Expose which optional hooks are present or missing

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

Author: gaborbernat

.pre-commit-config.yaml

@@ -1,6 +1,6 @@
 repos:
   - repo: https://github.com/pre-commit/pre-commit-hooks
-    rev: v4.3.0
+    rev: v4.4.0
     hooks:
       - id: check-ast
       - id: check-builtin-literals
@@ -12,7 +12,7 @@ repos:
       - id: end-of-file-fixer
       - id: trailing-whitespace
   - repo: https://github.com/asottile/pyupgrade
-    rev: v3.2.2
+    rev: v3.3.0
     hooks:
       - id: pyupgrade
         args: ["--py37-plus"]
@@ -43,7 +43,7 @@ repos:
       - id: tox-ini-fmt
         args: ["-p", "fix"]
   - repo: https://github.com/PyCQA/flake8
-    rev: 5.0.4
+    rev: 6.0.0
     hooks:
       - id: flake8
         additional_dependencies:
@@ -52,10 +52,11 @@ repos:
           - flake8-pytest-style==1.6
           - flake8-spellcheck==0.28
           - flake8-unused-arguments==0.0.12
-          - flake8-noqa==1.2.9
+          - flake8-noqa==1.3
           - pep8-naming==0.13.2
+          - flake8-pyproject==1.2.1
   - repo: https://github.com/pre-commit/mirrors-prettier
-    rev: "v3.0.0-alpha.4"
+    rev: "v2.7.1"
     hooks:
       - id: prettier
         additional_dependencies:

docs/changelog.rst

@@ -1,6 +1,10 @@
 Release History
 ===============
 
+v1.2.0 - (2022-12-04)
+---------------------
+- Expose which optional hooks are present or missing via :meth:`pyproject_api.Frontend.optional_hooks`
+
 v1.1.2 - (2022-10-30)
 ---------------------
 - Fix editable classes not exported at root level

docs/index.rst

@@ -14,6 +14,8 @@ Frontend
 --------
 .. autoclass:: Frontend
 
+.. autoclass:: OptionalHooks
+
 Exceptions
 ----------
 

pyproject.toml

@@ -23,15 +23,15 @@ dependencies = [
 optional-dependencies.docs = [
   "furo>=2022.9.29",
     "sphinx>=5.3",
-    "sphinx-autodoc-typehints>=1.19.4",
+    "sphinx-autodoc-typehints>=1.19.5",
 ]
 optional-dependencies.testing = [
-  "covdefaults>=2.2",
+  "covdefaults>=2.2.2",
     "pytest>=7.2",
     "pytest-cov>=4",
     "pytest-mock>=3.10",
-    'importlib-metadata>=5; python_version < "3.8"',
-    "wheel>=0.37.1",
+    'importlib-metadata>=5.1; python_version < "3.8"',
+    "wheel>=0.38.4",
 ]
 dynamic = ["version"]
 classifiers = [
@@ -86,3 +86,15 @@ line_length = 120
 python_version = "3.11"
 show_error_codes = true
 strict = true
+
+[tool.pep8]
+max-line-length = "120"
+
+[tool.flake8]
+max-complexity = 22
+max-line-length = 120
+unused-arguments-ignore-abstract-functions = true
+noqa-require-code = true
+dictionaries = ["en_US", "python", "technical", "django"]
+ignore = [
+]

src/pyproject_api/__init__.py

@@ -7,6 +7,7 @@
     Frontend,
     MetadataForBuildEditableResult,
     MetadataForBuildWheelResult,
+    OptionalHooks,
     RequiresBuildEditableResult,
     RequiresBuildSdistResult,
     RequiresBuildWheelResult,
@@ -33,4 +34,5 @@
     "WheelResult",
     "EditableResult",
     "SubprocessFrontend",
+    "OptionalHooks",
 ]

src/pyproject_api/_backend.py

@@ -36,6 +36,19 @@ def __str__(self):
     def _exit(self):
         return 0
 
+    def _optional_hooks(self):
+        return {
+            k: hasattr(self.backend, k)
+            for k in (
+                "get_requires_for_build_sdist",
+                "prepare_metadata_for_build_wheel",
+                "get_requires_for_build_wheel",
+                "build_editable",
+                "get_requires_for_build_editable",
+                "prepare_metadata_for_build_editable",
+            )
+        }
+
 
 def flush():
     sys.stderr.flush()

src/pyproject_api/_backend.pyi

@@ -11,6 +11,7 @@ class BackendProxy:
     def __call__(self, name: str, *args: Any, **kwargs: Any) -> Any: ...
     def __str__(self) -> str: ...
     def _exit(self) -> None: ...
+    def _optional_commands(self) -> dict[str, bool]: ...
 
 def run(argv: Sequence[str]) -> int: ...
 def read_line() -> bytearray: ...

src/pyproject_api/_frontend.py

@@ -15,6 +15,11 @@
 
 from pyproject_api._util import ensure_empty_dir
 
+if sys.version_info >= (3, 8):  # pragma: no cover (py38+)
+    from typing import TypedDict
+else:  # pragma: no cover (py38+)
+    from typing_extensions import TypedDict
+
 if sys.version_info >= (3, 11):  # pragma: no cover (py311+)
     import tomllib
 else:  # pragma: no cover (py311+)
@@ -24,6 +29,17 @@
 ConfigSettings = Optional[Dict[str, Any]]
 
 
+class OptionalHooks(TypedDict, total=True):
+    """A flag indicating if the backend supports the optional hook or not"""
+
+    get_requires_for_build_sdist: bool
+    prepare_metadata_for_build_wheel: bool
+    get_requires_for_build_wheel: bool
+    build_editable: bool
+    get_requires_for_build_editable: bool
+    prepare_metadata_for_build_editable: bool
+
+
 class CmdStatus(ABC):
     @property
     @abstractmethod
@@ -190,6 +206,7 @@ def __init__(
         self._backend_obj = backend_obj
         self.requires: tuple[Requirement, ...] = requires
         self._reuse_backend = reuse_backend
+        self._optional_hooks: OptionalHooks | None = None
 
     @classmethod
     def create_args_from_folder(
@@ -243,17 +260,25 @@ def backend_args(self) -> list[str]:
             result.append(self._backend_obj)
         return result
 
+    @property
+    def optional_hooks(self) -> OptionalHooks:
+        """:return: a dictionary indicating if the optional hook is supported or not"""
+        if self._optional_hooks is None:
+            result, _, __ = self._send("_optional_hooks")
+            self._optional_hooks = result
+        return self._optional_hooks
+
     def get_requires_for_build_sdist(self, config_settings: ConfigSettings | None = None) -> RequiresBuildSdistResult:
         """
         Get build requirements for a source distribution (per PEP-517).
 
         :param config_settings: run arguments
         :return: outcome
         """
-        try:
+        if self.optional_hooks["get_requires_for_build_sdist"]:
             result, out, err = self._send(cmd="get_requires_for_build_sdist", config_settings=config_settings)
-        except BackendFailed as exc:
-            result, out, err = [], exc.out, exc.err
+        else:
+            result, out, err = [], "", ""
         if not isinstance(result, list) or not all(isinstance(i, str) for i in result):
             self._unexpected_response("get_requires_for_build_sdist", result, "list of string", out, err)
         return RequiresBuildSdistResult(tuple(Requirement(r) for r in cast(List[str], result)), out, err)
@@ -265,10 +290,10 @@ def get_requires_for_build_wheel(self, config_settings: ConfigSettings | None =
         :param config_settings: run arguments
         :return: outcome
         """
-        try:
+        if self.optional_hooks["get_requires_for_build_wheel"]:
             result, out, err = self._send(cmd="get_requires_for_build_wheel", config_settings=config_settings)
-        except BackendFailed as exc:
-            result, out, err = [], exc.out, exc.err
+        else:
+            result, out, err = [], "", ""
         if not isinstance(result, list) or not all(isinstance(i, str) for i in result):
             self._unexpected_response("get_requires_for_build_wheel", result, "list of string", out, err)
         return RequiresBuildWheelResult(tuple(Requirement(r) for r in cast(List[str], result)), out, err)
@@ -282,10 +307,10 @@ def get_requires_for_build_editable(
         :param config_settings: run arguments
         :return: outcome
         """
-        try:
+        if self.optional_hooks["get_requires_for_build_editable"]:
             result, out, err = self._send(cmd="get_requires_for_build_editable", config_settings=config_settings)
-        except BackendFailed as exc:
-            result, out, err = [], exc.out, exc.err
+        else:
+            result, out, err = [], "", ""
         if not isinstance(result, list) or not all(isinstance(i, str) for i in result):
             self._unexpected_response("get_requires_for_build_editable", result, "list of string", out, err)
         return RequiresBuildEditableResult(tuple(Requirement(r) for r in cast(List[str], result)), out, err)
@@ -301,13 +326,13 @@ def prepare_metadata_for_build_wheel(
         :return: metadata generation result
         """
         self._check_metadata_dir(metadata_directory)
-        try:
+        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,
             )
-        except BackendFailed:
+        else:
             # 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):
@@ -333,13 +358,13 @@ def prepare_metadata_for_build_editable(
         :return: metadata generation result
         """
         self._check_metadata_dir(metadata_directory)
-        try:
+        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,
             )
-        except BackendFailed:
+        else:
             # 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):
@@ -481,5 +506,5 @@ def _send(self, cmd: str, **kwargs: Any) -> tuple[Any, str, str]:
 
     @abstractmethod
     @contextmanager
-    def _send_msg(self, cmd: str, result_file: Path, msg: str) -> Iterator[CmdStatus]:  # noqa: U100
+    def _send_msg(self, cmd: str, result_file: Path, msg: str) -> Iterator[CmdStatus]:
         raise NotImplementedError

tests/test_fronted.py

@@ -229,7 +229,7 @@ def test_backend_get_requires_for_build_editable_miss(demo_pkg_inline: Path, mon
     fronted = SubprocessFrontend(*SubprocessFrontend.create_args_from_folder(demo_pkg_inline)[:-1])
     result = fronted.get_requires_for_build_editable()
     assert not result.requires
-    assert " get_requires_for_build_editable " in result.out
+    assert not result.out
     assert not result.err
 
 

tox.ini

@@ -48,7 +48,7 @@ description = run type check on code base
 setenv =
     {tty:MYPY_FORCE_COLOR = 1}
 deps =
-    mypy==0.982
+    mypy==0.991
 commands =
     mypy src/pyproject_api --strict
     mypy tests --strict
@@ -67,7 +67,7 @@ skip_install = true
 deps =
     build[virtualenv]>=0.9
     check-wheel-contents>=0.4
-    twine>=4.0.1
+    twine>=4.0.2
 commands =
     python -m build -o {envtmpdir} -s -w .
     twine check --strict {envtmpdir}{/}*
@@ -82,13 +82,3 @@ extras =
 commands =
     python -m pip list --format=columns
     python -c "print(r'{envpython}')"
-
-[flake8]
-max-complexity = 22
-max-line-length = 120
-noqa-require-code = true
-dictionaries = en_US,python,technical,django
-ignore = E203, W503
-
-[pep8]
-max-line-length = 120