Backwards compatibility for get_init_args (#16851)

Author: carmocca

src/pytorch_lightning/CHANGELOG.md

@@ -11,6 +11,7 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/).
 
 - Fixed DDP spawn hang on TPU Pods ([#16844](https://github.com/Lightning-AI/lightning/pull/16844))
 - Fixed edge cases in parsing device ids using NVML ([#16795](https://github.com/Lightning-AI/lightning/pull/16795))
+- Fixed backwards compatibility for `lightning.pytorch.utilities.parsing.get_init_args` ([#16851](https://github.com/Lightning-AI/lightning/pull/16851))
 
 
 ## [1.9.3] - 2023-02-21

src/pytorch_lightning/utilities/parsing.py

@@ -137,7 +137,13 @@ def _get_first_if_any(
     return n_self, n_args, n_kwargs
 
 
-def get_init_args(frame: types.FrameType) -> Tuple[Optional[Any], Dict[str, Any]]:
+def get_init_args(frame: types.FrameType) -> Dict[str, Any]:  # pragma: no-cover
+    """For backwards compatibility: #16369."""
+    _, local_args = _get_init_args(frame)
+    return local_args
+
+
+def _get_init_args(frame: types.FrameType) -> Tuple[Optional[Any], Dict[str, Any]]:
     _, _, _, local_vars = inspect.getargvalues(frame)
     if "__class__" not in local_vars:
         return None, {}
@@ -180,7 +186,7 @@ def collect_init_args(
     if not isinstance(frame.f_back, types.FrameType):
         return path_args
 
-    local_self, local_args = get_init_args(frame)
+    local_self, local_args = _get_init_args(frame)
     if "__class__" in local_vars and (not classes or isinstance(local_self, classes)):
         # recursive update
         path_args.append(local_args)

tests/tests_pytorch/utilities/test_parsing.py

@@ -18,11 +18,11 @@
 
 from pytorch_lightning import LightningDataModule, LightningModule, Trainer
 from pytorch_lightning.utilities.parsing import (
+    _get_init_args,
     AttributeDict,
     clean_namespace,
     collect_init_args,
     flatten_dict,
-    get_init_args,
     is_picklable,
     lightning_getattr,
     lightning_hasattr,
@@ -252,7 +252,7 @@ def __init__(self, anyarg, anykw=42, **kwargs):
 
         def get_init_args_wrapper(self):
             frame = inspect.currentframe().f_back
-            self.result = get_init_args(frame)
+            self.result = _get_init_args(frame)
 
     my_class = AutomaticArgsModel("test", anykw=32, otherkw=123)
     assert my_class.result == (my_class, {"anyarg": "test", "anykw": 32, "otherkw": 123})