arg fixes.

borgmatic/borg/diff.py

@@ -67,9 +67,9 @@ def diff(
                 else flags.make_repository_flags(repository, local_borg_version)
             )
         )
-        + (('--same-chunker-params', diff_arguments.timestamp) if diff_arguments.same_chunker_params else ())
+        + (('--same-chunker-params',) if diff_arguments.same_chunker_params else ())
         + (('--sort-by', diff_arguments.sort_by) if diff_arguments.sort_by else ())
-        + (('--content-only', diff_arguments.content_only) if diff_arguments.content_only else ())
+        + (('--content-only',) if diff_arguments.content_only else ())
         + (diff_arguments.second_archive, )
     )
 

borgmatic/commands/arguments.py

@@ -1992,19 +1992,22 @@ def make_parsers(schema, unparsed_arguments):  # noqa: PLR0915
     )
     diff_group.add_argument(
         '--numeric-ids',
+        action='store_true',
         help='Only consider numeric user and group identifiers',
     )
     diff_group.add_argument(
         '--same-chunker-params',
+        action='store_true',
         help='Override check of chunker parameters'
     )
     diff_group.add_argument(
         '--sort-by',
-        metavar='FIELD[,FIELD...]',
+        metavar='KEYS',
         help='Advanced sorting: specify field(s) to sort by. Accepts a comma-separated list. Prefix with > for descending or < for ascending (default).'
     )
     diff_group.add_argument(
         '--content-only',
+        action='store_true',
         help='Only compare differences in content (exclude metadata differences)'
     )
     borg_parser = action_parsers.add_parser(