Minor test, readme updates

README.md

@@ -38,8 +38,10 @@
 
 <br />
 
-<strong><code>tyro.cli()</code></strong> generates command-line interfaces via
-Python type introspection. We can define configurable scripts using functions:
+<strong><code>tyro.cli()</code></strong> is a tool for generating CLI
+interfaces.
+
+We can define configurable scripts using functions:
 
 ```python
 """A command-line interface defined using a function signature.
@@ -60,7 +62,7 @@ if __name__ == "__main__":
     tyro.cli(main)
 ```
 
-Or instantiate configuration objects defined using tools like `dataclasses`, `pydantic`, and `attrs`:
+Or instantiate config objects defined using tools like `dataclasses`, `pydantic`, and `attrs`:
 
 ```python
 """A command-line interface defined using a class signature.
@@ -84,8 +86,8 @@ if __name__ == "__main__":
     assert isinstance(config, Config)  # Should pass.
 ```
 
-Other features include helptext generation, nested structures, shell
-completion, and subcommands. For examples and the API reference, see our
+Other features include helptext generation, nested structures, subcommands, and
+shell completion. For examples and the API reference, see our
 [documentation](https://brentyi.github.io/tyro).
 
 ### In the wild

tests/test_dcargs.py

@@ -307,6 +307,17 @@ class A:
         assert tyro.cli(A, args=["--x", "3"])
 
 
+def test_literal_none() -> None:
+    @dataclasses.dataclass
+    class A:
+        x: Literal[0, 1, None, 2]
+
+    assert tyro.cli(A, args=["--x", "1"]) == A(x=1)
+    assert tyro.cli(A, args=["--x", "None"]) == A(x=None)
+    with pytest.raises(SystemExit):
+        assert tyro.cli(A, args=["--x", "3"])
+
+
 Choices = int
 Choices = tyro.extras.literal_type_from_choices([0, 1, 2])  # type: ignore
 

tests/test_py311_generated/test_completion_generated.py

@@ -1,6 +1,7 @@
 import contextlib
 import dataclasses
 import io
+from typing import Annotated, Literal, Optional
 
 import pytest
 
@@ -40,3 +41,34 @@ def test_zsh():
     with pytest.raises(SystemExit), contextlib.redirect_stdout(target):
         tyro.cli(Wrapper, args=["--tyro-print-completion", "zsh"])
     assert "# AUTOMATICALLY GENERATED by `shtab`" in target.getvalue()
+
+
+def test_completion_zsh():
+    """https://github.com/brentyi/tyro/issues/158"""
+
+    def start_device(
+        preset: Annotated[
+            Optional[Literal["rgb", "depth", "ir"]], tyro.conf.arg(aliases=["-p"])
+        ] = None,
+        frame: Annotated[
+            Literal["world", "base"], tyro.conf.arg(aliases=["-f"])
+        ] = "world",
+    ) -> None:
+        """
+        Start device with the given preset.
+
+        :param preset: device preset to use.
+        :param frame: coordinate frame to use.
+        """
+
+    target = io.StringIO()
+    with pytest.raises(SystemExit), contextlib.redirect_stdout(target):
+        tyro.cli(start_device, args=["--tyro-print-completion", "bash"])
+
+    completion_script = target.getvalue()
+    print(completion_script)
+    assert "# AUTOMATICALLY GENERATED by `shtab`" in completion_script
+    assert "preset_choices=(" in completion_script
+    assert "p_choices=(" in completion_script
+    assert "frame_choices=(" in completion_script
+    assert "f_choices=(" in completion_script

tests/test_py311_generated/test_dcargs_generated.py

@@ -309,6 +309,17 @@ class A:
         assert tyro.cli(A, args=["--x", "3"])
 
 
+def test_literal_none() -> None:
+    @dataclasses.dataclass
+    class A:
+        x: Literal[0, 1, None, 2]
+
+    assert tyro.cli(A, args=["--x", "1"]) == A(x=1)
+    assert tyro.cli(A, args=["--x", "None"]) == A(x=None)
+    with pytest.raises(SystemExit):
+        assert tyro.cli(A, args=["--x", "3"])
+
+
 Choices = int
 Choices = tyro.extras.literal_type_from_choices([0, 1, 2])  # type: ignore