Add DeprecationWarning for DEBUG_BYTECODE_SUFFIXES and OPTIMIZED_BYTECODE_SUFFIXES.

Co-authored-by: rashansmith <[email protected]>

Author: tomasr8

Lib/importlib/machinery.py

@@ -3,9 +3,11 @@
 from ._bootstrap import ModuleSpec
 from ._bootstrap import BuiltinImporter
 from ._bootstrap import FrozenImporter
-from ._bootstrap_external import (SOURCE_SUFFIXES, DEBUG_BYTECODE_SUFFIXES,
-                     OPTIMIZED_BYTECODE_SUFFIXES, BYTECODE_SUFFIXES,
-                     EXTENSION_SUFFIXES)
+from ._bootstrap_external import (
+    SOURCE_SUFFIXES, BYTECODE_SUFFIXES, EXTENSION_SUFFIXES,
+    DEBUG_BYTECODE_SUFFIXES as _DEBUG_BYTECODE_SUFFIXES,
+    OPTIMIZED_BYTECODE_SUFFIXES as _OPTIMIZED_BYTECODE_SUFFIXES
+)
 from ._bootstrap_external import WindowsRegistryFinder
 from ._bootstrap_external import PathFinder
 from ._bootstrap_external import FileFinder
@@ -27,3 +29,21 @@ def all_suffixes():
            'NamespaceLoader', 'OPTIMIZED_BYTECODE_SUFFIXES', 'PathFinder',
            'SOURCE_SUFFIXES', 'SourceFileLoader', 'SourcelessFileLoader',
            'WindowsRegistryFinder', 'all_suffixes']
+
+
+def __getattr__(name):
+    import warnings
+    if name == 'DEBUG_BYTECODE_SUFFIXES':
+        warnings.warn("importlib.machinery.DEBUG_BYTECODE_SUFFIXES is "
+                      "deprecated. Use importlib.machinery.BYTECODE_SUFFIXES "
+                      "instead.",
+                      DeprecationWarning, stacklevel=2)
+        return _DEBUG_BYTECODE_SUFFIXES
+    elif name == 'OPTIMIZED_BYTECODE_SUFFIXES':
+        warnings.warn("importlib.machinery.OPTIMIZED_BYTECODE_SUFFIXES is "
+                      "deprecated. Use importlib.machinery.BYTECODE_SUFFIXES "
+                      "instead.",
+                      DeprecationWarning, stacklevel=2)
+        return _OPTIMIZED_BYTECODE_SUFFIXES
+
+    raise AttributeError(f"module {__name__!r} has no attribute {name!r}")

Lib/test/test_importlib/test_api.py

@@ -492,5 +492,14 @@ def test_util(self):
         support.check__all__(self, util['Source'], extra=extra)
 
 
+class TestDeprecations(unittest.TestCase):
+    def test_machinery_deprecated_constants(self):
+        from importlib import machinery
+        for attr in ('DEBUG_BYTECODE_SUFFIXES', 'OPTIMIZED_BYTECODE_SUFFIXES'):
+            with self.subTest(attr=attr):
+                with self.assertWarns(DeprecationWarning):
+                    getattr(machinery, attr)
+
+
 if __name__ == '__main__':
     unittest.main()