pythonGH-119668: expose importlib.NamespacePath

Signed-off-by: Filipe Laíns <[email protected]>

Lib/importlib/_bootstrap_external.py

@@ -1346,7 +1346,7 @@ def get_filename(self, fullname):
         return self.path
 
 
-class _NamespacePath:
+class NamespacePath:
     """Represents a namespace package's path.  It uses the module name
     to find its parent module, and from there it looks up the parent's
     __path__.  When this changes, the module's own path is recomputed,
@@ -1405,7 +1405,7 @@ def __len__(self):
         return len(self._recalculate())
 
     def __repr__(self):
-        return f'_NamespacePath({self._path!r})'
+        return f'NamespacePath({self._path!r})'
 
     def __contains__(self, item):
         return item in self._recalculate()
@@ -1414,12 +1414,15 @@ def append(self, item):
         self._path.append(item)
 
 
+_NamespacePath = NamespacePath  # for backwards compatibility
+
+
 # This class is actually exposed publicly in a namespace package's __loader__
 # attribute, so it should be available through a non-private name.
 # https://github.com/python/cpython/issues/92054
 class NamespaceLoader:
     def __init__(self, name, path, path_finder):
-        self._path = _NamespacePath(name, path, path_finder)
+        self._path = NamespacePath(name, path, path_finder)
 
     def is_package(self, fullname):
         return True
@@ -1474,9 +1477,9 @@ def invalidate_caches():
                 del sys.path_importer_cache[name]
             elif hasattr(finder, 'invalidate_caches'):
                 finder.invalidate_caches()
-        # Also invalidate the caches of _NamespacePaths
+        # Also invalidate the caches of NamespacePaths
         # https://bugs.python.org/issue45703
-        _NamespacePath._epoch += 1
+        NamespacePath._epoch += 1
 
         from importlib.metadata import MetadataPathFinder
         MetadataPathFinder.invalidate_caches()
@@ -1562,7 +1565,7 @@ def find_spec(cls, fullname, path=None, target=None):
                 # We found at least one namespace path.  Return a spec which
                 # can create the namespace package.
                 spec.origin = None
-                spec.submodule_search_locations = _NamespacePath(fullname, namespace_path, cls._get_spec)
+                spec.submodule_search_locations = NamespacePath(fullname, namespace_path, cls._get_spec)
                 return spec
             else:
                 return None

Lib/importlib/machinery.py

@@ -14,6 +14,7 @@
 from ._bootstrap_external import ExtensionFileLoader
 from ._bootstrap_external import AppleFrameworkLoader
 from ._bootstrap_external import NamespaceLoader
+from ._bootstrap_external import NamespacePath
 
 
 def all_suffixes():