Automatically sort auto mappings (#17250)

* Automatically sort auto mappings

* Better class extraction

* Some auto class magic

* Adapt test and underlying behavior

* Remove re-used config

* Quality

tests/models/auto/test_configuration_auto.py

@@ -14,6 +14,8 @@
 # limitations under the License.
 
 import importlib
+import json
+import os
 import sys
 import tempfile
 import unittest
@@ -56,14 +58,14 @@ class AutoConfigTest(unittest.TestCase):
         self.assertIsInstance(config, RobertaConfig)
 
     def test_pattern_matching_fallback(self):
-        """
-        In cases where config.json doesn't include a model_type,
-        perform a few safety checks on the config mapping's order.
-        """
-        # no key string should be included in a later key string (typical failure case)
-        keys = list(CONFIG_MAPPING.keys())
-        for i, key in enumerate(keys):
-            self.assertFalse(any(key in later_key for later_key in keys[i + 1 :]))
+        with tempfile.TemporaryDirectory() as tmp_dir:
+            # This model name contains bert and roberta, but roberta ends up being picked.
+            folder = os.path.join(tmp_dir, "fake-roberta")
+            os.makedirs(folder, exist_ok=True)
+            with open(os.path.join(folder, "config.json"), "w") as f:
+                f.write(json.dumps({}))
+            config = AutoConfig.from_pretrained(folder)
+            self.assertEqual(type(config), RobertaConfig)
 
     def test_new_config_registration(self):
         try: