Inheritance-based framework detection (#21784)

src/transformers/pipelines/base.py

@@ -15,6 +15,7 @@
 import collections
 import csv
 import importlib
+import inspect
 import json
 import os
 import pickle
@@ -269,7 +270,7 @@ def infer_framework_load_model(
         if isinstance(model, str):
             raise ValueError(f"Could not load model {model} with any of the following classes: {class_tuple}.")
 
-    framework = "tf" if model.__class__.__name__.startswith("TF") else "pt"
+    framework = "tf" if "keras.engine.training.Model" in str(inspect.getmro(model.__class__)) else "pt"
     return framework, model
 
 
@@ -342,7 +343,7 @@ def get_framework(model, revision: Optional[str] = None):
             except OSError:
                 model = TFAutoModel.from_pretrained(model, revision=revision)
 
-    framework = "tf" if model.__class__.__name__.startswith("TF") else "pt"
+    framework = "tf" if "keras.engine.training.Model" in str(inspect.getmro(model.__class__)) else "pt"
     return framework
 
 

src/transformers/utils/generic.py

@@ -366,13 +366,14 @@ def can_return_loss(model_class):
     Args:
         model_class (`type`): The class of the model.
     """
-    model_name = model_class.__name__
+    base_classes = str(inspect.getmro(model_class))
-    if model_name.startswith("TF"):
+
-        signature = inspect.signature(model_class.call)
+    if "keras.engine.training.Model" in base_classes:
-    elif model_name.startswith("Flax"):
+        signature = inspect.signature(model_class.call)  # TensorFlow models
-        signature = inspect.signature(model_class.__call__)
+    elif "torch.nn.modules.module.Module" in base_classes:
+        signature = inspect.signature(model_class.forward)  # PyTorch models
     else:
-        signature = inspect.signature(model_class.forward)
+        signature = inspect.signature(model_class.__call__)  # Flax models
 
     for p in signature.parameters:
         if p == "return_loss" and signature.parameters[p].default is True:
@@ -389,12 +390,15 @@ def find_labels(model_class):
         model_class (`type`): The class of the model.
     """
     model_name = model_class.__name__
-    if model_name.startswith("TF"):
+    base_classes = str(inspect.getmro(model_class))
-        signature = inspect.signature(model_class.call)
+
-    elif model_name.startswith("Flax"):
+    if "keras.engine.training.Model" in base_classes:
-        signature = inspect.signature(model_class.__call__)
+        signature = inspect.signature(model_class.call)  # TensorFlow models
+    elif "torch.nn.modules.module.Module" in base_classes:
+        signature = inspect.signature(model_class.forward)  # PyTorch models
     else:
-        signature = inspect.signature(model_class.forward)
+        signature = inspect.signature(model_class.__call__)  # Flax models
+
     if "QuestionAnswering" in model_name:
         return [p for p in signature.parameters if "label" in p or p in ("start_positions", "end_positions")]
     else:

tests/utils/test_file_utils.py

@@ -21,10 +21,20 @@ import transformers
 
 # Try to import everything from transformers to ensure every object can be loaded.
 from transformers import *  # noqa F406
-from transformers.testing_utils import DUMMY_UNKNOWN_IDENTIFIER
+from transformers.testing_utils import DUMMY_UNKNOWN_IDENTIFIER, require_flax, require_tf, require_torch
 from transformers.utils import ContextManagers, find_labels, is_flax_available, is_tf_available, is_torch_available
 
 
+if is_torch_available():
+    from transformers import BertForPreTraining, BertForQuestionAnswering, BertForSequenceClassification
+
+if is_tf_available():
+    from transformers import TFBertForPreTraining, TFBertForQuestionAnswering, TFBertForSequenceClassification
+
+if is_flax_available():
+    from transformers import FlaxBertForPreTraining, FlaxBertForQuestionAnswering, FlaxBertForSequenceClassification
+
+
 MODEL_ID = DUMMY_UNKNOWN_IDENTIFIER
 # An actual model hosted on huggingface.co
 
@@ -85,29 +95,39 @@ class GenericUtilTests(unittest.TestCase):
         # The output should be wrapped with an English and French welcome and goodbye
         self.assertEqual(mock_stdout.getvalue(), "Bonjour!\nWelcome!\nTransformers are awesome!\nBye!\nAu revoir!\n")
 
-    def test_find_labels(self):
+    @require_torch
-        if is_torch_available():
+    def test_find_labels_pt(self):
-            from transformers import BertForPreTraining, BertForQuestionAnswering, BertForSequenceClassification
-
         self.assertEqual(find_labels(BertForSequenceClassification), ["labels"])
         self.assertEqual(find_labels(BertForPreTraining), ["labels", "next_sentence_label"])
         self.assertEqual(find_labels(BertForQuestionAnswering), ["start_positions", "end_positions"])
 
-        if is_tf_available():
+        # find_labels works regardless of the class name (it detects the framework through inheritance)
-            from transformers import TFBertForPreTraining, TFBertForQuestionAnswering, TFBertForSequenceClassification
+        class DummyModel(BertForSequenceClassification):
+            pass
 
+        self.assertEqual(find_labels(DummyModel), ["labels"])
+
+    @require_tf
+    def test_find_labels_tf(self):
         self.assertEqual(find_labels(TFBertForSequenceClassification), ["labels"])
         self.assertEqual(find_labels(TFBertForPreTraining), ["labels", "next_sentence_label"])
         self.assertEqual(find_labels(TFBertForQuestionAnswering), ["start_positions", "end_positions"])
 
-        if is_flax_available():
+        # find_labels works regardless of the class name (it detects the framework through inheritance)
-            # Flax models don't have labels
+        class DummyModel(TFBertForSequenceClassification):
-            from transformers import (
+            pass
-                FlaxBertForPreTraining,
-                FlaxBertForQuestionAnswering,
-                FlaxBertForSequenceClassification,
-            )
 
+        self.assertEqual(find_labels(DummyModel), ["labels"])
+
+    @require_flax
+    def test_find_labels_flax(self):
+        # Flax models don't have labels
         self.assertEqual(find_labels(FlaxBertForSequenceClassification), [])
         self.assertEqual(find_labels(FlaxBertForPreTraining), [])
         self.assertEqual(find_labels(FlaxBertForQuestionAnswering), [])
+
+        # find_labels works regardless of the class name (it detects the framework through inheritance)
+        class DummyModel(FlaxBertForSequenceClassification):
+            pass
+
+        self.assertEqual(find_labels(DummyModel), [])