Update fine-grained versioning for CPython distributions

Author: ofek

docs/plugins/environment/virtual.md

@@ -45,7 +45,7 @@ If a Python version has been chosen then each resolver will try to find an inter
 If no version has been chosen, then each resolver will try to find a version that matches the version of Python that Hatch is currently running on. If not found then each resolver will try to find the highest compatible version.
 
 !!! note
-    Some external Python paths are considered unstable and are ignored during resolution. For example, if Hatch if installed via Homebrew then `sys.executable` will be ignored because the interpreter could change or be removed at any time.
+    Some external Python paths are considered unstable and are ignored during resolution. For example, if Hatch is installed via Homebrew then `sys.executable` will be ignored because the interpreter could change or be removed at any time.
 
 !!! note
     When resolution finds a match using an [internally managed distribution](#internal-distributions) and an update is available, the latest distribution will automatically be downloaded before environment creation.

src/hatch/python/resolve.py

@@ -78,8 +78,12 @@ class CPythonStandaloneDistribution(Distribution):
     def version(self) -> Version:
         from packaging.version import Version
 
-        *_, remaining = self.source.partition('/download/')
-        version, *_ = remaining.partition('/')
+        # .../cpython-3.12.0%2B20231002-...
+        # .../cpython-3.7.9-...
+        _, _, remaining = self.source.partition('/cpython-')
+        # 3.12.0%2B20231002-...
+        # 3.7.9-...
+        version = remaining.split('%2B')[0] if '%2B' in remaining else remaining.split('-')[0]
         return Version(f'0!{version}')
 
     @cached_property

tests/python/test_resolve.py

@@ -25,7 +25,7 @@ def test_cpython_standalone(self):
         version = dist.version
 
         assert version.epoch == 0
-        assert version.base_version == '20230507'
+        assert version.base_version == '3.11.3'
 
     def test_pypy(self):
         url = 'https://downloads.python.org/pypy/pypy3.10-v7.3.12-aarch64.tar.bz2'