Add a hopefully failing test on Windows.

pyproject.toml

@@ -60,6 +60,7 @@ include = ["dev_cmd*"]
 
 [dependency-groups]
 dev = [
+    "ansicolors",
     "mypy",
     "pytest",
     "ruff",

tests/test_exec.py

@@ -0,0 +1,75 @@
+# Copyright 2025 John Sirois.
+# Licensed under the Apache License, Version 2.0 (see LICENSE).
+
+import subprocess
+from pathlib import Path, PurePath
+from textwrap import dedent
+
+import colors
+import pytest
+from pytest import MonkeyPatch
+
+
+@pytest.fixture
+def project_dir() -> PurePath:
+    return PurePath(
+        subprocess.run(
+            args=["git", "rev-parse", "--show-toplevel"],
+            cwd=PurePath(__file__).parent,
+            stdout=subprocess.PIPE,
+            text=True,
+            check=True,
+        ).stdout.strip()
+    )
+
+
+@pytest.fixture
+def pyproject_toml(tmp_path: Path, monkeypatch: MonkeyPatch) -> Path:
+    monkeypatch.chdir(tmp_path)
+    return tmp_path / "pyproject.toml"
+
+
+def test_exec_python(tmp_path: Path, pyproject_toml: Path, project_dir: PurePath) -> None:
+    script = tmp_path / "script.py"
+    script.write_text(
+        dedent(
+            """\
+            import sys
+
+            import colors
+
+
+            print(colors.cyan(" ".join(sys.argv[1:])))
+            """
+        )
+    )
+
+    pyproject_toml.write_text(
+        dedent(
+            f"""
+            [project]
+            name = "script-test"
+            version = "0.1.0"
+
+            [dependency-groups]
+            dev = [
+                "ansicolors",
+                "dev-cmd @ {project_dir}",
+            ]
+
+            [tool.dev-cmd.commands.test]
+            args = ["python", "{script}"]
+            accepts-extra-args = true
+            """
+        )
+    )
+
+    assert (
+        colors.cyan("Slartibartfast 42")
+        == subprocess.run(
+            args=["uv", "run", "dev-cmd", "test", "--", "Slartibartfast", "42"],
+            stdout=subprocess.PIPE,
+            text=True,
+            check=True,
+        ).stdout.strip()
+    )