Add use_underscores option

tests/helptext_utils.py

@@ -11,13 +11,15 @@
 import tyro._strings
 
 
-def get_helptext(f: Callable, args: List[str] = ["--help"]) -> str:
+def get_helptext(
+    f: Callable, args: List[str] = ["--help"], use_underscores: bool = False
+) -> str:
     target = io.StringIO()
     with pytest.raises(SystemExit), contextlib.redirect_stdout(target):
-        tyro.cli(f, args=args)
+        tyro.cli(f, args=args, use_underscores=use_underscores)
 
     # Check tyro.extras.get_parser().
-    parser = tyro.extras.get_parser(f)
+    parser = tyro.extras.get_parser(f, use_underscores=use_underscores)
     assert isinstance(parser, argparse.ArgumentParser)
 
     # Returned parser should have formatting information stripped. External tools rarely
@@ -44,7 +46,7 @@ def get_helptext(f: Callable, args: List[str] = ["--help"]) -> str:
     target2 = io.StringIO()
     with pytest.raises(SystemExit), contextlib.redirect_stdout(target2):
         tyro._arguments.USE_RICH = False
-        tyro.cli(f, args=args)
+        tyro.cli(f, args=args, use_underscores=use_underscores)
         tyro._arguments.USE_RICH = True
 
     if target2.getvalue() != tyro._strings.strip_ansi_sequences(target.getvalue()):

tests/test_dcargs.py

@@ -688,3 +688,34 @@ class A:
 
     assert tyro.cli(A, args="--x".split(" ")).x == ()
     assert tyro.cli(A, args="--y".split(" ")).y == []
+
+
+def test_unknown_args_with_consistent_duplicates_use_underscores() -> None:
+    @dataclasses.dataclass
+    class A:
+        a_b: List[int] = dataclasses.field(default_factory=list)
+        c_d: List[int] = dataclasses.field(default_factory=list)
+
+    # Tests logic for consistent duplicate arguments when performing argument fixing.
+    # i.e., we can fix arguments if the separator is consistent (all _'s or all -'s).
+    a, unknown_args = tyro.cli(
+        A,
+        args=[
+            "--a-b",
+            "5",
+            "--a-b",
+            "7",
+            "--c_d",
+            "5",
+            "--c_d",
+            "7",
+            "--e-f",
+            "--e-f",
+            "--g_h",
+            "--g_h",
+        ],
+        return_unknown_args=True,
+        use_underscores=True,
+    )
+    assert a == A(a_b=[7], c_d=[7])
+    assert unknown_args == ["--e-f", "--e-f", "--g_h", "--g_h"]

tests/test_dict_namedtuple.py

@@ -311,6 +311,36 @@ class HelptextNamedTuple(NamedTuple):
 
 
 def test_nested_dict() -> None:
+    loaded_config = {
+        "batch_size": 32,
+        "optimizer": {
+            "learning_rate": 1e-4,
+            "epsilon": 1e-8,
+            "scheduler": {"schedule_type": "constant"},
+        },
+    }
+    backup_config = copy.deepcopy(loaded_config)
+    overrided_config = tyro.cli(
+        dict,
+        default=loaded_config,
+        args=[
+            "--batch-size",
+            "16",
+            "--optimizer.scheduler.schedule_type",
+            "exponential",
+        ],
+    )
+
+    # Overridden config should be different from loaded config.
+    assert overrided_config != loaded_config
+    assert overrided_config["batch_size"] == 16
+    assert overrided_config["optimizer"]["scheduler"]["schedule_type"] == "exponential"
+
+    # Original loaded config should not be mutated.
+    assert loaded_config == backup_config
+
+
+def test_nested_dict_use_underscores() -> None:
     loaded_config = {
         "batch_size": 32,
         "optimizer": {
@@ -329,6 +359,7 @@ def test_nested_dict() -> None:
             "--optimizer.scheduler.schedule-type",
             "exponential",
         ],
+        use_underscores=True,
     )
 
     # Overridden config should be different from loaded config.
@@ -372,6 +403,59 @@ def test_nested_dict_hyphen() -> None:
     assert loaded_config == backup_config
 
 
+def test_nested_dict_hyphen_use_underscores() -> None:
+    # We do a lot of underscore <=> conversion in the code; this is just to make sure it
+    # doesn't break anything!
+    loaded_config = {
+        "batch-size": 32,
+        "optimizer": {
+            "learning-rate": 1e-4,
+            "epsilon": 1e-8,
+            "scheduler": {"schedule-type": "constant"},
+        },
+    }
+    backup_config = copy.deepcopy(loaded_config)
+    overrided_config = tyro.cli(
+        dict,
+        default=loaded_config,
+        args=[
+            "--batch-size",
+            "16",
+            "--optimizer.scheduler.schedule-type",
+            "exponential",
+        ],
+        use_underscores=True,
+    )
+
+    # Overridden config should be different from loaded config.
+    assert overrided_config != loaded_config
+    assert overrided_config["batch-size"] == 16
+    assert overrided_config["optimizer"]["scheduler"]["schedule-type"] == "exponential"
+
+    # Original loaded config should not be mutated.
+    assert loaded_config == backup_config
+
+    overrided_config = tyro.cli(
+        dict,
+        default=loaded_config,
+        args=[
+            "--batch_size",
+            "16",
+            "--optimizer.scheduler.schedule_type",
+            "exponential",
+        ],
+        use_underscores=True,
+    )
+
+    # Overridden config should be different from loaded config.
+    assert overrided_config != loaded_config
+    assert overrided_config["batch-size"] == 16
+    assert overrided_config["optimizer"]["scheduler"]["schedule-type"] == "exponential"
+
+    # Original loaded config should not be mutated.
+    assert loaded_config == backup_config
+
+
 def test_nested_dict_annotations() -> None:
     loaded_config = {
         "optimizer": {

tests/test_helptext.py

@@ -587,3 +587,101 @@ def main(child: Child) -> None:
 
     helptext = get_helptext(main)
     assert "--child.x | --child.no-x" in helptext
+
+
+def test_multiple_subparsers_helptext_hyphens() -> None:
+    @dataclasses.dataclass
+    class SubcommandOne:
+        """2% milk."""  # % symbol is prone to bugs in argparse.
+
+        arg_x: int = 0
+        arg_flag: bool = False
+
+    @dataclasses.dataclass
+    class SubcommandTwo:
+        arg_y: int = 1
+
+    @dataclasses.dataclass
+    class SubcommandThree:
+        arg_z: int = 2
+
+    @dataclasses.dataclass
+    class MultipleSubparsers:
+        # Field a description.
+        a: Union[SubcommandOne, SubcommandTwo, SubcommandThree]
+        # Field b description.
+        b: Union[SubcommandOne, SubcommandTwo, SubcommandThree]
+        # Field c description.
+        c: Union[SubcommandOne, SubcommandTwo, SubcommandThree] = dataclasses.field(
+            default_factory=SubcommandThree
+        )
+
+    helptext = get_helptext(MultipleSubparsers)
+
+    assert "2% milk." in helptext
+    assert "Field a description." in helptext
+    assert "Field b description." not in helptext
+    assert "Field c description." not in helptext
+
+    helptext = get_helptext(
+        MultipleSubparsers, args=["a:subcommand-one", "b:subcommand-one", "--help"]
+    )
+
+    assert "2% milk." in helptext
+    assert "Field a description." not in helptext
+    assert "Field b description." not in helptext
+    assert "Field c description." in helptext
+    assert "(default: c:subcommand-three)" in helptext
+    assert "--b.arg-x" in helptext
+    assert "--b.no-arg-flag" in helptext
+    assert "--b.arg-flag" in helptext
+
+
+def test_multiple_subparsers_helptext_underscores() -> None:
+    @dataclasses.dataclass
+    class SubcommandOne:
+        """2% milk."""  # % symbol is prone to bugs in argparse.
+
+        arg_x: int = 0
+        arg_flag: bool = False
+
+    @dataclasses.dataclass
+    class SubcommandTwo:
+        arg_y: int = 1
+
+    @dataclasses.dataclass
+    class SubcommandThree:
+        arg_z: int = 2
+
+    @dataclasses.dataclass
+    class MultipleSubparsers:
+        # Field a description.
+        a: Union[SubcommandOne, SubcommandTwo, SubcommandThree]
+        # Field b description.
+        b: Union[SubcommandOne, SubcommandTwo, SubcommandThree]
+        # Field c description.
+        c: Union[SubcommandOne, SubcommandTwo, SubcommandThree] = dataclasses.field(
+            default_factory=SubcommandThree
+        )
+
+    helptext = get_helptext(MultipleSubparsers, use_underscores=True)
+
+    assert "2% milk." in helptext
+    assert "Field a description." in helptext
+    assert "Field b description." not in helptext
+    assert "Field c description." not in helptext
+
+    helptext = get_helptext(
+        MultipleSubparsers,
+        args=["a:subcommand_one", "b:subcommand_one", "--help"],
+        use_underscores=True,
+    )
+
+    assert "2% milk." in helptext
+    assert "Field a description." not in helptext
+    assert "Field b description." not in helptext
+    assert "Field c description." in helptext
+    assert "(default: c:subcommand_three)" in helptext
+    assert "--b.arg_x" in helptext
+    assert "--b.no_arg_flag" in helptext
+    assert "--b.arg_flag" in helptext

tyro/_arguments.py

@@ -67,11 +67,13 @@ def __init__(
 
             if option_string.startswith("--"):
                 if "." not in option_string:
-                    option_string = "--no-" + option_string[2:]
+                    option_string = (
+                        "--no" + _strings.get_delimeter() + option_string[2:]
+                    )
                 else:
-                    # Loose heuristic for where to add the no- prefix.
+                    # Loose heuristic for where to add the no-/no_ prefix.
                     left, _, right = option_string.rpartition(".")
-                    option_string = left + ".no-" + right
+                    option_string = left + ".no" + _strings.get_delimeter() + right
                 self._no_strings.add(option_string)
 
                 _option_strings.append(option_string)