make default python version a variable

src/packaged/__init__.py

@@ -11,6 +11,7 @@
 
 
 MAKESELF_PATH = os.path.join(os.path.dirname(__file__), "makeself.sh")
+DEFAULT_PYTHON_VERSION = "3.12"
 
 
 class SourceDirectoryNotFound(Exception):

src/packaged/cli.py

@@ -7,9 +7,13 @@
 import platform
 import sys
 
-from packaged import PythonNotAvailable, SourceDirectoryNotFound, create_package
+from packaged import (
+    DEFAULT_PYTHON_VERSION,
+    PythonNotAvailable,
+    SourceDirectoryNotFound,
+    create_package,
+)
 from packaged.config import (
-    Config,
     ConfigValidationError,
     config_file_exists,
     parse_config,
@@ -72,11 +76,11 @@ def cli(argv: list[str] | None = None) -> int:
         )
         parser.add_argument(
             "--python-version",
-            metavar="3.12",
+            metavar=DEFAULT_PYTHON_VERSION,
             help="Version of Python to package your project with.",
-            default="3.12",
+            default=DEFAULT_PYTHON_VERSION,
         )
-        args = parser.parse_args(argv, namespace=Config)
+        args = parser.parse_args(argv)
 
         (
             source_directory,

src/packaged/config.py

@@ -53,6 +53,7 @@ def parse_config(source_directory: str) -> Config:
             config_data["output_path"],
             config_data["build_command"],
             config_data["startup_command"],
+            config_data.get("python_version", "3.12"),
         )
     except KeyError as exc:
         key = exc.args[0]

tests/cli_test.py

@@ -2,18 +2,31 @@
 
 from unittest import mock
 
-from pytest import MonkeyPatch
-
+import packaged
 import packaged.cli
 
 
-def test_cli(monkeypatch: MonkeyPatch) -> None:
+def test_cli() -> None:
     """Ensures that CLI passes args to `create_package()` properly."""
     with mock.patch.object(packaged.cli, "create_package") as mocked:
         packaged.cli.cli(["./foo", "pip install foo", "python -m foo"])
 
     # source_directory is None
-    mocked.assert_called_with(None, "./foo", "pip install foo", "python -m foo")
+    mocked.assert_called_with(
+        None,
+        "./foo",
+        "pip install foo",
+        "python -m foo",
+        packaged.DEFAULT_PYTHON_VERSION,
+    )
+
+    with mock.patch.object(packaged.cli, "create_package") as mocked:
+        packaged.cli.cli(
+            ["./baz", "pip install baz", "python -m baz", "--python-version=3.10"]
+        )
+
+    # specified python version
+    mocked.assert_called_with(None, "./baz", "pip install baz", "python -m baz", "3.10")
 
     with mock.patch.object(packaged.cli, "create_package") as mocked:
         packaged.cli.cli(
@@ -31,6 +44,7 @@ def test_cli(monkeypatch: MonkeyPatch) -> None:
         "./bar",
         "pip install -rrequirements.txt",
         "python src/mypackage/cli.py",
+        packaged.DEFAULT_PYTHON_VERSION,
     )
     args = mocked.call_args[0]
     assert args[0].endswith("/mypackage")

tests/conftest.py

@@ -21,5 +21,5 @@ def pytest_sessionstart(session: pytest.Session) -> None:
 
         return
 
-    _, python_bin_path = packaged.ensure_python("3.12")
+    _, python_bin_path = packaged.ensure_python(packaged.DEFAULT_PYTHON_VERSION)
     assert os.path.isfile(python_bin_path)

tests/end_to_end/packaged_test.py

@@ -26,7 +26,7 @@ def build_package(
             output_path,
             build_command,
             startup_command,
-            python_version="3.12",
+            python_version=packaged.DEFAULT_PYTHON_VERSION,
         )
         yield
     finally: