Stack level too deep (SystemStackError) #1176

/Users/bogdan/.rbenv/versions/2.1.10/lib/ruby/gems/2.1.0/gems/yard-0.9.14/lib/yard/parser/ruby/ast_node.rb:212: stack level too deep (SystemStackError)

~/Desktop » gem fetch mail       
Fetching: mail-2.7.0.gem (100%)
Downloaded mail-2.7.0
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~/Desktop » gem unpack mail-2.7.0.gem 
Unpacked gem: '/Users/bogdan/Desktop/mail-2.7.0'
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~/Desktop » cd mail-2.7.0 
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~/Desktop/mail-2.7.0 » yard --debug
[debug]: Parsing ["{lib,app}/**/*.rb", "ext/**/*.{c,cc,cxx,cpp}"] with `ruby` parser
[debug]: Parsing lib/mail.rb
[debug]: Parsing lib/mail/body.rb
[debug]: Parsing lib/mail/mail.rb
[debug]: Parsing lib/mail/part.rb
[debug]: Parsing lib/mail/field.rb
[debug]: Parsing lib/mail/fields.rb
[debug]: Parsing lib/mail/header.rb
[debug]: Parsing lib/mail/message.rb
[debug]: Parsing lib/mail/network.rb
[debug]: Parsing lib/mail/parsers.rb
[debug]: Parsing lib/mail/version.rb
[debug]: Parsing lib/mail/elements.rb
[debug]: Parsing lib/mail/envelope.rb
[debug]: Parsing lib/mail/constants.rb
[debug]: Parsing lib/mail/encodings.rb
[debug]: Parsing lib/mail/multibyte.rb
[debug]: Parsing lib/mail/utilities.rb
[debug]: Parsing lib/mail/field_list.rb
[debug]: Parsing lib/mail/parts_list.rb
[debug]: Parsing lib/mail/parser_tools.rb
[debug]: Parsing lib/mail/configuration.rb
[debug]: Parsing lib/mail/encodings/7bit.rb
[debug]: Parsing lib/mail/encodings/8bit.rb
[debug]: Parsing lib/mail/fields/cc_field.rb
[debug]: Parsing lib/mail/fields/to_field.rb
[debug]: Parsing lib/mail/multibyte/chars.rb
[debug]: Parsing lib/mail/multibyte/utils.rb
[debug]: Parsing lib/mail/attachments_list.rb
[debug]: Parsing lib/mail/elements/address.rb
[debug]: Parsing lib/mail/encodings/base64.rb
[debug]: Parsing lib/mail/encodings/binary.rb
[debug]: Parsing lib/mail/fields/bcc_field.rb
[debug]: Parsing lib/mail/indifferent_hash.rb
[debug]: Parsing lib/mail/fields/date_field.rb
[debug]: Parsing lib/mail/fields/from_field.rb
[debug]: Parsing lib/mail/multibyte/unicode.rb
[warn]: in YARD::Handlers::Ruby::AttributeHandler: Undocumentable ATTRIBUTES
	in file 'lib/mail/multibyte/unicode.rb':333:

	333: attr_writer(*ATTRIBUTES)

[debug]: Parsing lib/mail/encodings/identity.rb
[debug]: Parsing lib/mail/fields/sender_field.rb
[debug]: Parsing lib/mail/core_extensions/smtp.rb
[debug]: Parsing lib/mail/elements/phrase_list.rb
[debug]: Parsing lib/mail/fields/subject_field.rb
[debug]: Parsing lib/mail/check_delivery_params.rb
[debug]: Parsing lib/mail/elements/address_list.rb
[debug]: Parsing lib/mail/fields/comments_field.rb
[debug]: Parsing lib/mail/fields/keywords_field.rb
[debug]: Parsing lib/mail/fields/optional_field.rb
[debug]: Parsing lib/mail/fields/received_field.rb
[debug]: Parsing lib/mail/fields/reply_to_field.rb
[debug]: Parsing lib/mail/core_extensions/string.rb
[debug]: Parsing lib/mail/encodings/unix_to_unix.rb
[debug]: Parsing lib/mail/fields/resent_cc_field.rb
[debug]: Parsing lib/mail/fields/resent_to_field.rb
[debug]: Parsing lib/mail/matchers/has_sent_mail.rb
[debug]: Parsing lib/mail/fields/content_id_field.rb
[debug]: Parsing lib/mail/fields/message_id_field.rb
[debug]: Parsing lib/mail/fields/references_field.rb
[debug]: Parsing lib/mail/fields/resent_bcc_field.rb
[debug]: Parsing lib/mail/fields/structured_field.rb
[debug]: Parsing lib/mail/parsers/received_parser.rb
[debug]: Parsing lib/mail/fields/in_reply_to_field.rb
[debug]: Parsing lib/mail/fields/resent_date_field.rb
[debug]: Parsing lib/mail/fields/resent_from_field.rb
[debug]: Parsing lib/mail/fields/return_path_field.rb
[debug]: Parsing lib/mail/parsers/date_time_parser.rb
[debug]: Parsing lib/mail/elements/received_element.rb
[debug]: Parsing lib/mail/fields/common/common_date.rb
[debug]: Parsing lib/mail/fields/content_type_field.rb
[debug]: Parsing lib/mail/fields/mime_version_field.rb
[debug]: Parsing lib/mail/fields/unstructured_field.rb
[debug]: Parsing lib/mail/version_specific/ruby_1_8.rb
[debug]: Parsing lib/mail/version_specific/ruby_1_9.rb
[debug]: Parsing lib/mail/elements/date_time_element.rb
[debug]: Parsing lib/mail/encodings/quoted_printable.rb
[debug]: Parsing lib/mail/fields/common/common_field.rb
[debug]: Parsing lib/mail/fields/resent_sender_field.rb
[debug]: Parsing lib/mail/parsers/message_ids_parser.rb
[debug]: Parsing lib/mail/encodings/transfer_encoding.rb
[debug]: Parsing lib/mail/parsers/content_type_parser.rb
[debug]: Parsing lib/mail/parsers/mime_version_parser.rb
[debug]: Parsing lib/mail/parsers/phrase_lists_parser.rb
[debug]: Parsing lib/mail/elements/message_ids_element.rb
[debug]: Parsing lib/mail/fields/common/common_address.rb
[debug]: Parsing lib/mail/fields/common/parameter_hash.rb
[debug]: Parsing lib/mail/matchers/attachment_matchers.rb
[debug]: Parsing lib/mail/parsers/address_lists_parser.rb
/Users/bogdan/.rbenv/versions/2.1.10/lib/ruby/gems/2.1.0/gems/yard-0.9.14/lib/yard/parser/ruby/ast_node.rb:212: stack level too deep (SystemStackError)

## Environment details:

* OS: macOS 10.13.5 (17F77)
* Ruby version (`ruby -v`): ruby 2.1.10p492 (2016-04-01 revision 54464) [x86_64-darwin17.0]
* YARD version (`yard -v`): yard 0.9.14

I have read the [Contributing Guide][contrib].

[contrib]: https://github.com/lsegal/yard/blob/master/CONTRIBUTING.md