CacheDir.INSTALLED_WHEELS -> InstalledWheelDir.

pex/cache/dirs.py

@@ -7,6 +7,7 @@
 import os
 
 from pex.enum import Enum
+from pex.exceptions import production_assert
 from pex.typing import TYPE_CHECKING, cast
 from pex.variables import ENV, Variables
 
@@ -399,7 +400,14 @@ def create(
         if os.path.islink(wheel_dir):
             symlink_dir = os.path.dirname(wheel_dir)
             wheel_dir = os.path.realpath(wheel_dir)
-            wheel_hash = os.path.basename(os.path.dirname(wheel_dir))
+            recorded_wheel_hash = os.path.basename(os.path.dirname(wheel_dir))
+            if wheel_hash:
+                production_assert(wheel_hash == recorded_wheel_hash)
+            else:
+                wheel_hash = recorded_wheel_hash
+        elif wheel_hash is not None:
+            symlink_dir = os.path.dirname(wheel_dir)
+            wheel_dir = CacheDir.INSTALLED_WHEELS.path(wheel_hash, wheel_name, pex_root=pex_root)
 
         return cls(
             path=wheel_dir,

pex/pip/installation.py

@@ -11,7 +11,7 @@
 
 from pex import pep_427, pex_warnings, third_party
 from pex.atomic_directory import atomic_directory
-from pex.cache.dirs import CacheDir, PipPexDir
+from pex.cache.dirs import InstalledWheelDir, PipPexDir
 from pex.common import REPRODUCIBLE_BUILDS_ENV, CopyMode, pluralize, safe_mkdtemp
 from pex.dist_metadata import Requirement
 from pex.exceptions import production_assert
@@ -28,7 +28,7 @@
 from pex.result import Error, try_
 from pex.targets import LocalInterpreter, RequiresPythonError, Targets
 from pex.tracer import TRACER
-from pex.typing import TYPE_CHECKING
+from pex.typing import TYPE_CHECKING, cast
 from pex.util import CacheHelper
 from pex.variables import ENV, Variables
 from pex.venv.virtualenv import InstallationChoice, Virtualenv
@@ -208,22 +208,27 @@ def _install_wheel(wheel_path):
     #  https://github.com/pex-tool/pex/issues/2556
     wheel_hash = CacheHelper.hash(wheel_path, hasher=hashlib.sha256)
     wheel_name = os.path.basename(wheel_path)
-    destination = CacheDir.INSTALLED_WHEELS.path(wheel_hash, wheel_name)
-    with atomic_directory(destination) as atomic_dir:
+    installed_wheel_dir = InstalledWheelDir.create(wheel_name=wheel_name, install_hash=wheel_hash)
+    with atomic_directory(installed_wheel_dir) as atomic_dir:
         if not atomic_dir.is_finalized():
             installed_wheel = pep_427.install_wheel_chroot(
                 wheel_path=wheel_path, destination=atomic_dir.work_dir
             )
-            runtime_key_dir = CacheDir.INSTALLED_WHEELS.path(
-                installed_wheel.fingerprint
-                or CacheHelper.dir_hash(atomic_dir.work_dir, hasher=hashlib.sha256)
+            runtime_key_dir = InstalledWheelDir.create(
+                wheel_name=wheel_name,
+                install_hash=(
+                    installed_wheel.fingerprint
+                    or CacheHelper.dir_hash(atomic_dir.work_dir, hasher=hashlib.sha256)
+                ),
+                wheel_hash=wheel_hash,
             )
-            with atomic_directory(runtime_key_dir) as runtime_atomic_dir:
+            production_assert(runtime_key_dir.symlink_dir is not None)
+            with atomic_directory(cast(str, runtime_key_dir.symlink_dir)) as runtime_atomic_dir:
                 if not runtime_atomic_dir.is_finalized():
                     source_path = os.path.join(runtime_atomic_dir.work_dir, wheel_name)
-                    relative_target_path = os.path.relpath(destination, runtime_key_dir)
+                    relative_target_path = os.path.relpath(installed_wheel_dir, runtime_key_dir)
                     os.symlink(relative_target_path, source_path)
-    return destination
+    return installed_wheel_dir
 
 
 def _bootstrap_pip(

pex/third_party/__init__.py

@@ -24,6 +24,7 @@
 if TYPE_CHECKING:
     from typing import Container, Iterable, Iterator, List, Optional, Tuple
 
+    from pex.cache.dirs import InstalledWheelDir  # noqa
     from pex.interpreter import PythonInterpreter
 
 
@@ -628,10 +629,10 @@ def expose_installed_wheels(
     dists,  # type: Iterable[str]
     interpreter=None,  # type: Optional[PythonInterpreter]
 ):
-    # type: (...) -> Iterator[str]
+    # type: (...) -> Iterator[InstalledWheelDir]
 
     from pex.atomic_directory import atomic_directory
-    from pex.cache.dirs import CacheDir
+    from pex.cache.dirs import InstalledWheelDir
     from pex.pep_376 import InstalledWheel
 
     for path in expose(dists, interpreter=interpreter):
@@ -642,12 +643,14 @@ def expose_installed_wheels(
         install_hash = installed_wheel.fingerprint or CacheHelper.dir_hash(
             path, hasher=hashlib.sha256
         )
-        wheel_path = CacheDir.INSTALLED_WHEELS.path(install_hash, wheel_file_name)
-        with atomic_directory(wheel_path) as atomic_dir:
+        installed_wheel_dir = InstalledWheelDir.create(
+            wheel_name=wheel_file_name, install_hash=install_hash
+        )
+        with atomic_directory(installed_wheel_dir) as atomic_dir:
             if not atomic_dir.is_finalized():
                 for _src, _dst in iter_copytree(path, atomic_dir.work_dir, copy_mode=CopyMode.LINK):
                     pass
-        yield wheel_path
+        yield installed_wheel_dir
 
 
 # Implicitly install an importer for vendored code on the first import of pex.third_party.