Fill out svn state

single quotes
add a top doc string
use .format
add import comments

salt/states/svn.py

@@ -1,18 +1,36 @@
+'''
+Manage SVN repositories
+=======================
+
+Manage repositiry checkouts via the svn vcs system:
+
+.. code-block:: yaml
+
+    http://unladen-swallow.googlecode.com/svn/trunk/:
+      svn.latest:
+        - target: /tmp/swallow
+'''
+
+# Import Python libs
 import logging
 import os
+
+# Import Salt libs
 from salt import exceptions
 from salt.states.git import _fail, _neutral_test
 
 log = logging.getLogger(__name__)
 
+
 def __virtual__():
     '''
     Only load if svn is available
     '''
-    if __salt__["cmd.has_exec"]("svn"):
-        return "svn"
+    if __salt__['cmd.has_exec']('svn'):
+        return 'svn'
     return False
 
+
 def latest(name,
            target=None,
            rev=None,
@@ -20,7 +38,7 @@ def latest(name,
            username=None,
            force=None,
            externals=True):
-    """
+    '''
     Checkout or update the working directory to the latest revision from the
     remote repository.
 
@@ -47,46 +65,46 @@ def latest(name,
 
     externals : True
         Change to False to not checkout or update externals
-    """
+    '''
     ret = {'name': name, 'result': True, 'comment': '', 'changes': {}}
     if not target:
-        return _fail(ret, '"target option is required')
+        return _fail(ret, 'Target option is required')
 
-    svn_cmd = "svn.checkout"
+    svn_cmd = 'svn.checkout'
     cwd, basename = os.path.split(target)
     opts = tuple()
 
     if os.path.exists(target) and not os.path.isdir(target):
         return _fail(ret,
-                "The path, %s, exists and is not a directory." % target)
+                'The path "{0}" exists and is not a directory.'.format(target))
 
     try:
-        __salt__["svn.info"](".", target, user=user)
-        svn_cmd = "svn.update"
+        __salt__['svn.info']('.', target, user=user)
+        svn_cmd = 'svn.update'
     except exceptions.CommandExecutionError:
         pass
 
     if rev:
-        opts += ("-r", str(rev))
+        opts += ('-r', str(rev))
 
     if force:
-        opts += ("--force",)
+        opts += ('--force',)
 
     if externals is False:
-        opts += ("--ignore-externals",)
+        opts += ('--ignore-externals',)
 
-    if svn_cmd == "svn.update":
+    if svn_cmd == 'svn.update':
         out = __salt__[svn_cmd](cwd, basename, user, *opts)
     else:
         out = __salt__[svn_cmd](cwd, name, basename, user, username, *opts)
-    ret["comment"] = out
+    ret['comment'] = out
     return ret
 
 def dirty(target,
           user=None,
           ignore_unversioned=False):
-    """
+    '''
     Determine if the working directory has been changed.
-    """
+    '''
     ret = {'name': name, 'result': True, 'comment': '', 'changes': {}}
-    return _fail(ret, "This function is not implemented yet.")
+    return _fail(ret, 'This function is not implemented yet.')