fix ci

Signed-off-by: Hollow Man <hollowman@opensuse.org>

Author: HollowMan6

verl/utils/fsdp_utils.py

@@ -96,8 +96,8 @@ def _get_attr(attr_name, default_value=None):
         return None
 
     default_transformer_cls_names_to_wrap = getattr(module, "_no_split_modules", None)
-    fsdp_transformer_layer_cls_to_wrap = _get_attr(
-        "transformer_layer_cls_to_wrap", default_transformer_cls_names_to_wrap
+    fsdp_transformer_layer_cls_to_wrap = _normalize_transformer_layer_cls_to_wrap(
+        _get_attr("transformer_layer_cls_to_wrap", default_transformer_cls_names_to_wrap)
     )
     min_num_params = _get_attr("min_num_params", 0)
     auto_wrap_policy = None
@@ -143,6 +143,22 @@ def lambda_policy_fn(module):
     return auto_wrap_policy
 
 
+def _normalize_transformer_layer_cls_to_wrap(transformer_layer_cls_to_wrap):
+    """Normalize transformer layer class names to a reusable tuple."""
+    if transformer_layer_cls_to_wrap is None:
+        return None
+
+    if isinstance(transformer_layer_cls_to_wrap, str):
+        transformer_layer_cls_to_wrap = (transformer_layer_cls_to_wrap,)
+    else:
+        transformer_layer_cls_to_wrap = tuple(transformer_layer_cls_to_wrap)
+
+    if not transformer_layer_cls_to_wrap or any(layer_class is None for layer_class in transformer_layer_cls_to_wrap):
+        raise AssertionError("transformer_layer_cls_to_wrap must contain at least one non-None class name")
+
+    return transformer_layer_cls_to_wrap
+
+
 @torch.no_grad()
 def offload_fsdp_model_to_cpu(model: FSDP, empty_cache: bool = True):
     if fsdp_version(model) == 2 or fsdp_version(model) == 0:
@@ -536,15 +552,11 @@ def apply_fsdp2(model, fsdp_kwargs, config):
     assert CPUOffloadPolicy is not None, "PyTorch version >= 2.4 is required for using fully_shard API (FSDP2)"
 
     default_transformer_cls_names_to_wrap = getattr(model, "_no_split_modules", None)
-    fsdp_transformer_layer_cls_to_wrap = config.get("wrap_policy", {}).get(
-        "transformer_layer_cls_to_wrap", default_transformer_cls_names_to_wrap
+    wrap_policy = config.get("wrap_policy", {}) or {}
+    fsdp_transformer_layer_cls_to_wrap = _normalize_transformer_layer_cls_to_wrap(
+        wrap_policy.get("transformer_layer_cls_to_wrap", default_transformer_cls_names_to_wrap)
     )
 
-    if isinstance(fsdp_transformer_layer_cls_to_wrap, str):
-        fsdp_transformer_layer_cls_to_wrap = [fsdp_transformer_layer_cls_to_wrap]
-
-    assert len(fsdp_transformer_layer_cls_to_wrap) > 0 and fsdp_transformer_layer_cls_to_wrap[0] is not None
-
     modules = _select_fsdp2_wrap_targets(model, fsdp_transformer_layer_cls_to_wrap)
 
     for idx, module in enumerate(modules):