Fix color of brackets surrounding positional arguments in the usage

.vscode/cspell.json

@@ -11,11 +11,22 @@
         "isort",
         "kwargs",
         "kwds",
+        "mbar",
+        "mdescription",
+        "mepilog",
         "mfile",
+        "mfoo",
         "mmiddle",
+        "moom",
+        "moptional",
+        "mparser",
+        "mremainder",
+        "mrequired",
         "mshow",
+        "msuppress",
         "msyntax",
         "mypy",
+        "mzom",
         "positionals",
         "pypi",
         "pyproject",

CHANGELOG.md

@@ -19,6 +19,10 @@
 - Allow arbitrary renderables in the descriptions and epilog
   * PR [#99](https://github.com/hamdanal/rich-argparse/pull/99)
 
+### Fixes
+- Fix color of brackets surrounding positional arguments in the usage.
+  * Issue [#100](https://github.com/hamdanal/rich-argparse/issues/100),
+    PR [#101](https://github.com/hamdanal/rich-argparse/pull/101)
 ## 1.3.0 - 2023-08-19
 
 ### Features

rich_argparse/__init__.py

@@ -272,7 +272,7 @@ def _rich_prog_spans(self, usage: str) -> Iterator[r.Span]:
             last = end
             yield r.Span(prog_start, prog_end, "argparse.prog")
 
-    def _rich_usage_spans(
+    def _rich_usage_spans(  # noqa: C901
         self, text: str, start: int, actions: Iterable[Action]
     ) -> Iterator[r.Span]:
         options: list[Action] = []
@@ -307,10 +307,30 @@ def find_span(_string: str) -> tuple[int, int]:
                 yield r.Span(start, end, "argparse.metavar")
             pos = end + 1
         for action in positionals:  # positionals come at the end
-            usage = self._format_args(action, self._get_default_metavar_for_positional(action))
-            start, end = find_span(usage)
-            yield r.Span(start, end, "argparse.args")
-            pos = end + 1
+            metavar = self._get_default_metavar_for_positional(action)
+            metavar_tuple = self._metavar_formatter(action, metavar)(1)
+            usage = metavar_tuple[0]
+            if isinstance(action.nargs, int):
+                nargs = action.nargs
+            elif action.nargs in (argparse.REMAINDER, argparse.SUPPRESS):
+                nargs = 0
+            elif action.nargs in (None, argparse.OPTIONAL, argparse.PARSER):
+                nargs = 1
+            elif action.nargs == argparse.ZERO_OR_MORE:
+                if sys.version_info >= (3, 9):  # pragma: >=3.9 cover
+                    nargs = 2 if len(metavar_tuple) == 2 else 1
+                else:  # pragma: <3.9 cover
+                    nargs = 2
+            elif action.nargs == argparse.ONE_OR_MORE:
+                nargs = 2
+            else:  # pragma: no cover
+                # unknown nargs, fallback to coloring the whole thing
+                usage = self._format_args(action, metavar)
+                nargs = 1
+            for _ in range(nargs):
+                start, end = find_span(usage)
+                yield r.Span(start, end, "argparse.args")
+                pos = end + 1
 
     def _rich_whitespace_sub(self, text: r.Text) -> r.Text:
         # do this `self._whitespace_matcher.sub(' ', text).strip()` but text is Text

tests/test_argparse.py

@@ -383,28 +383,43 @@ def test_user_usage(usage, expected, usage_markup):
 @pytest.mark.usefixtures("force_color")
 def test_actions_spans_in_usage():
     parser = ArgumentParser("PROG", formatter_class=RichHelpFormatter)
-    parser.add_argument("arg", nargs="*")
+    parser.add_argument("required")
+    parser.add_argument("int", nargs=2)
+    parser.add_argument("optional", nargs=argparse.OPTIONAL)
+    parser.add_argument("zom", nargs=argparse.ZERO_OR_MORE)
+    parser.add_argument("oom", nargs=argparse.ONE_OR_MORE)
+    parser.add_argument("remainder", nargs=argparse.REMAINDER)
+    parser.add_argument("parser", nargs=argparse.PARSER)
+    parser.add_argument("suppress", nargs=argparse.SUPPRESS)
     mut_ex = parser.add_mutually_exclusive_group()
     mut_ex.add_argument("--opt", nargs="?")
     mut_ex.add_argument("--opts", nargs="+")
 
     # https://github.com/python/cpython/issues/82619
     if sys.version_info < (3, 9):  # pragma: <3.9 cover
-        arg_metavar = "[arg [arg ...]]"
+        zom_metavar = "[\x1b[36mzom\x1b[0m [\x1b[36mzom\x1b[0m ...]]"
     else:  # pragma: >=3.9 cover
-        arg_metavar = "[arg ...]"
+        zom_metavar = "[\x1b[36mzom\x1b[0m ...]"
 
     usage_text = (
         f"\x1b[38;5;208mUsage:\x1b[0m \x1b[38;5;244mPROG\x1b[0m [\x1b[36m-h\x1b[0m] "
         f"[\x1b[36m--opt\x1b[0m \x1b[38;5;36m[OPT]\x1b[0m | "
-        f"\x1b[36m--opts\x1b[0m \x1b[38;5;36mOPTS [OPTS ...]\x1b[0m] "
-        f"\x1b[36m{arg_metavar}\x1b[0m"
+        f"\x1b[36m--opts\x1b[0m \x1b[38;5;36mOPTS [OPTS ...]\x1b[0m]\n                "
+        f"\x1b[36mrequired\x1b[0m \x1b[36mint\x1b[0m \x1b[36mint\x1b[0m [\x1b[36moptional\x1b[0m] "
+        f"{zom_metavar} \x1b[36moom\x1b[0m [\x1b[36moom\x1b[0m ...] ... \x1b[36mparser\x1b[0m ..."
     )
     expected_help_output = f"""\
     {usage_text}
 
     \x1b[38;5;208mPositional Arguments:\x1b[0m
-      \x1b[36marg\x1b[0m
+      \x1b[36mrequired\x1b[0m
+      \x1b[36mint\x1b[0m
+      \x1b[36moptional\x1b[0m
+      \x1b[36mzom\x1b[0m
+      \x1b[36moom\x1b[0m
+      \x1b[36mremainder\x1b[0m
+      \x1b[36mparser\x1b[0m
+      \x1b[36msuppress\x1b[0m
 
     \x1b[38;5;208mOptional Arguments:\x1b[0m
       \x1b[36m-h\x1b[0m, \x1b[36m--help\x1b[0m            \x1b[39mshow this help message and exit\x1b[0m
@@ -706,7 +721,7 @@ def test_subparsers_usage():
     rich_child2 = rich_subparsers.add_parser("sp2")
     assert rich_parent.format_usage() == (
         "\x1b[38;5;208mUsage:\x1b[0m \x1b[38;5;244mPROG\x1b[0m [\x1b[36m-h\x1b[0m] "
-        "\x1b[36m{sp1,sp2} ...\x1b[0m\n"
+        "\x1b[36m{sp1,sp2}\x1b[0m ...\n"
     )
     assert rich_child1.format_usage() == (
         "\x1b[38;5;208mUsage:\x1b[0m \x1b[38;5;244mPROG sp1\x1b[0m [\x1b[36m-h\x1b[0m]\n"