Enable cli tab completion (#317)

Author: cidrblock

.config/requirements-test.in

@@ -1,3 +1,4 @@
+argcomplete
 coverage[toml]
 mypy
 pip-tools

.pre-commit-config.yaml

@@ -80,6 +80,7 @@ repos:
         args:
           - --output-format=colorized
         additional_dependencies:
+          - argcomplete
           - pytest
           - pyyaml
           - subprocess_tee
@@ -91,6 +92,7 @@ repos:
     hooks:
       - id: mypy
         additional_dependencies:
+          - argcomplete
           - pip
           - pytest
           - subprocess_tee

src/ansible_dev_environment/arg_parser.py

@@ -16,6 +16,14 @@
 from .utils import str_to_bool
 
 
+try:
+    import argcomplete
+
+    HAS_ARGCOMPLETE = True
+except ImportError:  # pragma: no cover
+    HAS_ARGCOMPLETE = False
+
+
 logger = logging.getLogger(__name__)
 
 if TYPE_CHECKING:
@@ -255,6 +263,9 @@ def parse() -> argparse.Namespace:
         err = "The environment variable 'SKIP_UV' is deprecated, use 'ADE_UV' or '--no-uv' instead."
         warnings.warn(err, DeprecationWarning, stacklevel=2)
 
+    if HAS_ARGCOMPLETE:
+        argcomplete.autocomplete(parser)
+
     return apply_envvars(args=args, parser=parser)
 
 

src/ansible_dev_environment/cli.py

@@ -1,3 +1,4 @@
+# PYTHON_ARGCOMPLETE_OK
 """CLI entrypoint."""
 
 from __future__ import annotations

tests/unit/test_cli.py

@@ -5,9 +5,10 @@
 from pathlib import Path
 from typing import TYPE_CHECKING
 
+import argcomplete
 import pytest
 
-from ansible_dev_environment.arg_parser import ArgumentParser, apply_envvars
+from ansible_dev_environment.arg_parser import ArgumentParser, apply_envvars, parse
 from ansible_dev_environment.cli import Cli, main
 
 
@@ -385,3 +386,53 @@ def test_env_wrong_choice(
         cli.parse_args()
     captured = capsys.readouterr()
     assert "choose from 'restrictive', 'cfg', 'none'" in captured.err
+
+
+def test_arg_complete(monkeypatch: pytest.MonkeyPatch) -> None:
+    """Test argument completion.
+
+    Args:
+        monkeypatch: Pytest fixture.
+    """
+    inited_parser = None
+    orig_apply_envvars = apply_envvars
+
+    def _apply_envvars(
+        args: list[str],
+        parser: ArgumentParser,
+    ) -> None:
+        """Apply environment variables to the argument parser.
+
+        Args:
+            args: List of arguments.
+            parser: Argument parser.
+        """
+        nonlocal inited_parser
+        inited_parser = parser
+        orig_apply_envvars(args, parser)
+
+    monkeypatch.setattr(
+        "ansible_dev_environment.arg_parser.apply_envvars",
+        _apply_envvars,
+    )
+
+    monkeypatch.setattr(
+        "sys.argv",
+        ["ade", "install"],
+    )
+    parse()
+
+    cli = "ade ins"
+    monkeypatch.setenv("_ARGCOMPLETE", "1")
+    monkeypatch.setenv("_ARGCOMPLETE_IFS", "\013")
+    monkeypatch.setenv("COMP_LINE", cli)
+    monkeypatch.setenv("COMP_POINT", str(len(cli)))
+    import io
+
+    str_io = io.StringIO()
+
+    argcomplete.autocomplete(inited_parser, exit_method=print, output_stream=str_io)  # type: ignore[arg-type]
+
+    output = str_io.getvalue()
+    assert "inspect" in output
+    assert "install" in output