capistrano/capistrano — pull request #427 by nlenepveu (2013-04-03 16:19:41+00:00)
Title: Fix "undefined method shellescape for nil:NilClass (NoMethodError)"

If `deploy:assets:precompile` is executed while no servers match and `current_release` is not yet evaluated, the task try to call `shellescape` on nil.

This prevents this case by just silent error during the build of the command line.