[BugFix] Pass type directly during reduction

ghstack-source-id: 9ca5bf2
Pull Request resolved: #1223

Author: Vincent Moens

tensordict/_lazy.py

@@ -1992,11 +1992,14 @@ def _apply_nest(
         if all(r is None for r in results) and filter_empty in (None, True):
             return
         if not inplace:
-            out = type(self)(
-                *results,
-                stack_dim=self.stack_dim,
-                stack_dim_name=self._td_dim_name,
-            )
+            if results:
+                out = type(self)(
+                    *results,
+                    stack_dim=self.stack_dim,
+                    stack_dim_name=self._td_dim_name,
+                )
+            else:
+                out = None
         else:
             out = self
         if names is not NO_DEFAULT:

tensordict/_reductions.py

@@ -11,12 +11,14 @@
 from tensordict._lazy import LazyStackedTensorDict
 from tensordict._td import TensorDict
 
-from tensordict.tensorclass import NonTensorData
-from tensordict.utils import _STRDTYPE2DTYPE
+from tensordict.tensorclass import NonTensorData, NonTensorStack
+from tensordict.utils import _is_tensorclass, _STRDTYPE2DTYPE
 
 CLS_MAP = {
     "TensorDict": TensorDict,
     "LazyStackedTensorDict": LazyStackedTensorDict,
+    "NonTensorData": NonTensorData,
+    "NonTensorStack": NonTensorStack,
 }
 
 
@@ -57,7 +59,9 @@ def from_metadata(metadata=metadata_dict, prefix=None):
             d[k] = from_metadata(
                 v, prefix=prefix + (k,) if prefix is not None else (k,)
             )
-        result = CLS_MAP[cls]._from_dict_validated(d, **cls_metadata)
+        if isinstance(cls, str):
+            cls = CLS_MAP[cls]
+        result = cls._from_dict_validated(d, **cls_metadata)
         if is_locked:
             result.lock_()
         # if is_shared:
@@ -121,10 +125,15 @@ def from_metadata(metadata=metadata, prefix=None):
             d[k] = from_metadata(
                 v, prefix=prefix + (k,) if prefix is not None else (k,)
             )
-        result = CLS_MAP[cls]._from_dict_validated(d, **cls_metadata)
+        if isinstance(cls, str):
+            cls = CLS_MAP[cls]
+        result = cls._from_dict_validated(d, **cls_metadata)
         if is_locked:
             result = result.lock_()
-        result._consolidated = consolidated
+        if _is_tensorclass(cls):
+            result._tensordict._consolidated = consolidated
+        else:
+            result._consolidated = consolidated
         return result
 
     return from_metadata()

tensordict/base.py

@@ -4994,7 +4994,7 @@ def _reduce_vals_and_metadata(self, *, dtype=NO_DEFAULT, requires_metadata):
         if requires_metadata:
             # metadata is nested
             metadata_dict = {
-                "cls": type(self).__name__,
+                "cls": type(self),
                 "non_tensors": {},
                 "leaves": {},
                 "cls_metadata": self._reduce_get_metadata(),
@@ -5055,7 +5055,7 @@ def assign(
                 metadata_dict_key = None
                 if requires_metadata:
                     metadata_dict_key = metadata_dict[key] = {
-                        "cls": cls.__name__,
+                        "cls": cls,
                         "non_tensors": {},
                         "leaves": {},
                         "cls_metadata": value._reduce_get_metadata(),