#######################################################################
###
### Filesystem checks
###
<% if $nhc::check_fs_mount { -%>
<% $nhc::check_fs_mount.each |$fs_struct| { -%>
  <%
     $function = $fs_struct['fs_mode'] ? {
       'ro'    => 'check_fs_mount_ro',
       'rw'    => 'check_fs_mount_rw',
       default => 'check_fs_mount'
     }
     $nonfatal = $fs_struct['nonfatal'] ? {
       true    => '-0',
       default => undef
     }
     $remount  = $fs_struct['remount'] ? {
       true    => '-r',
       default => undef
     }
     $options  = $fs_struct['options'] ? {
       true    => "-o ${fs_struct['options']}",
       default => undef
     }
     $mount_opts  = $fs_struct['mount_opts'] ? {
       true    => "-O ${fs_struct['mount_opts']}",
       default => undef
     }
     $notfound_cmd  = $fs_struct['notfound_cmd'] ? {
       true    => "-e ${fs_struct['notfound_cmd']}",
       default => undef
     }
     $found_cmd  = $fs_struct['found_cmd'] ? {
       true    => "-E ${fs_struct['found_cmd']}",
       default => undef
     }
     $fs_name  = "-f ${fs_struct['fs_name']}"
     $fs_type  = $fs_struct['fs_type'] ? {
       true    => "-t ${fs_struct['fs_type']}",
       default => undef
     }
     $fs_source  = $fs_struct['fs_source'] ? {
       true    => "-s ${fs_struct['fs_source']}",
       default => undef
     }
     $formats = {
       String => {
         "format"         => "% s",
         "string_formats" => {
           String => "%s"
         }
       },
       String[0,0] => {
         "format"         => "% p",
         "string_formats" => {
           String => "%s"
         }
       },
       Array => {
         format         => '% a',
         separator      => '',
         string_formats => {
           String => '%t',
         }
       },
       Undef => {
         "format"         => "% s",
         "string_formats" => {
           String => "%s"
         }
       }
     }
     $filtered_fs = [
       $function,
       $nonfatal,
       $remount,
       $fs_source,
       $fs_type,
       $options,
       $mount_opts,
       $notfound_cmd,
       $found_cmd,
       $fs_name,
     ].filter |$item| { $item =~ NotUndef }
     $final_fs = String($filtered_fs,$formats)
  -%>
   * || <%= $final_fs %>
<% } -%>
<% } -%>

puppet agent -t results(note the square brackets, shouldn't be there):
     * || ['check_fs_mount_rw', '-f /']
     * || ['check_fs_mount_rw', '-f /tmp']
     * || ['check_fs_mount_rw', '-f /localscratch']
     * || ['check_fs_mount', '-f /opt/software']
     * || ['check_fs_mount_rw', '-f /home']
     * || ['check_fs_mount_rw', '-f /project']
     * || ['check_fs_mount_rw', '-f /scratch']
     * || ['check_fs_mount_rw', '-f /cvmfs']

puppet apply results:
     * || check_fs_mount_rw -f /
     * || check_fs_mount_rw -f /tmp
     * || check_fs_mount_rw -f /localscratch
     * || check_fs_mount -f /opt/software
     * || check_fs_mount_rw -f /home
     * || check_fs_mount_rw -f /project
     * || check_fs_mount_rw -f /scratch
     * || check_fs_mount_rw -f /cvmfs