class ParallelInstaller::SpecInstallation

def dependencies_installed?(all_specs)

sure needed dependencies have been installed.
Checks installed dependencies against spec's dependencies to make 
def dependencies_installed?(all_specs)
  installed_specs = all_specs.select(&:installed?).map(&:name)
  dependencies(all_specs.map(&:name)).all? {|d| installed_specs.include? d.name }
end