fix a regression in `is_safetensors_compatible` (#9234)

fix

src/diffusers/pipelines/pipeline_loading_utils.py

@@ -89,7 +89,7 @@ for library in LOADABLE_CLASSES:
     ALL_IMPORTABLE_CLASSES.update(LOADABLE_CLASSES[library])
 
 
-def is_safetensors_compatible(filenames, passed_components=None) -> bool:
+def is_safetensors_compatible(filenames, passed_components=None, folder_names=None) -> bool:
     """
     Checking for safetensors compatibility:
     - The model is safetensors compatible only if there is a safetensors file for each model component present in
@@ -101,6 +101,8 @@ def is_safetensors_compatible(filenames, passed_components=None) -> bool:
       extension is replaced with ".safetensors"
     """
     passed_components = passed_components or []
+    if folder_names is not None:
+        filenames = {f for f in filenames if os.path.split(f)[0] in folder_names}
 
     # extract all components of the pipeline and their associated files
     components = {}

src/diffusers/pipelines/pipeline_utils.py

@@ -1416,14 +1416,18 @@ class DiffusionPipeline(ConfigMixin, PushToHubMixin):
             if (
                 use_safetensors
                 and not allow_pickle
-                and not is_safetensors_compatible(model_filenames, passed_components=passed_components)
+                and not is_safetensors_compatible(
+                    model_filenames, passed_components=passed_components, folder_names=model_folder_names
+                )
             ):
                 raise EnvironmentError(
                     f"Could not find the necessary `safetensors` weights in {model_filenames} (variant={variant})"
                 )
             if from_flax:
                 ignore_patterns = ["*.bin", "*.safetensors", "*.onnx", "*.pb"]
-            elif use_safetensors and is_safetensors_compatible(model_filenames, passed_components=passed_components):
+            elif use_safetensors and is_safetensors_compatible(
+                model_filenames, passed_components=passed_components, folder_names=model_folder_names
+            ):
                 ignore_patterns = ["*.bin", "*.msgpack"]
 
                 use_onnx = use_onnx if use_onnx is not None else pipeline_class._is_onnx

tests/pipelines/test_pipeline_utils.py

@@ -116,6 +116,30 @@ class IsSafetensorsCompatibleTests(unittest.TestCase):
         ]
         self.assertFalse(is_safetensors_compatible(filenames))
 
+    def test_transformer_model_is_compatible_variant_extra_folder(self):
+        filenames = [
+            "safety_checker/pytorch_model.fp16.bin",
+            "safety_checker/model.fp16.safetensors",
+            "vae/diffusion_pytorch_model.fp16.bin",
+            "vae/diffusion_pytorch_model.fp16.safetensors",
+            "text_encoder/pytorch_model.fp16.bin",
+            "unet/diffusion_pytorch_model.fp16.bin",
+            "unet/diffusion_pytorch_model.fp16.safetensors",
+        ]
+        self.assertTrue(is_safetensors_compatible(filenames, folder_names={"vae", "unet"}))
+
+    def test_transformer_model_is_not_compatible_variant_extra_folder(self):
+        filenames = [
+            "safety_checker/pytorch_model.fp16.bin",
+            "safety_checker/model.fp16.safetensors",
+            "vae/diffusion_pytorch_model.fp16.bin",
+            "vae/diffusion_pytorch_model.fp16.safetensors",
+            "text_encoder/pytorch_model.fp16.bin",
+            "unet/diffusion_pytorch_model.fp16.bin",
+            "unet/diffusion_pytorch_model.fp16.safetensors",
+        ]
+        self.assertFalse(is_safetensors_compatible(filenames, folder_names={"text_encoder"}))
+
     def test_transformers_is_compatible_sharded(self):
         filenames = [
             "text_encoder/pytorch_model.bin",