def delete(filename)
      within_source_root do
        FileUtils.mkdir_p File.dirname(filename)
        FileUtils.touch   filename
      end
      
      generate { expect(File).not_to exist(filename) }
    end
def delete(filename)
      within_source_root do
        FileUtils.mkdir_p File.dirname(filename)
        FileUtils.touch   filename
      end
      
      generate { expect(File).not_to exist(filename) }
    end
Makes sure that the generator deletes the named file. This is done by first ensuring that the
 file exists in the first place, and then ensuring that it does not exist after the generator
 completes its run.

 Example:
   expect(subject).to delete("path/to/file")