demo of https://github.com/cfengine/core/pull/2031

gistfile1.txt

CFE policy:

body common control
{
      bundlesequence => { holder, test_datastate_mustache };
}

bundle common holder
{
  classes:
      "holderclass" expression => "any"; # will be global

  vars:
      "s" string => "Hello!";
      "d" data => parsejson('[4,5,6]');
      "list" slist => { "element1", "element2" };
}

bundle agent test_datastate_mustache
{
  files:
      "/tmp/myfile.txt"
      create => "true",
      edit_template => "$(this.promise_filename).mustache",
      template_method => "mustache";
}

CFE Mustache template:

{{%vars}}

{{%classes}}

Output:

{
  "sys": {
    "systime": "1416221536",
    "flavour": "ubuntu_14",
    "hardware_addresses": [
      "ff:ff:4e:8c:ff:f1",
      "ff:ff:27:00:ff:00"
    ],
    "fqhost": "flea",
    "uptime": "38787",
    "bindir": "/home/tzz/.cfagent/bin",
    "nova_version": "3.7.0a1.62bfb77",
    "arch": "x86_64",
    "ipv4": "192.168.1.48",
    "ipv4_2[eth0]": "192.168",
    "maildir": "/var/spool/mail",
    "logdir": "/home/tzz/.cfagent",
    "ipv4_1[lo]": "127",
    "ipv6_addresses": [
      "fe80::e2cb:4eff:fe8c:5f1",
      "fe80::800:27ff:fe00:0"
    ],
    "crontab": "/var/spool/cron/crontabs/tzz",
    "interface": "vboxnet0",
    "cf_monitord": "\"/home/tzz/.cfagent/bin/cf-monitord\"",
    "key_digest": "SHA=a79c242b4e6e0e5678452d8fc9ffffff8ae3a311af2dcf3e0d5ed145efb0a554",
    "local_libdir": "lib/3.7",
    "interface_flags[vboxnet0]": "up broadcast running multicast",
    "cpus": "8",
    "cf_version_minor": "7",
    "ipv4[vboxnet0]": "192.168.33.1",
    "class": "linux",
    "ip_addresses": [
      "127.0.0.1",
      "192.168.1.48",
      "192.168.33.1"
    ],
    "cf_serverd": "\"/home/tzz/.cfagent/bin/cf-serverd\"",
    "date": "Mon Nov 17 05:52:16 2014",
    "interface_flags[lo]": "up loopback running",
    "ipv4_1[vboxnet0]": "192",
    "interfaces": [
      "eth0",
      "vboxnet0"
    ],
    "cf_runagent": "\"/home/tzz/.cfagent/bin/cf-runagent\"",
    "flavor": "ubuntu_14",
    "ostype": "linux_x86_64",
    "uqhost": "flea",
    "os": "linux",
    "interface_flags[eth0]": "up broadcast running multicast",
    "enterprise_version": "3.7.0a1.62bfb77",
    "piddir": "/home/tzz/.cfagent",
    "failsafe_policy_path": "/home/tzz/.cfagent/inputs/failsafe.cf",
    "exports": "/etc/exports",
    "ipv4[eth0]": "192.168.1.48",
    "release": "3.11.0-15-generic",
    "cf_version": "3.7.0a1.c639fe1",
    "domain": "",
    "ipv4_1[eth0]": "192",
    "fstab": "/etc/fstab",
    "hardware_flags": [
      "up loopback running",
      "up broadcast running multicast",
      "up broadcast running multicast"
    ],
    "ipv4_3[vboxnet0]": "192.168.33",
    "cf_promises": "\"/home/tzz/.cfagent/bin/cf-promises\"",
    "cf_version_patch": "0",
    "ipv4_2[vboxnet0]": "192.168",
    "version": "#25-Ubuntu SMP Thu Jan 30 17:22:01 UTC 2014",
    "hardware_mac[eth0]": "ff:ff:ff:ff:ff:ff",
    "cf_version_major": "3",
    "doc_root": "/var/www",
    "cf_key": "\"/home/tzz/.cfagent/bin/cf-key\"",
    "ipv4_3[lo]": "127.0.0",
    "masterdir": "/home/tzz/.cfagent/masterfiles",
    "cf_twin": "\"/home/tzz/.cfagent/bin/cf-twin\"",
    "cf_execd": "\"/home/tzz/.cfagent/bin/cf-execd\"",
    "ipv4_3[eth0]": "192.168.1",
    "cf_upgrade": "\"/home/tzz/.cfagent/bin/cf-upgrade\"",
    "ipv4_2[lo]": "127.0",
    "update_policy_path": "/home/tzz/.cfagent/inputs/update.cf",
    "hardware_mac[vboxnet0]": "ff:ff:ff:00:00:00",
    "cdate": "Mon_Nov_17_05_52_16_2014",
    "libdir": "/home/tzz/.cfagent/inputs/lib/3.7",
    "workdir": "/home/tzz/.cfagent",
    "long_arch": "linux_x86_64_3_11_0_15_generic__25_Ubuntu_SMP_Thu_Jan_30_17_22_01_UTC_2014",
    "ipv4[lo]": "127.0.0.1",
    "host": "flea",
    "inputdir": "/home/tzz/.cfagent/inputs",
    "cf_agent": "\"/home/tzz/.cfagent/bin/cf-agent\"",
    "resolv": "/etc/resolv.conf",
    "sysday": "16391"
  },
  "holder": {
    "list": [
      "element1",
      "element2"
    ],
    "s": "Hello!",
    "d": [
      4,
      5,
      6
    ]
  },
  "const": {
    "t": "\t",
    "n": "\n",
    "dollar": "$",
    "dirsep": "/",
    "endl": "\n",
    "r": "\r"
  },
  "control_common": {
    "bundlesequence": [
      "holder",
      "test_datastate_mustache"
    ]
  }
}

{
  "flea_local": true,
  "agent": true,
  "Lcycle_1": true,
  "192_168_1_48": true,
  "Hr5": true,
  "x86_64": true,
  "GMT_Min52": true,
  "ubuntu_14": true,
  "mac_ff_ff_ff_ff_ff_ff": true,
  "GMT_Yr2014": true,
  "ipv4_192_168": true,
  "nova": true,
  "linux_x86_64": true,
  "enterprise_3_7_0a1_62bfb77": true,
  "GMT_Q4": true,
  "ubuntu": true,
  "Min50_55": true,
  "nova_edition": true,
  "GMT_Hr10_Q4": true,
  "enterprise_3_7": true,
  "enterprise_edition": true,
  "GMT_Lcycle_1": true,
  "Q4": true,
  "Hr05": true,
  "inform_mode": true,
  "localhost": true,
  "Monday": true,
  "linux_x86_64_3_11_0_15_generic": true,
  "linux_x86_64_3_11_0_15_generic__25_Ubuntu_SMP_Thu_Jan_30_17_22_01_UTC_2014": true,
  "PK_SHA_edited": true,
  "debian_jessie": true,
  "GMT_Monday": true,
  "Min52": true,
  "November": true,
  "enterprise": true,
  "ipv4_192_168_33_1": true,
  "compiled_on_linux_gnu": true,
  "192_168_33_1": true,
  "ipv6_fe80__800_27ff_fe00_0": true,
  "8_cpus": true,
  "cfengine_3_7_0a1_c639fe1": true,
  "linux": true,
  "GMT_Hr10": true,
  "nova_3_7_0a1_62bfb77": true,
  "ipv6_fe80__e2cb_4eff_fe8c_5f1": true,
  "64_bit": true,
  "net_iface_vboxnet0": true,
  "cfengine_3_7_0a1": true,
  "nova_3": true,
  "Night": true,
  "ipv4_192": true,
  "ubuntu_14_4": true,
  "linux_3_11_0_15_generic": true,
  "Hr05_Q4": true,
  "fe80__e2cb_4eff_fe8c_5f1": true,
  "cfengine": true,
  "cfengine_3": true,
  "ipv4_127_0": true,
  "nova_3_7_0a1": true,
  "mac_ff_ff_ff_00_00_00": true,
  "Day17": true,
  "GMT_Morning": true,
  "ipv4_127": true,
  "127_0_0_1": true,
  "Yr2014": true,
  "nova_3_7": true,
  "ipv4_192_168_1_48": true,
  "enterprise_3": true,
  "holderclass": true,
  "GMT_November": true,
  "cfengine_3_7": true,
  "enterprise_3_7_0a1": true,
  "debian": true,
  "flea": true,
  "net_iface_eth0": true,
  "any": true,
  "cfdc_utilities_run_once:_special_script___activation_id_": true,
  "ipv4_192_168_1": true,
  "fe80__800_27ff_fe00_0": true,
  "ipv4_192_168_33": true,
  "net_iface_lo": true,
  "ipv4_127_0_0_1": true,
  "ipv4_127_0_0": true,
  "GMT_Day17": true,
  "GMT_Min50_55": true
}

This doesn't seem to work in 3.6.5, does it work on 3.7 only?