factory_girl

https://github.com/thoughtbot/factory_girl

Ruby

A library for setting up Ruby objects as test data.

Mail::Message#parse_message

2.1. General Description
  A message consists of header fields (collectively called "the header
  of the message") followed, optionally, by a body.  The header is a
  sequence of lines of characters with special syntax as defined in
  this standard. The body is simply a sequence of characters that
  follows the header and is separated from the header by an empty line
  (i.e., a line with nothing preceding the CRLF).

Source | Google | Stack overflow

Edit

git clone [email protected]:thoughtbot/factory_girl.git
cd factory_girl
open

Contribute

# Make a new branch

git checkout -b -your-name--update-docs-Mail--Message-parse_message-for-pr

# Commit to git

git add git commit -m "better docs for Mail::Message#parse_message"

# Open pull request

gem install hub # on a mac you can `brew install hub`

hub fork

git push <your name> -your-name--update-docs-Mail--Message-parse_message-for-pr

hub pull-request

# Celebrate!