opscode/chef — pull request #2581 by stevendanna (2014-12-09 13:36:04+00:00)
Title: Implement RFC 027 File Verification

This implements usable-suppliable file content verification per RFC
027. Users can supplie a block, string, or symbol to the `verify`
resource attribute. Blocks will be called, string will be executed as
shell commands (respecing the same options as not_if and only_if), and
symbols can be used to access built-in registered validations.