[WIP] warn when legacy versions are selected by the resolver

src/pip/_internal/commands/install.py

@@ -7,6 +7,7 @@
 from optparse import SUPPRESS_HELP, Values
 from typing import List, Optional
 
+from pip._vendor.packaging.version import LegacyVersion
 from pip._vendor.rich import print_json
 
 from pip._internal.cache import WheelCache
@@ -30,6 +31,7 @@
     check_legacy_setup_py_options,
 )
 from pip._internal.utils.compat import WINDOWS
+from pip._internal.utils.deprecation import deprecated
 from pip._internal.utils.filesystem import test_writable_dir
 from pip._internal.utils.logging import getLogger
 from pip._internal.utils.misc import (
@@ -378,6 +380,22 @@ def run(self, options: Values, args: List[str]) -> int:
                 reqs, check_supported_wheels=not options.target_dir
             )
 
+            for requirement in requirement_set.requirements_to_install:
+                version = requirement.get_dist().version
+                if isinstance(version, LegacyVersion):
+                    deprecated(
+                        reason=(
+                            f"pip has selected the non standard version {version} "
+                            f"of {requirement}. In the future this version will be "
+                            f"ignored as it isn't standard compliant."
+                        ),
+                        replacement=(
+                            "update constraints to select another version "
+                            "or contact the package author to fix the version number"
+                        ),
+                        gone_in="23.3",
+                    )
+
             if options.json_report_file:
                 report = InstallationReport(requirement_set.requirements_to_install)
                 if options.json_report_file == "-":

src/pip/_vendor/packaging/specifiers.py

@@ -263,7 +263,7 @@ def __init__(self, spec: str = "", prereleases: Optional[bool] = None) -> None:
 
     def _coerce_version(self, version: UnparsedVersion) -> LegacyVersion:
         if not isinstance(version, LegacyVersion):
-            version = LegacyVersion(str(version), silence_deprecation_warning=True)
+            version = LegacyVersion(str(version))
         return version
 
     def _compare_equal(self, prospective: LegacyVersion, spec: str) -> bool:

src/pip/_vendor/packaging/version.py

@@ -104,23 +104,15 @@ def __ne__(self, other: object) -> bool:
 
 
 class LegacyVersion(_BaseVersion):
-    def __init__(
-        self,
-        version: str,
-        silence_deprecation_warning: bool = False,
-    ) -> None:
+    def __init__(self, version: str) -> None:
         self._version = str(version)
         self._key = _legacy_cmpkey(self._version)
 
-        if not silence_deprecation_warning:
-            from pip._internal.utils.deprecation import deprecated
-
-            deprecated(
-                reason=(f"This form of version ({version}) has been deprecated."),
-                replacement="use PEP 440 compatible versions",
-                gone_in="23.3",
-                issue=12063,
-            )
+        warnings.warn(
+            "Creating a LegacyVersion has been deprecated and will be "
+            "removed in the next major release",
+            DeprecationWarning,
+        )
 
     def __str__(self) -> str:
         return self._version

tools/vendoring/patches/packaging.patch

@@ -1,16 +1,8 @@
-Surface LegacyVersion and LegacySpecifier deprecation warnings
-as pip deprecation warnings.
-
----
- src/pip/_vendor/packaging/specifiers.py | 12 +++++++-----
- src/pip/_vendor/packaging/version.py    | 19 +++++++++++++------
- 2 files changed, 20 insertions(+), 11 deletions(-)
-
 diff --git a/src/pip/_vendor/packaging/specifiers.py b/src/pip/_vendor/packaging/specifiers.py
-index 0e218a6f9f7..b0a1cee288b 100644
+index 0e218a6..e89026a 100644
 --- a/src/pip/_vendor/packaging/specifiers.py
 +++ b/src/pip/_vendor/packaging/specifiers.py
-@@ -252,15 +252,18 @@ class LegacySpecifier(_IndividualSpecifier):
+@@ -252,10 +252,13 @@ class LegacySpecifier(_IndividualSpecifier):
      def __init__(self, spec: str = "", prereleases: Optional[bool] = None) -> None:
          super().__init__(spec, prereleases)
 
@@ -28,43 +20,3 @@ index 0e218a6f9f7..b0a1cee288b 100644
          )
 
      def _coerce_version(self, version: UnparsedVersion) -> LegacyVersion:
-         if not isinstance(version, LegacyVersion):
--            version = LegacyVersion(str(version))
-+            version = LegacyVersion(str(version), silence_deprecation_warning=True)
-         return version
-
-     def _compare_equal(self, prospective: LegacyVersion, spec: str) -> bool:
-diff --git a/src/pip/_vendor/packaging/version.py b/src/pip/_vendor/packaging/version.py
-index de9a09a4ed3..cc68ed67424 100644
---- a/src/pip/_vendor/packaging/version.py
-+++ b/src/pip/_vendor/packaging/version.py
-@@ -104,15 +104,23 @@ def __ne__(self, other: object) -> bool:
-
-
- class LegacyVersion(_BaseVersion):
--    def __init__(self, version: str) -> None:
-+    def __init__(
-+        self,
-+        version: str,
-+        silence_deprecation_warning: bool = False,
-+    ) -> None:
-         self._version = str(version)
-         self._key = _legacy_cmpkey(self._version)
-
--        warnings.warn(
--            "Creating a LegacyVersion has been deprecated and will be "
--            "removed in the next major release",
--            DeprecationWarning,
--        )
-+        if not silence_deprecation_warning:
-+            from pip._internal.utils.deprecation import deprecated
-+
-+            deprecated(
-+                reason=(f"This form of version ({version}) has been deprecated."),
-+                replacement="use PEP 440 compatible versions",
-+                gone_in="23.3",
-+                issue=12063,
-+            )
-
-     def __str__(self) -> str:
-         return self._version