Merge branch 'main' into core_metadata

Author: pfmoore

.github/workflows/no-response.yml

@@ -53,7 +53,7 @@ Deprecations and Removals
   ``--config-settings``. (`#11859 <https://github.com/pypa/pip/issues/11859>`_)
 - Using ``--config-settings`` with projects that don't have a ``pyproject.toml`` now prints
   a deprecation warning. In the future the presence of config settings will automatically
-  enable the default build backend for legacy projects and pass the setttings to it. (`#11915 <https://github.com/pypa/pip/issues/11915>`_)
+  enable the default build backend for legacy projects and pass the settings to it. (`#11915 <https://github.com/pypa/pip/issues/11915>`_)
 - Remove ``setup.py install`` fallback when building a wheel failed for projects without
   ``pyproject.toml``. (`#8368 <https://github.com/pypa/pip/issues/8368>`_)
 - When the ``wheel`` package is not installed, pip now uses the default build backend

NEWS.rst

@@ -0,0 +1 @@
+Deprecate support for eggs for Python 3.11 or later, when the new ``importlib.metadata`` backend is used to load distribution metadata. This only affects the egg *distribution format* (with the ``.egg`` extension); distributions using the ``.egg-info`` *metadata format* (but are not actually eggs) are not affected. For more information about eggs, see `relevant section in the setuptools documentation <https://setuptools.pypa.io/en/stable/deprecated/python_eggs.html>`__.

news/11996.process.rst

@@ -0,0 +1 @@
+Fix slowness when using ``importlib.metadata`` (the default way for pip to read metadata in Python 3.11+) and there is a large overlap between already installed and to-be-installed packages.

news/12079.bugfix.rst

@@ -151,7 +151,7 @@ def _emit_egg_deprecation(location: Optional[str]) -> None:
     deprecated(
         reason=f"Loading egg at {location} is deprecated.",
         replacement="to use pip for package installation.",
-        gone_in=None,
+        gone_in="23.3",
     )
 
 
@@ -174,7 +174,7 @@ def _iter_distributions(self) -> Iterator[BaseDistribution]:
         for location in self._paths:
             yield from finder.find(location)
             for dist in finder.find_eggs(location):
-                # _emit_egg_deprecation(dist.location)  # TODO: Enable this.
+                _emit_egg_deprecation(dist.location)
                 yield dist
             # This must go last because that's how pkg_resources tie-breaks.
             yield from finder.find_linked(location)

src/pip/_internal/metadata/importlib/_envs.py

@@ -341,6 +341,7 @@ def __init__(
         self.dist = dist
         self._ireq = _make_install_req_from_dist(dist, template)
         self._factory = factory
+        self._version = None
 
         # This is just logging some messages, so we can do it eagerly.
         # The returned dist would be exactly the same as self.dist because we
@@ -376,7 +377,9 @@ def name(self) -> str:
 
     @property
     def version(self) -> CandidateVersion:
-        return self.dist.version
+        if self._version is None:
+            self._version = self.dist.version
+        return self._version
 
     @property
     def is_editable(self) -> bool: