gh-121604: Raise DeprecationWarnings in importlib

Lib/importlib/_abc.py

@@ -1,11 +1,16 @@
 """Subset of importlib.abc used to reduce importlib.util imports."""
 from . import _bootstrap
 import abc
+import warnings
 
 
 class Loader(metaclass=abc.ABCMeta):
 
     """Abstract base class for import loaders."""
+    def __init__(self):
+        warnings.warn(f"Loader is deprecated.",
+                DeprecationWarning, stacklevel=2)
+        super().__init__()
 
     def create_module(self, spec):
         """Return a module to initialize and into which to load.

Lib/importlib/_bootstrap_external.py

@@ -1037,6 +1037,10 @@ def path_mtime(self, path):
 
         Raises OSError when the path cannot be handled.
         """
+        _warnings.warn(
+            f"SourcelessFileLoader is deprecated.",
+            DeprecationWarning,
+            stacklevel=2)
         raise OSError
 
     def path_stats(self, path):
@@ -1272,6 +1276,13 @@ def set_data(self, path, data, *, _mode=0o666):
 class SourcelessFileLoader(FileLoader, _LoaderBasics):
 
     """Loader which handles sourceless file imports."""
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        _warnings.warn(
+            f"SourcelessFileLoader is deprecated.",
+            DeprecationWarning,
+            stacklevel=2
+        )
 
     def get_code(self, fullname):
         path = self.get_filename(fullname)

Lib/importlib/abc.py

@@ -13,6 +13,7 @@
     _frozen_importlib_external = _bootstrap_external
 from ._abc import Loader
 import abc
+import warnings
 
 
 __all__ = [
@@ -22,6 +23,11 @@
 ]
 
 
+def __getattr__(name):
+    if name in ('ResourceLoader' ):
+        warnings.warn(f"The '{name}' attribute is deprecated.",
+                      DeprecationWarning, stacklevel=2)
+
 def _register(abstract_cls, *classes):
     for cls in classes:
         abstract_cls.register(cls)
@@ -69,6 +75,8 @@ class ResourceLoader(Loader):
     This ABC represents one of the optional protocols specified by PEP 302.
 
     """
+    warnings.warn(f"The Resource Loader class is deprecated.",
+                    DeprecationWarning, stacklevel=2)
 
     @abc.abstractmethod
     def get_data(self, path):
@@ -85,6 +93,8 @@ class InspectLoader(Loader):
     This ABC represents one of the optional protocols specified by PEP 302.
 
     """
+    warnings.warn(f"The InspectLoader class is deprecated.",
+                    DeprecationWarning, stacklevel=2)
 
     def is_package(self, fullname):
         """Optional method which when implemented should return whether the
@@ -198,6 +208,9 @@ class SourceLoader(_bootstrap_external.SourceLoader, ResourceLoader, ExecutionLo
     """
 
     def path_mtime(self, path):
+        """Deprecated"""
+        warnings.warn(f"The path_mtime function is deprecated.",
+                    DeprecationWarning, stacklevel=2)
         """Return the (int) modification time for the path (str)."""
         if self.path_stats.__func__ is SourceLoader.path_stats:
             raise OSError

Lib/importlib/machinery.py

@@ -1,5 +1,5 @@
 """The machinery of importlib: finders, loaders, hooks, etc."""
-
+import warnings
 from ._bootstrap import ModuleSpec
 from ._bootstrap import BuiltinImporter
 from ._bootstrap import FrozenImporter
@@ -27,3 +27,13 @@ def all_suffixes():
            'NamespaceLoader', 'OPTIMIZED_BYTECODE_SUFFIXES', 'PathFinder',
            'SOURCE_SUFFIXES', 'SourceFileLoader', 'SourcelessFileLoader',
            'WindowsRegistryFinder', 'all_suffixes']
+
+
+def __getattr__(name):
+    if name in ('DEBUG_BYTECODE_SUFFIXES','OPTIMIZED_BYTECODE_SUFFIXES', 'WindowsRegistryFinder' ):
+        warnings.warn(f"The '{name}' module suffix is deprecated.",
+                      DeprecationWarning, stacklevel=2)
+        if name == 'DEBUG_BYTECODE_SUFFIXES':
+            return 1
+        else:
+            return 2