file.serialize JSON w/merge_if_exists fails if top-level is not a dict

[The-Loeki]

Description of Issue/Question

file.serialize has the merge_if_exists option.
When serializing to JSON, it apparently assumes the top level to be a dict.
While this is of course extremely common, it's not always true, and when it's not, the serializer crashes.

Steps to Reproduce Issue

SLS:

my-json-list:
  file.serialize:
    - name: /tmp/list.json
    - formatter: json
    - merge_if_exists: True
    - dataset:
        - tea
        - pot

# cat /tmp/list.json
[  "tea", "kettle" ]

          ID: my-json-list
    Function: file.serialize
        Name: /tmp/list.json
      Result: False
     Comment: An exception occurred in this state: Traceback (most recent call last):
                File "/usr/lib/python2.7/dist-packages/salt/state.py", line 1746, in call
                  **cdata['kwargs'])
                File "/usr/lib/python2.7/dist-packages/salt/loader.py", line 1704, in wrapper
                  return f(*args, **kwargs)
                File "/usr/lib/python2.7/dist-packages/salt/states/file.py", line 5144, in serialize
                  merged_data = salt.utils.dictupdate.merge_recurse(existing_data, dataset)
                File "/usr/lib/python2.7/dist-packages/salt/utils/dictupdate.py", line 82, in merge_recurse
                  return update(copied, obj_b, merge_lists=merge_lists)
                File "/usr/lib/python2.7/dist-packages/salt/utils/dictupdate.py", line 35, in update
                  raise TypeError('Cannot update using non-dict types in dictupdate.update()')
              TypeError: Cannot update using non-dict types in dictupdate.update()
     Started: 11:32:11.537613
    Duration: 3.339 ms
     Changes:   

Versions Report

Salt Version:
           Salt: 2016.11.4
 
Dependency Versions:
           cffi: Not Installed
       cherrypy: Not Installed
       dateutil: 2.4.2
      docker-py: Not Installed
          gitdb: Not Installed
      gitpython: Not Installed
          ioflo: Not Installed
         Jinja2: 2.8
        libgit2: Not Installed
        libnacl: Not Installed
       M2Crypto: Not Installed
           Mako: 1.0.3
   msgpack-pure: Not Installed
 msgpack-python: 0.4.6
   mysql-python: Not Installed
      pycparser: Not Installed
       pycrypto: 2.6.1
   pycryptodome: Not Installed
         pygit2: Not Installed
         Python: 2.7.12 (default, Nov 19 2016, 06:48:10)
   python-gnupg: Not Installed
         PyYAML: 3.11
          PyZMQ: 15.2.0
           RAET: Not Installed
          smmap: Not Installed
        timelib: Not Installed
        Tornado: 4.2.1
            ZMQ: 4.1.4
 
System Versions:
           dist: Ubuntu 16.04 xenial
        machine: x86_64
        release: 4.10.0-20-generic
         system: Linux
        version: Ubuntu 16.04 xenial

[Ch3LL]

@The-Loeki looks like i'm able to replicate this behavior with your state file. We will need to allow this to be more flexible. Thanks

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

If this issue is closed prematurely, please leave a comment and we will gladly reopen the issue.

[The-Loeki]

not stale

[stale]

Thank you for updating this issue. It is no longer marked as stale.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

If this issue is closed prematurely, please leave a comment and we will gladly reopen the issue.

[The-Loeki]

not stale again