Skip $PATH entries we cannot check rather than dying with PermissionError (#2782)

Author: hroncok

docs/changelog/2782.bugfix.rst

@@ -0,0 +1 @@
+When a ``$PATH`` entry cannot be checked for existence, skip it instead of terminating - by :user:`hroncok`.

src/virtualenv/discovery/builtin.py

@@ -3,6 +3,7 @@
 import logging
 import os
 import sys
+from contextlib import suppress
 from pathlib import Path
 from typing import TYPE_CHECKING, Callable
 
@@ -166,8 +167,9 @@ def get_paths(env: Mapping[str, str]) -> Generator[Path, None, None]:
             path = os.defpath
     if path:
         for p in map(Path, path.split(os.pathsep)):
-            if p.exists():
-                yield p
+            with suppress(OSError):
+                if p.exists():
+                    yield p
 
 
 class LazyPathDump:

tests/unit/discovery/test_discovery.py

@@ -59,6 +59,14 @@ def test_discovery_via_path_not_found(tmp_path, monkeypatch):
     assert interpreter is None
 
 
+def test_discovery_via_path_in_nonbrowseable_directory(tmp_path, monkeypatch):
+    bad_perm = tmp_path / "bad_perm"
+    bad_perm.mkdir(mode=0o000)
+    monkeypatch.setenv("PATH", str(bad_perm / "bin"))
+    interpreter = get_interpreter(uuid4().hex, [])
+    assert interpreter is None
+
+
 def test_relative_path(session_app_data, monkeypatch):
     sys_executable = Path(PythonInfo.current_system(app_data=session_app_data).system_executable)
     cwd = sys_executable.parents[1]