Add check mode support to ansible-pull (#28021)

Fixes #27989

lib/ansible/cli/pull.py

@@ -107,6 +107,8 @@ class PullCLI(CLI):
                                help='modified files in the working repository will be discarded')
         self.parser.add_option('--track-subs', dest='tracksubs', default=False, action='store_true',
                                help='submodules will track the latest changes. This is equivalent to specifying the --remote flag to git submodule update')
+        self.parser.add_option("--check", default=False, dest='check', action='store_true',
+                               help="don't make any changes; instead, try to predict some of the changes that may occur")
 
         # for pull we don't want a default
         self.parser.set_defaults(inventory=None)
@@ -243,6 +245,8 @@ class PullCLI(CLI):
             cmd += ' -l "%s"' % self.options.subset
         else:
             cmd += ' -l "%s"' % limit_opts
+        if self.options.check:
+            cmd += ' -C'
 
         os.chdir(self.options.dest)