Keep Python 2 compatibility and allow escape prepare

Signed-off-by: Bernát Gábor <[email protected]>

.pre-commit-config.yaml

@@ -17,8 +17,6 @@ repos:
       - id: pyupgrade
         args: ["--py37-plus"]
         exclude: "^(src/pyproject_api/_backend.py|tests/demo_pkg_inline/build.py)$"
-      - id: pyupgrade
-        files: "^(src/pyproject_api/_backend.py|tests/demo_pkg_inline/build.py)$"
   - repo: https://github.com/PyCQA/isort
     rev: 5.10.1
     hooks:

docs/changelog.rst

@@ -1,6 +1,11 @@
 Release History
 ===============
 
+v1.2.1 - (2022-12-04)
+---------------------
+- Fix Python 2 incompatibility on the backend
+- Allow skipping prepare metadata for the full build by returning None as basename
+
 v1.2.0 - (2022-12-04)
 ---------------------
 - Expose which optional hooks are present or missing via :meth:`pyproject_api.Frontend.optional_hooks`

pyproject.toml

@@ -13,25 +13,18 @@ urls.Homepage = "http://pyproject_api.readthedocs.org"
 urls.Source = "https://github.com/tox-dev/pyproject-api"
 urls.Tracker = "https://github.com/tox-dev/pyproject-api/issues"
 authors = [{ name = "Bernát Gábor", email = "[email protected]" }]
-maintainers = [
-  { name = "Bernát Gábor", email = "[email protected]" },
-]
+maintainers = [{ name = "Bernát Gábor", email = "[email protected]" }]
 requires-python = ">=3.7"
-dependencies = [
-  "packaging>=21.3", 'tomli>=2.0.1; python_version < "3.11"',
-]
-optional-dependencies.docs = [
-  "furo>=2022.9.29",
-    "sphinx>=5.3",
-    "sphinx-autodoc-typehints>=1.19.5",
-]
+dependencies = ["packaging>=21.3", 'tomli>=2.0.1; python_version < "3.11"']
+optional-dependencies.docs = ["furo>=2022.9.29", "sphinx>=5.3", "sphinx-autodoc-typehints>=1.19.5"]
 optional-dependencies.testing = [
   "covdefaults>=2.2.2",
-    "pytest>=7.2",
-    "pytest-cov>=4",
-    "pytest-mock>=3.10",
-    'importlib-metadata>=5.1; python_version < "3.8"',
-    "wheel>=0.38.4",
+  "pytest>=7.2",
+  "pytest-cov>=4",
+  "pytest-mock>=3.10",
+  'importlib-metadata>=5.1; python_version < "3.8"',
+  "wheel>=0.38.4",
+  "virtualenv>=20.17",
 ]
 dynamic = ["version"]
 classifiers = [
@@ -86,6 +79,7 @@ line_length = 120
 python_version = "3.11"
 show_error_codes = true
 strict = true
+overrides = [{ module = ["virtualenv.*"], ignore_missing_imports = true }]
 
 [tool.pep8]
 max-line-length = "120"
@@ -96,5 +90,3 @@ max-line-length = 120
 unused-arguments-ignore-abstract-functions = true
 noqa-require-code = true
 dictionaries = ["en_US", "python", "technical", "django"]
-ignore = [
-]

src/pyproject_api/_backend.py

@@ -3,6 +3,7 @@
 Please keep this file Python 2.7 compatible.
 See https://tox.readthedocs.io/en/rewrite/development.html#code-style-guide
 """
+from __future__ import print_function
 
 import importlib
 import json

src/pyproject_api/_frontend.py

@@ -326,13 +326,14 @@ def prepare_metadata_for_build_wheel(
         :return: metadata generation result
         """
         self._check_metadata_dir(metadata_directory)
+        basename: str | None = None
         if self.optional_hooks["prepare_metadata_for_build_wheel"]:
             basename, out, err = self._send(
                 cmd="prepare_metadata_for_build_wheel",
                 metadata_directory=metadata_directory,
                 config_settings=config_settings,
             )
-        else:
+        if basename is None:
             # if backend does not provide it acquire it from the wheel
             basename, err, out = self._metadata_from_built_wheel(config_settings, metadata_directory, "build_wheel")
         if not isinstance(basename, str):
@@ -358,13 +359,14 @@ def prepare_metadata_for_build_editable(
         :return: metadata generation result
         """
         self._check_metadata_dir(metadata_directory)
+        basename = None
         if self.optional_hooks["prepare_metadata_for_build_editable"]:
             basename, out, err = self._send(
                 cmd="prepare_metadata_for_build_editable",
                 metadata_directory=metadata_directory,
                 config_settings=config_settings,
             )
-        else:
+        if basename is None:
             # if backend does not provide it acquire it from the wheel
             basename, err, out = self._metadata_from_built_wheel(config_settings, metadata_directory, "build_editable")
         if not isinstance(basename, str):

src/pyproject_api/_via_fresh_subprocess.py

@@ -50,6 +50,7 @@ def __init__(
         :param requires: seed requirements for the backend
         """
         super().__init__(root, backend_paths, backend_module, backend_obj, requires, reuse_backend=False)
+        self.executable = sys.executable
 
     @contextmanager
     def _send_msg(self, cmd: str, result_file: Path, msg: str) -> Iterator[SubprocessCmdStatus]:  # noqa: U100
@@ -58,7 +59,7 @@ def _send_msg(self, cmd: str, result_file: Path, msg: str) -> Iterator[Subproces
         if backend:
             env["PYTHONPATH"] = backend
         process = Popen(
-            args=[sys.executable] + self.backend_args,
+            args=[self.executable] + self.backend_args,
             stdout=PIPE,
             stderr=PIPE,
             stdin=PIPE,

tests/demo_pkg_inline/build.py

@@ -85,13 +85,13 @@ def get_requires_for_build_sdist(config_settings=None):  # noqa: U100
 
 if "HAS_REQUIRES_EDITABLE" in os.environ:
 
-    def get_requires_for_build_editable(config_settings=...):  # noqa: U100
+    def get_requires_for_build_editable(config_settings=None):  # noqa: U100
         return [1] if "REQUIRES_EDITABLE_BAD_RETURN" in os.environ else ["editables"]
 
 
 if "HAS_PREPARE_EDITABLE" in os.environ:
 
-    def prepare_metadata_for_build_editable(metadata_directory: str, config_settings=None) -> str:  # noqa: U100
+    def prepare_metadata_for_build_editable(metadata_directory, config_settings=None):  # noqa: U100
         dest = os.path.join(metadata_directory, dist_info)
         os.mkdir(dest)
         for arc_name, data in content.items():
@@ -104,7 +104,7 @@ def prepare_metadata_for_build_editable(metadata_directory: str, config_settings
         return dist_info
 
 
-def build_editable(wheel_directory, metadata_directory=None, config_settings=None) -> str:
+def build_editable(wheel_directory, metadata_directory=None, config_settings=None):
     if "BUILD_EDITABLE_BAD" in os.environ:
         return 1  # type: ignore # checking bad type on purpose
     return build_wheel(wheel_directory, metadata_directory, config_settings)

tests/test_fronted.py

@@ -6,6 +6,7 @@
 
 import pytest
 from packaging.requirements import Requirement
+from virtualenv import session_via_cli
 
 from pyproject_api._frontend import BackendFailed
 from pyproject_api._via_fresh_subprocess import SubprocessFrontend
@@ -306,3 +307,12 @@ def test_backend_build_editable_bad(tmp_path: Path, demo_pkg_inline: Path, monke
     assert not exc.args
     assert exc.exc_type == "TypeError"
     assert exc.exc_msg == "'build_editable' on 'build' returned 1 but expected type <class 'str'>"
+
+
+def test_can_build_on_python_2(demo_pkg_inline: Path, tmp_path: Path) -> None:
+    fronted = SubprocessFrontend(*SubprocessFrontend.create_args_from_folder(demo_pkg_inline)[:-1])
+    env = session_via_cli(["-p", "2.7", str(tmp_path / "venv")])
+    env.run()
+    fronted.executable = str(env.creator.exe)
+
+    fronted.build_sdist(tmp_path)

whitelist.txt

@@ -2,6 +2,7 @@ autoclass
 autodoc
 cfg
 delenv
+exe
 extlinks
 intersphinx
 iterdir
@@ -24,4 +25,5 @@ tomli
 tomllib
 typehints
 unbuffered
+virtualenv
 win32