification.rb, line 1265
def self._load(str)
  Gem.load_yaml

  array = Marshal.load str

  spec = Gem::Specification.new
  spec.instance_variable_set :@specification_version, array[1]

  current_version = CURRENT_SPECIFICATION_VERSION

  field_count = if spec.specification_version > current_version
                  spec.instance_variable_set :@specification_version,
                                             current_version
                  MARSHAL_FIELDS[current_version]
                else
                  MARSHAL_FIELDS[spec.specification_version]
                end

  if array.size < field_count
    raise TypeError, "invalid Gem::Specification format #{array.inspect}"
  end

  # Cleanup any YAML::PrivateType. They only show up for an old bug
  # where nil => null, so just convert them to nil based on the type.

  array.map! {|e| e.kind_of?(YAML::PrivateType) ? nil : e }

  spec.instance_variable_set :@rubygems_version,          array[0]
  # spec version
  spec.instance_variable_set :@name,                      array[2]
  spec.instance_variable_set :@version,                   array[3]
  spec.date =                                             array[4]
  spec.instance_variable_set :@summary,                   array[5]
  spec.instance_variable_set :@required_ruby_version,     array[6]
  spec.instance_variable_set :@required_rubygems_version, array[7]
  spec.instance_variable_set :@original_platform,         array[8]
  spec.instance_variable_set :@dependencies,              array[9]
  # offset due to rubyforge_project removal
  spec.instance_variable_set :@email,                     array[11]
  spec.instance_variable_set :@authors,                   array[12]
  spec.instance_variable_set :@description,               array[13]
  spec.instance_variable_set :@homepage,                  array[14]
  spec.instance_variable_set :@has_rdoc,                  array[15]
  spec.instance_variable_set :@new_platform,              array[16]
  spec.instance_variable_set :@platform,                  array[16].to_s
  spec.instance_variable_set :@license,                   array[17]
  spec.instance_variable_set :@metadata,                  array[18]
  spec.instance_variable_set :@loaded,                    false
  spec.instance_variable_set :@activated,                 false

  spec
end