Merge pull request #10396 from pytest-dev/pylib-hax

vendor py.path and py.error

Author: asottile

.github/workflows/test.yml

@@ -66,7 +66,7 @@ jobs:
           - name: "windows-py37-pluggy"
             python: "3.7"
             os: windows-latest
-            tox_env: "py37-pluggymain-xdist"
+            tox_env: "py37-pluggymain-pylib-xdist"
           - name: "windows-py38"
             python: "3.8"
             os: windows-latest
@@ -93,7 +93,7 @@ jobs:
           - name: "ubuntu-py37-pluggy"
             python: "3.7"
             os: ubuntu-latest
-            tox_env: "py37-pluggymain-xdist"
+            tox_env: "py37-pluggymain-pylib-xdist"
           - name: "ubuntu-py37-freeze"
             python: "3.7"
             os: ubuntu-latest

.pre-commit-config.yaml

@@ -65,7 +65,6 @@ repos:
         args: []
         additional_dependencies:
           - iniconfig>=1.1.0
-          - py>=1.8.2
           - attrs>=19.2.0
           - packaging
           - tomli

changelog/10396.deprecation.rst

@@ -0,0 +1 @@
+pytest no longer depends on the ``py`` library.  ``pytest`` provides a vendored copy of ``py.error`` and ``py.path`` modules but will use the ``py`` library if it is installed.  If you need other ``py.*`` modules, continue to install the deprecated ``py`` library separately, otherwise it can usually be removed as a dependency.

setup.cfg

@@ -36,16 +36,17 @@ packages =
     _pytest
     _pytest._code
     _pytest._io
+    _pytest._py
     _pytest.assertion
     _pytest.config
     _pytest.mark
     pytest
+py_modules = py
 install_requires =
     attrs>=19.2.0
     iniconfig
     packaging
     pluggy>=0.12,<2.0
-    py>=1.8.2
     colorama;sys_platform=="win32"
     exceptiongroup>=1.0.0rc8;python_version<"3.11"
     importlib-metadata>=0.12;python_version<"3.8"

src/_pytest/_py/__init__.py

@@ -0,0 +1,109 @@
+"""create errno-specific classes for IO or os calls."""
+from __future__ import annotations
+
+import errno
+import os
+import sys
+from typing import Callable
+from typing import TYPE_CHECKING
+from typing import TypeVar
+
+if TYPE_CHECKING:
+    from typing_extensions import ParamSpec
+
+    P = ParamSpec("P")
+
+R = TypeVar("R")
+
+
+class Error(EnvironmentError):
+    def __repr__(self) -> str:
+        return "{}.{} {!r}: {} ".format(
+            self.__class__.__module__,
+            self.__class__.__name__,
+            self.__class__.__doc__,
+            " ".join(map(str, self.args)),
+            # repr(self.args)
+        )
+
+    def __str__(self) -> str:
+        s = "[{}]: {}".format(
+            self.__class__.__doc__,
+            " ".join(map(str, self.args)),
+        )
+        return s
+
+
+_winerrnomap = {
+    2: errno.ENOENT,
+    3: errno.ENOENT,
+    17: errno.EEXIST,
+    18: errno.EXDEV,
+    13: errno.EBUSY,  # empty cd drive, but ENOMEDIUM seems unavailiable
+    22: errno.ENOTDIR,
+    20: errno.ENOTDIR,
+    267: errno.ENOTDIR,
+    5: errno.EACCES,  # anything better?
+}
+
+
+class ErrorMaker:
+    """lazily provides Exception classes for each possible POSIX errno
+    (as defined per the 'errno' module).  All such instances
+    subclass EnvironmentError.
+    """
+
+    _errno2class: dict[int, type[Error]] = {}
+
+    def __getattr__(self, name: str) -> type[Error]:
+        if name[0] == "_":
+            raise AttributeError(name)
+        eno = getattr(errno, name)
+        cls = self._geterrnoclass(eno)
+        setattr(self, name, cls)
+        return cls
+
+    def _geterrnoclass(self, eno: int) -> type[Error]:
+        try:
+            return self._errno2class[eno]
+        except KeyError:
+            clsname = errno.errorcode.get(eno, "UnknownErrno%d" % (eno,))
+            errorcls = type(
+                clsname,
+                (Error,),
+                {"__module__": "py.error", "__doc__": os.strerror(eno)},
+            )
+            self._errno2class[eno] = errorcls
+            return errorcls
+
+    def checked_call(
+        self, func: Callable[P, R], *args: P.args, **kwargs: P.kwargs
+    ) -> R:
+        """Call a function and raise an errno-exception if applicable."""
+        __tracebackhide__ = True
+        try:
+            return func(*args, **kwargs)
+        except Error:
+            raise
+        except OSError as value:
+            if not hasattr(value, "errno"):
+                raise
+            errno = value.errno
+            if sys.platform == "win32":
+                try:
+                    cls = self._geterrnoclass(_winerrnomap[errno])
+                except KeyError:
+                    raise value
+            else:
+                # we are not on Windows, or we got a proper OSError
+                cls = self._geterrnoclass(errno)
+
+            raise cls(f"{func.__name__}{args!r}")
+
+
+_error_maker = ErrorMaker()
+checked_call = _error_maker.checked_call
+
+
+def __getattr__(attr: str) -> type[Error]:
+    return getattr(_error_maker, attr)  # type: ignore[no-any-return]

src/_pytest/_py/error.py

@@ -18,6 +18,7 @@
 from typing import Union
 
 import attr
+
 import py
 
 # fmt: off

src/_pytest/_py/path.py

@@ -0,0 +1,10 @@
+# shim for pylib going away
+# if pylib is installed this file will get skipped
+# (`py/__init__.py` has higher precedence)
+import sys
+
+import _pytest._py.error as error
+import _pytest._py.path as path
+
+sys.modules["py.error"] = error
+sys.modules["py.path"] = path

src/_pytest/compat.py

@@ -91,6 +91,12 @@ def path1(self, tmp_path_factory: TempPathFactory) -> Generator[Path, None, None
         yield path
         assert path.joinpath("samplefile").exists()
 
+    @pytest.fixture(autouse=True)
+    def preserve_sys(self):
+        with unittest.mock.patch.dict(sys.modules):
+            with unittest.mock.patch.object(sys, "path", list(sys.path)):
+                yield
+
     def setuptestfs(self, path: Path) -> None:
         # print "setting up test fs for", repr(path)
         samplefile = path / "samplefile"

src/py.py

@@ -10,7 +10,7 @@ envlist =
     py310
     py311
     pypy3
-    py37-{pexpect,xdist,unittestextras,numpy,pluggymain}
+    py37-{pexpect,xdist,unittestextras,numpy,pluggymain,pylib}
     doctesting
     plugins
     py37-freeze
@@ -54,6 +54,7 @@ deps =
     numpy: numpy>=1.19.4
     pexpect: pexpect>=4.8.0
     pluggymain: pluggy @ git+https://github.com/pytest-dev/pluggy.git
+    pylib: py>=1.8.2
     unittestextras: twisted
     unittestextras: asynctest
     xdist: pytest-xdist>=2.1.0