experimental: uv support for Python plugins

craft_parts/plugins/base.py

@@ -136,18 +136,45 @@ class BasePythonPlugin(Plugin):
     Provides common methods for dealing with Python items.
     """
 
+    def __init__(
+        self, *, properties: PluginProperties, part_info: infos.PartInfo
+    ) -> None:
+        super().__init__(properties=properties, part_info=part_info)
+        use_uv_attr_name = f"{properties.plugin}_use_uv"
+        if not hasattr(properties, use_uv_attr_name):
+            raise AttributeError(
+                f"Plugin properties requires a {use_uv_attr_name!r} property"
+            )
+
+    @property
+    def _use_uv(self) -> bool:
+        """Whether the plugin should use uv rather than venv and pip."""
+        return getattr(self._options, f"{self._options.plugin}_use_uv", False)
+
     @override
     def get_build_snaps(self) -> set[str]:
         """Return a set of required snaps to install in the build environment."""
+        if self._use_uv:
+            return {"astral-uv"}
         return set()
 
+    @override
+    def get_pull_commands(self) -> list[str]:
+        commands = super().get_pull_commands()
+        if self._use_uv:
+            commands.append("snap alias astral-uv.uv uv || true")
+        return commands
+
     @override
     def get_build_packages(self) -> set[str]:
         """Return a set of required packages to install in the build environment.
 
         Child classes that need to override this should extend the returned set.
         """
-        return {"findutils", "python3-dev", "python3-venv"}
+        packages = {"findutils", "python3-dev"}
+        if not self._use_uv:
+            packages.add("python3-venv")
+        return packages
 
     @override
     def get_build_environment(self) -> dict[str, str]:
@@ -178,8 +205,18 @@ def _get_venv_directory(self) -> pathlib.Path:
     def _get_create_venv_commands(self) -> list[str]:
         """Get the commands for setting up the virtual environment."""
         venv_dir = self._part_info.part_install_dir
+        venv_commands = (
+            [
+                f'uv venv ${{PARTS_PYTHON_VENV_ARGS}} "{venv_dir}"',
+                f'export UV_PYTHON="{venv_dir}/bin/${{PARTS_PYTHON_INTERPRETER}}"',
+            ]
+            if self._use_uv
+            else [
+                f'"${{PARTS_PYTHON_INTERPRETER}}" -m venv ${{PARTS_PYTHON_VENV_ARGS}} "{venv_dir}"'
+            ]
+        )
         return [
-            f'"${{PARTS_PYTHON_INTERPRETER}}" -m venv ${{PARTS_PYTHON_VENV_ARGS}} "{venv_dir}"',
+            *venv_commands,
             f'PARTS_PYTHON_VENV_INTERP_PATH="{venv_dir}/bin/${{PARTS_PYTHON_INTERPRETER}}"',
         ]
 
@@ -286,6 +323,8 @@ def _get_script_interpreter(self) -> str:
 
     def _get_pip(self) -> str:
         """Get the pip command to use."""
+        if self._use_uv:
+            return "uv pip"
         return f"{self._part_info.part_install_dir}/bin/pip"
 
     @abc.abstractmethod

craft_parts/plugins/poetry_plugin.py

@@ -41,6 +41,7 @@ class PoetryPluginProperties(PluginProperties, frozen=True):
         title="Optional dependency groups",
         description="optional dependency groups to include when installing.",
     )
+    poetry_use_uv: bool = False
 
     # part properties required by the plugin
     source: str  # pyright: ignore[reportGeneralTypeIssues]

craft_parts/plugins/python_plugin.py

@@ -31,6 +31,7 @@ class PythonPluginProperties(PluginProperties, frozen=True):
     python_requirements: list[str] = []
     python_constraints: list[str] = []
     python_packages: list[str] = ["pip", "setuptools", "wheel"]
+    python_use_uv: bool = False
 
     # part properties required by the plugin
     source: str  # pyright: ignore[reportGeneralTypeIssues]

pyproject.toml

@@ -145,6 +145,16 @@ lint.ignore = [
 [tool.ruff.lint.flake8-annotations]
 allow-star-arg-any = true
 
+[tool.ruff.lint.pydocstyle]
+ignore-decorators = [  # Functions with these decorators don't have to have docstrings.
+    "typing.overload",  # Default configuration
+    # The next four are all variations on override, so child classes don't have to repeat parent classes' docstrings.
+    "overrides.override",
+    "overrides.overrides",
+    "typing.override",
+    "typing_extensions.override",
+]
+
 [tool.ruff.lint.pylint]
 max-args = 8
 max-branches = 16

tests/integration/plugins/test_poetry.py

@@ -36,14 +36,23 @@ def teardown_module():
     plugins.unregister_all()
 
 
+@pytest.fixture(params=[False, True])
+def use_uv(request):
+    return request.param
+
+
 @pytest.fixture(params=["test_poetry"])
 def source_directory(request):
     return pathlib.Path(__file__).parent / request.param
 
 
 @pytest.fixture
-def poetry_part(source_directory):
-    return {"source": str(source_directory), "plugin": "poetry"}
+def poetry_part(source_directory, use_uv):
+    return {
+        "source": str(source_directory),
+        "plugin": "poetry",
+        "poetry-use-uv": use_uv,
+    }
 
 
 @pytest.fixture
@@ -201,13 +210,19 @@ def _get_script_interpreter(self) -> str:
     with lf.action_executor() as ctx:
         ctx.execute(actions)
 
-    primed_script = pathlib.Path(lf.project_info.prime_dir, "bin/pip")
+    primed_script = pathlib.Path(lf.project_info.prime_dir, "bin/mytest")
     assert primed_script.open().readline().rstrip() == "#!/my/script/interpreter"
 
 
-def test_find_payload_python_bad_version(new_dir, partitions, parts_dict, poetry_part):
+def test_find_payload_python_bad_version(
+    new_dir, partitions, parts_dict, poetry_part, use_uv
+):
     """Test that the build fails if a payload interpreter is needed but it's the
     wrong Python version."""
+    if use_uv:
+        poetry_part["build-environment"] = [
+            {"PARTS_PYTHON_VENV_ARGS": "--allow-existing"}
+        ]
     poetry_part["override-build"] = textwrap.dedent(
         f"""\
         # Put a binary called "python3.3" in the payload
@@ -225,8 +240,7 @@ def _get_system_python_interpreter(self) -> str | None:
 
     plugins.register({"poetry": MyPoetryPlugin})
 
-    real_python = pathlib.Path(sys.executable).resolve()
-    real_basename = real_python.name
+    pathlib.Path(sys.executable).resolve()
 
     lf = LifecycleManager(
         parts_dict,
@@ -243,18 +257,33 @@ def _get_system_python_interpreter(self) -> str | None:
 
     output = out.read_text()
     expected_text = textwrap.dedent(
-        f"""\
-        Looking for a Python interpreter called "{real_basename}" in the payload...
+        """\
         Python interpreter not found in payload.
         No suitable Python interpreter found, giving up.
         """
     )
     assert expected_text in output
 
 
-def test_find_payload_python_good_version(new_dir, partitions, parts_dict, poetry_part):
+def test_find_payload_python_good_version(
+    new_dir, partitions, parts_dict, poetry_part, use_uv
+):
     """Test that the build succeeds if a payload interpreter is needed, and it's
     the right Python version."""
+    if use_uv:
+        # uv can get multiple Python versions - ensure we're using the same version.
+        python_version_str = ".".join(str(i) for i in sys.version_info[:3])
+        poetry_part["build-environment"] = [
+            {
+                "PARTS_PYTHON_VENV_ARGS": " ".join(
+                    [
+                        "--allow-existing",
+                        f"--python={python_version_str}",
+                        "--python-preference=only-system",
+                    ]
+                )
+            }
+        ]
 
     real_python = pathlib.Path(sys.executable).resolve()
     real_basename = real_python.name
@@ -284,9 +313,5 @@ def test_find_payload_python_good_version(new_dir, partitions, parts_dict, poetr
 
     output = out.read_text()
     payload_python = (install_dir / f"usr/bin/{real_basename}").resolve()
-    expected_text = textwrap.dedent(
-        f"""\
-        Found interpreter in payload: "{payload_python}"
-        """
-    )
+    expected_text = f'Found interpreter in payload: "{payload_python}"'
     assert expected_text in output

tests/integration/plugins/test_python.py

@@ -34,7 +34,12 @@ def teardown_module():
     plugins.unregister_all()
 
 
-def test_python_plugin(new_dir, partitions):
+@pytest.fixture(params=[False, True])
+def use_uv(request):
+    return request.param
+
+
+def test_python_plugin(new_dir, partitions, use_uv):
     """Prime a simple python source."""
     source_location = Path(__file__).parent / "test_python"
 
@@ -44,6 +49,7 @@ def test_python_plugin(new_dir, partitions):
           foo:
             plugin: python
             source: {source_location}
+            python-use-uv: {use_uv}
         """
     )
     parts = yaml.safe_load(parts_yaml)
@@ -61,7 +67,7 @@ def test_python_plugin(new_dir, partitions):
     assert primed_script.open().readline().rstrip() == "#!/usr/bin/env python3"
 
 
-def test_python_plugin_with_pyproject_toml(new_dir, partitions):
+def test_python_plugin_with_pyproject_toml(new_dir, partitions, use_uv):
     """Prime a simple python source."""
     source_location = Path(__file__).parent / "test_python_pyproject_toml"
 
@@ -71,6 +77,7 @@ def test_python_plugin_with_pyproject_toml(new_dir, partitions):
           foo:
             plugin: python
             source: {source_location}
+            python-use-uv: {use_uv}
         """
     )
     parts = yaml.safe_load(parts_yaml)
@@ -91,14 +98,15 @@ def test_python_plugin_with_pyproject_toml(new_dir, partitions):
     assert primed_script.open().readline().rstrip() == "#!/usr/bin/env python3"
 
 
-def test_python_plugin_symlink(new_dir, partitions):
+def test_python_plugin_symlink(new_dir, partitions, use_uv):
     """Run in the standard scenario with no overrides."""
     parts_yaml = textwrap.dedent(
-        """\
+        f"""\
         parts:
           foo:
             plugin: python
             source: .
+            python-use-uv: {use_uv}
         """
     )
     parts = yaml.safe_load(parts_yaml)
@@ -120,7 +128,7 @@ def test_python_plugin_symlink(new_dir, partitions):
     assert os.path.basename(python_link).startswith("python3")
 
 
-def test_python_plugin_override_get_system_interpreter(new_dir, partitions):
+def test_python_plugin_override_get_system_interpreter(new_dir, partitions, use_uv):
     """Override the system interpreter, link should use it."""
 
     class MyPythonPlugin(craft_parts.plugins.plugins.PythonPlugin):
@@ -131,11 +139,12 @@ def _get_system_python_interpreter(self) -> str | None:
     plugins.register({"python": MyPythonPlugin})
 
     parts_yaml = textwrap.dedent(
-        """\
+        f"""\
         parts:
           foo:
             plugin: python
             source: .
+            python-use-uv: {use_uv}
         """
     )
     parts = yaml.safe_load(parts_yaml)
@@ -155,7 +164,7 @@ def _get_system_python_interpreter(self) -> str | None:
 
 @pytest.mark.parametrize("remove_symlinks", [(True), (False)])
 def test_python_plugin_no_system_interpreter(
-    new_dir, partitions, remove_symlinks: bool  # noqa: FBT001
+    new_dir, partitions, use_uv, remove_symlinks: bool  # noqa: FBT001
 ):
     """Check that the build fails if a payload interpreter is needed but not found."""
 
@@ -173,11 +182,12 @@ def _should_remove_symlinks(self) -> bool:
     plugins.register({"python": MyPythonPlugin})
 
     parts_yaml = textwrap.dedent(
-        """\
+        f"""\
         parts:
           foo:
             plugin: python
             source: .
+            python-use-uv: {use_uv}
         """
     )
     parts = yaml.safe_load(parts_yaml)
@@ -191,7 +201,7 @@ def _should_remove_symlinks(self) -> bool:
         ctx.execute(actions)
 
 
-def test_python_plugin_remove_symlinks(new_dir, partitions):
+def test_python_plugin_remove_symlinks(new_dir, partitions, use_uv):
     """Override symlink removal."""
 
     class MyPythonPlugin(craft_parts.plugins.plugins.PythonPlugin):
@@ -223,7 +233,7 @@ def _should_remove_symlinks(self) -> bool:
     assert python_link.exists() is False
 
 
-def test_python_plugin_fix_shebangs(new_dir, partitions):
+def test_python_plugin_fix_shebangs(new_dir, partitions, use_uv):
     """Check if shebangs are properly fixed in scripts."""
     parts_yaml = textwrap.dedent(
         """\
@@ -247,7 +257,7 @@ def test_python_plugin_fix_shebangs(new_dir, partitions):
     assert primed_script.open().readline().rstrip() == "#!/usr/bin/env python3"
 
 
-def test_python_plugin_override_shebangs(new_dir, partitions):
+def test_python_plugin_override_shebangs(new_dir, partitions, use_uv):
     """Override what we want in script shebang lines."""
 
     class MyPythonPlugin(craft_parts.plugins.plugins.PythonPlugin):
@@ -294,7 +304,7 @@ def _get_script_interpreter(self) -> str:
 """
 
 
-def test_find_payload_python_bad_version(new_dir, partitions):
+def test_find_payload_python_bad_version(new_dir, partitions, use_uv):
     """Test that the build fails if a payload interpreter is needed but it's the
     wrong Python version."""
 
@@ -337,7 +347,7 @@ def _get_system_python_interpreter(self) -> str | None:
     assert expected_text in output
 
 
-def test_find_payload_python_good_version(new_dir, partitions):
+def test_find_payload_python_good_version(new_dir, partitions, use_uv):
     """Test that the build succeeds if a payload interpreter is needed, and it's
     the right Python version."""