Support recursive argument suppression

src/tyro/_arguments.py

@@ -110,6 +110,15 @@ class ArgumentDefinition:
     subcommand_prefix: str  # Prefix for nesting.
     field: _fields.FieldDefinition
 
+    def __post_init__(self) -> None:
+        if (
+            _markers.Fixed in self.field.markers
+            or _markers.Suppress in self.field.markers
+        ) and self.field.default in _singleton.MISSING_AND_MISSING_NONPROP:
+            raise UnsupportedTypeAnnotationError(
+                f"Field {self.field.intern_name} is missing a default value!"
+            )
+
     def add_argument(
         self, parser: Union[argparse.ArgumentParser, argparse._ArgumentGroup]
     ) -> None:

src/tyro/_fields.py

@@ -16,9 +16,7 @@
 from ._singleton import MISSING_AND_MISSING_NONPROP, MISSING_NONPROP
 from ._typing import TypeForm
 from .conf import _confstruct, _markers
-from .constructors._primitive_spec import (
-    UnsupportedTypeAnnotationError,
-)
+from .constructors._primitive_spec import UnsupportedTypeAnnotationError
 from .constructors._registry import ConstructorRegistry
 from .constructors._struct_spec import (
     StructFieldSpec,
@@ -51,14 +49,6 @@ class FieldDefinition:
     # doesn't match the keyword expected by our callable.
     call_argname: Any
 
-    def __post_init__(self):
-        if (
-            _markers.Fixed in self.markers or _markers.Suppress in self.markers
-        ) and self.default in MISSING_AND_MISSING_NONPROP:
-            raise UnsupportedTypeAnnotationError(
-                f"Field {self.intern_name} is missing a default value!"
-            )
-
     @staticmethod
     @contextlib.contextmanager
     def marker_context(markers: Tuple[_markers.Marker, ...]):

src/tyro/_parsers.py

@@ -354,11 +354,7 @@ def handle_field(
         field.type, field.markers, nondefault_only=True
     )
 
-    if (
-        not force_primitive
-        and _markers.Fixed not in field.markers
-        and _markers.Suppress not in field.markers
-    ):
+    if not force_primitive:
         # (1) Handle Unions over callables; these result in subparsers.
         subparsers_attempt = SubparsersSpecification.from_field(
             field,
@@ -367,9 +363,9 @@ def handle_field(
             extern_prefix=_strings.make_field_name([extern_prefix, field.extern_name]),
         )
         if subparsers_attempt is not None:
-            if (
-                not subparsers_attempt.required
-                and _markers.AvoidSubcommands in field.markers
+            if not subparsers_attempt.required and (
+                _markers.AvoidSubcommands in field.markers
+                or _markers.Suppress in field.markers
             ):
                 # Don't make a subparser.
                 field = field.with_new_type_stripped(type(field.default))

tests/test_conf.py

@@ -1545,3 +1545,16 @@ def main(
         # Doesn't work in Python 3.7 because of argparse limitations.
         assert tyro.cli(main, args="--verbosity --verbosity -vv".split(" ")) == (2, 2)
         assert tyro.cli(main, args="--verbosity --verbosity -vvv".split(" ")) == (2, 3)
+
+
+def test_nested_suppress() -> None:
+    @dataclasses.dataclass
+    class Bconfig:
+        b: int = 1
+
+    @dataclasses.dataclass
+    class Aconfig:
+        a: str = "hello"
+        b_conf: Bconfig = dataclasses.field(default_factory=Bconfig)
+
+    assert tyro.cli(Aconfig, config=(tyro.conf.Suppress,), args=[]) == Aconfig()

tests/test_py311_generated/test_conf_generated.py

@@ -1540,3 +1540,16 @@ def main(
         # Doesn't work in Python 3.7 because of argparse limitations.
         assert tyro.cli(main, args="--verbosity --verbosity -vv".split(" ")) == (2, 2)
         assert tyro.cli(main, args="--verbosity --verbosity -vvv".split(" ")) == (2, 3)
+
+
+def test_nested_suppress() -> None:
+    @dataclasses.dataclass
+    class Bconfig:
+        b: int = 1
+
+    @dataclasses.dataclass
+    class Aconfig:
+        a: str = "hello"
+        b_conf: Bconfig = dataclasses.field(default_factory=Bconfig)
+
+    assert tyro.cli(Aconfig, config=(tyro.conf.Suppress,), args=[]) == Aconfig()