rspec/rspec-core — pull request #728 by charliemaffitt (2012-11-13 22:26:48+00:00)
Title: Defines shellescape method

Method allows newer versions of Ruby to use string.shellescape while not breaking in 1.8.6.

Attempting to solve the issue introduced in this comment:
https://github.com/rspec/rspec-core/pull/721#issuecomment-10054185