gh-142389: Add support for backtick colorisation in argparse help text

Doc/library/argparse.rst

@@ -637,25 +637,21 @@ are set.
 
 .. versionadded:: 3.14
 
-To highlight inline code in your description or epilog text, you can use
-backticks::
+To highlight inline code in your description, epilog, or argument ``help``
+text, you can use backticks::
 
    >>> parser = argparse.ArgumentParser(
    ...     formatter_class=argparse.RawDescriptionHelpFormatter,
    ...     epilog='''Examples:
    ...   `python -m myapp --verbose`
    ...   `python -m myapp --config settings.json`
    ... ''')
+   >>> parser.add_argument('--foo', help='set the `foo` value')
 
 When colors are enabled, the text inside backticks will be displayed in a
 distinct color to help examples stand out. When colors are disabled, backticks
 are preserved as-is, which is readable in plain text.
 
-.. note::
-
-   Backtick markup only applies to description and epilog text. It does not
-   apply to individual argument ``help`` strings.
-
 .. versionadded:: 3.15
 
 

Doc/whatsnew/3.15.rst

@@ -715,9 +715,9 @@ argparse
   default to ``True``. This enables suggestions for mistyped arguments by default.
   (Contributed by Jakob Schluse in :gh:`140450`.)
 
-* Added backtick markup support in description and epilog text to highlight
+* Added backtick markup support in help text to highlight
   inline code when color output is enabled.
-  (Contributed by Savannah Ostrowski in :gh:`142390`.)
+  (Contributed by Savannah Ostrowski and Hugo van Kemenade in :gh:`142389`.)
 
 
 array

Lib/argparse.py

@@ -682,7 +682,7 @@ def _format_args(self, action, default_metavar):
     def _expand_help(self, action):
         help_string = self._get_help_string(action)
         if '%' not in help_string:
-            return help_string
+            return self._apply_text_markup(help_string)
         params = dict(vars(action), prog=self._prog)
         for name in list(params):
             value = params[name]
@@ -726,7 +726,9 @@ def colorize(match):
             # bare %s etc. - format with full params dict, no colorization
             return spec % params
 
-        return _re.sub(fmt_spec, colorize, help_string, flags=_re.VERBOSE)
+        return self._apply_text_markup(
+            _re.sub(fmt_spec, colorize, help_string, flags=_re.VERBOSE)
+        )
 
     def _iter_indented_subactions(self, action):
         try:

Lib/test/libregrtest/cmdline.py

@@ -245,7 +245,7 @@ def _create_parser():
                             'buildbot workers')
     group.add_argument('--timeout', metavar='TIMEOUT',
                         help='dump the traceback and exit if a test takes '
-                             'more than TIMEOUT seconds; disabled if TIMEOUT '
+                             'more than `TIMEOUT` seconds; disabled if `TIMEOUT` '
                              'is negative or equals to zero')
     group.add_argument('--wait', action='store_true',
                        help='wait for user input, e.g., allow a debugger '
@@ -261,11 +261,11 @@ def _create_parser():
 
     group = parser.add_argument_group('Verbosity')
     group.add_argument('-v', '--verbose', action='count',
-                       help='run tests in verbose mode with output to stdout')
+                       help='run tests in verbose mode with output to `stdout`')
     group.add_argument('-w', '--rerun', action='store_true',
                        help='re-run failed tests in verbose mode')
     group.add_argument('--verbose2', action='store_true', dest='rerun',
-                       help='deprecated alias to --rerun')
+                       help='deprecated alias to `--rerun`')
     group.add_argument('-W', '--verbose3', action='store_true',
                        help='display test output on failure')
     group.add_argument('-q', '--quiet', action='store_true',
@@ -295,22 +295,22 @@ def _create_parser():
                             more_details)
     group.add_argument('-m', '--match', metavar='PAT',
                        dest='match_tests', action=FilterAction, const=True,
-                       help='match test cases and methods with glob pattern PAT')
+                       help='match test cases and methods with glob pattern `PAT`')
     group.add_argument('-i', '--ignore', metavar='PAT',
                        dest='match_tests', action=FilterAction, const=False,
-                       help='ignore test cases and methods with glob pattern PAT')
+                       help='ignore test cases and methods with glob pattern `PAT`')
     group.add_argument('--matchfile', metavar='FILENAME',
                        dest='match_tests',
                        action=FromFileFilterAction, const=True,
-                       help='similar to --match but get patterns from a '
+                       help='similar to `--match` but get patterns from a '
                             'text file, one pattern per line')
     group.add_argument('--ignorefile', metavar='FILENAME',
                        dest='match_tests',
                        action=FromFileFilterAction, const=False,
-                       help='similar to --matchfile but it receives patterns '
+                       help='similar to `--matchfile` but it receives patterns '
                             'from text file to ignore')
     group.add_argument('-G', '--failfast', action='store_true',
-                       help='fail as soon as a test fails (only with -v or -W)')
+                       help='fail as soon as a test fails (only with `-v` or `-W`)')
     group.add_argument('-u', '--use', metavar='RES1,RES2,...',
                        action='extend', type=resources_list,
                        help='specify which special resource intensive tests '
@@ -325,28 +325,28 @@ def _create_parser():
 
     group = parser.add_argument_group('Special runs')
     group.add_argument('-L', '--runleaks', action='store_true',
-                       help='run the leaks(1) command just before exit.' +
+                       help='run the `leaks(1)` command just before exit.' +
                             more_details)
     group.add_argument('-R', '--huntrleaks', metavar='RUNCOUNTS',
                        type=huntrleaks,
                        help='search for reference leaks (needs debug build, '
                             'very slow).' + more_details)
     group.add_argument('-j', '--multiprocess', metavar='PROCESSES',
                        dest='use_mp', type=int,
-                       help='run PROCESSES processes at once')
+                       help='run `PROCESSES` processes at once')
     group.add_argument('--single-process', action='store_true',
                        dest='single_process',
                        help='always run all tests sequentially in '
-                            'a single process, ignore -jN option, '
+                            'a single process, ignore `-jN` option, '
                             'and failed tests are also rerun sequentially '
                             'in the same process')
     group.add_argument('--parallel-threads', metavar='PARALLEL_THREADS',
                        type=int,
-                       help='run copies of each test in PARALLEL_THREADS at '
+                       help='run copies of each test in `PARALLEL_THREADS` at '
                             'once')
     group.add_argument('-T', '--coverage', action='store_true',
                        dest='trace',
-                       help='turn on code coverage tracing using the trace '
+                       help='turn on code coverage tracing using the `trace` '
                             'module')
     group.add_argument('-D', '--coverdir', metavar='DIR',
                        type=relative_filename,
@@ -356,18 +356,18 @@ def _create_parser():
                        help='put coverage files alongside modules')
     group.add_argument('-t', '--threshold', metavar='THRESHOLD',
                        type=int,
-                       help='call gc.set_threshold(THRESHOLD)')
+                       help='call `gc.set_threshold(THRESHOLD)`')
     group.add_argument('-n', '--nowindows', action='store_true',
                        help='suppress error message boxes on Windows')
     group.add_argument('-F', '--forever', action='store_true',
                        help='run the specified tests in a loop, until an '
-                            'error happens; imply --failfast')
+                            'error happens; imply `--failfast`')
     group.add_argument('--list-tests', action='store_true',
                        help="only write the name of tests that will be run, "
                             "don't execute them")
     group.add_argument('--list-cases', action='store_true',
-                       help='only write the name of test cases that will be run'
-                            ' , don\'t execute them')
+                       help='only write the name of test cases that will be run, '
+                            'don\'t execute them')
     group.add_argument('-P', '--pgo', dest='pgo', action='store_true',
                        help='enable Profile Guided Optimization (PGO) training')
     group.add_argument('--pgo-extended', action='store_true',
@@ -390,11 +390,11 @@ def _create_parser():
     group.add_argument('--tempdir', metavar='PATH',
                        help='override the working directory for the test run')
     group.add_argument('--cleanup', action='store_true',
-                       help='remove old test_python_* directories')
+                       help='remove old `test_python_*` directories')
     group.add_argument('--bisect', action='store_true',
-                       help='if some tests fail, run test.bisect_cmd on them')
+                       help='if some tests fail, run `test.bisect_cmd` on them')
     group.add_argument('--pythoninfo', action='store_true',
-                       help="run python -m test.pythoninfo before tests")
+                       help="run `python -m test.pythoninfo` before tests")
     group.add_argument('--dont-add-python-opts', dest='_add_python_opts',
                        action='store_false',
                        help="internal option, don't use it")

Lib/test/test_argparse.py

@@ -7696,6 +7696,37 @@ def test_backtick_markup_special_regex_chars(self):
         help_text = parser.format_help()
         self.assertIn(f'{prog_extra}grep "foo.*bar" | sort{reset}', help_text)
 
+    def test_backtick_markup_in_argument_help(self):
+        parser = argparse.ArgumentParser(prog="PROG", color=True)
+        parser.add_argument("--foo", help="set the `foo` value")
+
+        prog_extra = self.theme.prog_extra
+        reset = self.theme.reset
+
+        help_text = parser.format_help()
+        self.assertIn(f"set the {prog_extra}foo{reset} value", help_text)
+        self.assertNotIn("`", help_text)
+
+    def test_backtick_markup_in_argument_help_with_format(self):
+        parser = argparse.ArgumentParser(prog="PROG", color=True)
+        parser.add_argument(
+            "--foo", default="bar", help="set `foo` (default: %(default)s)"
+        )
+
+        prog_extra = self.theme.prog_extra
+        reset = self.theme.reset
+
+        help_text = parser.format_help()
+        self.assertIn(f"set {prog_extra}foo{reset}", help_text)
+
+    def test_backtick_markup_in_argument_help_color_disabled(self):
+        parser = argparse.ArgumentParser(prog="PROG", color=False)
+        parser.add_argument("--foo", help="set the `foo` value")
+
+        help_text = parser.format_help()
+        self.assertIn("set the `foo` value", help_text)
+        self.assertNotIn("\x1b[", help_text)
+
     def test_help_with_format_specifiers(self):
         # GH-142950: format specifiers like %x should work with color=True
         parser = argparse.ArgumentParser(prog='PROG', color=True)

Misc/NEWS.d/next/Library/2026-05-04-18-01-35.gh-issue-142389.4Faqpq.rst

@@ -0,0 +1,2 @@
+Add backtick markup support in :mod:`argparse` option help text to highlight
+inline code when color output is enabled. Patch by Hugo van Kemenade.