Merge pull request #1126 from mulkieran/print-all-help-option

Add secret command-line option to print all help text

src/stratis_cli/_parser/_parser.py

@@ -33,6 +33,7 @@
 from ._logical import LOGICAL_SUBCMDS
 from ._physical import PHYSICAL_SUBCMDS
 from ._pool import POOL_SUBCMDS
+from ._range import PrintHelpAction
 
 
 def print_help(parser):
@@ -213,6 +214,11 @@ def gen_parser():
     # version is special, it has explicit support in argparse
     parser.add_argument("--version", action="version", version=__version__)
 
+    # --print-all-help is special because it introspects on the parser
+    parser.add_argument(
+        "--print-all-help", action=PrintHelpAction, help=argparse.SUPPRESS, nargs=0
+    )
+
     _add_args(parser, GEN_ARGS)
 
     subparsers = parser.add_subparsers(title="subcommands")

src/stratis_cli/_parser/_range.py

@@ -18,6 +18,7 @@
 # isort: STDLIB
 import argparse
 import re
+import sys
 
 # isort: THIRDPARTY
 from justbytes import B, GiB, KiB, MiB, PiB, Range, TiB
@@ -98,3 +99,35 @@ class DefaultAction(argparse.Action):
     def __call__(self, parser, namespace, values, option_string=None):
         setattr(namespace, self.dest, values)
         setattr(namespace, self.dest + "_default", False)
+
+
+def gen_subparsers(parser, command_line):
+    """
+    Yield all subparser/command_lines pairs for this parser and this prefix
+    command line.
+
+    :param parser: an argparse parser
+    :param command_line: a prefix command line
+    :type command_line: list of str
+    """
+    yield (parser, command_line)
+    for action in (
+        action
+        for action in parser._actions  # pylint: disable=protected-access
+        if isinstance(
+            action, argparse._SubParsersAction  # pylint: disable=protected-access
+        )
+    ):
+        for name, subparser in sorted(action.choices.items(), key=lambda x: x[0]):
+            yield from gen_subparsers(subparser, command_line + [name])
+
+
+class PrintHelpAction(argparse.Action):
+    """
+    Print the help text for every subcommand.
+    """
+
+    def __call__(self, parser, namespace, values, option_string=None):
+        for subparser, _ in gen_subparsers(parser, []):
+            subparser.print_help()
+        sys.exit(0)

tests/whitebox/integration/test_parser.py

@@ -15,6 +15,10 @@
 Test command-line argument parsing.
 """
 
+# isort: STDLIB
+from io import StringIO
+from unittest import mock
+
 # isort: LOCAL
 from stratis_cli import StratisCliErrorCodes
 
@@ -432,3 +436,16 @@ def test_stratis_list_default(self):
         for subcommand in [["pool"], ["filesystem"], ["blockdev"]]:
             for prefix in [[], ["--propagate"]]:
                 self.assertEqual(RUNNER(prefix + subcommand), 0)
+
+
+class TestAllHelp(RunTestCase):
+    """
+    Verify that --print-all-help option succeeds.
+    """
+
+    def test_print_all_help(self):
+        """
+        Test the --print-all-help option.
+        """
+        with mock.patch("sys.stdout", new=StringIO()):
+            self.check_system_exit(["--print-all-help"], 0)