Figured out how to detect the second tab press. Writing parameter hinting to stderr to bypass bash completion handling.

Author: anselor

cmd2/argcomplete_bridge.py

@@ -228,15 +228,14 @@ def __call__(self, argument_parser, completer=None, always_complete_options=True
                 output_stream.write(ifs.join(completions).encode(argcomplete.sys_encoding))
             elif outstr:
                 # if there are no completions, but we got something from stdout, try to print help
-
                 # trick the bash completion into thinking there are 2 completions that are unlikely
                 # to ever match.
-                outstr = outstr.replace('\n', ' ').replace('\t', ' ').replace('    ', ' ').strip()
-                # generate a filler entry that should always sort first
-                filler = ' {0:><{width}}'.format('', width=len(outstr)/2)
-                outstr = ifs.join([filler, outstr])
 
-                output_stream.write(outstr.encode(argcomplete.sys_encoding))
+                comp_type = int(os.environ["COMP_TYPE"])
+                if comp_type == 63:  # type is 63 for second tab press
+                    print(outstr.rstrip(), file=argcomplete.debug_stream, end='')
+
+                output_stream.write(ifs.join([ifs, ' ']).encode(argcomplete.sys_encoding))
             else:
                 # if completions is None we assume we don't know how to handle it so let bash
                 # go forward with normal filesystem completion

cmd2/argparse_completer.py

@@ -877,7 +877,9 @@ def _match_argument(self, action, arg_strings_pattern):
 
         return super(ACArgumentParser, self)._match_argument(action, arg_strings_pattern)
 
-    def _parse_known_args(self, arg_strings, namespace):
+    # This is the official python implementation with a 5 year old patch applied
+    # See the comment below describing the patch
+    def _parse_known_args(self, arg_strings, namespace):  # pragma: no cover
         # replace arg strings that are file references
         if self.fromfile_prefix_chars is not None:
             arg_strings = self._read_args_from_files(arg_strings)