[Bugfix] Fix reloading of pixtral/llava configs (#36077)

* add is_composition flag to LlavaConfig

Signed-off-by: Kyle Sayers <kylesayrs@gmail.com>

* WIP: pixtral text config

Signed-off-by: Kyle Sayers <kylesayrs@gmail.com>

* fix style

Signed-off-by: Kyle Sayers <kylesayrs@gmail.com>

* add test

Signed-off-by: Kyle Sayers <kylesayrs@gmail.com>

* use is_composition for pixtral

Signed-off-by: Kyle Sayers <kylesayrs@gmail.com>

* Revert "use is_composition for pixtral"

This reverts commit a53d5f9.

* Revert "Revert "use is_composition for pixtral""

This reverts commit 3ab1c99.

---------

Signed-off-by: Kyle Sayers <kylesayrs@gmail.com>

Author: kylesayrs

src/transformers/models/llava/configuration_llava.py

@@ -76,6 +76,7 @@ class LlavaConfig(PretrainedConfig):
 
     model_type = "llava"
     sub_configs = {"text_config": AutoConfig, "vision_config": AutoConfig}
+    is_composition = True
 
     def __init__(
         self,

tests/models/llava/test_configuration_llava.py

@@ -0,0 +1,70 @@
+import tempfile
+import unittest
+
+from transformers import LlavaConfig
+
+
+class LlavaConfigTest(unittest.TestCase):
+    def test_llava_reload(self):
+        """
+        Simple test for reloading default llava configs
+        """
+        with tempfile.TemporaryDirectory() as tmp_dir:
+            config = LlavaConfig()
+            config.save_pretrained(tmp_dir)
+
+            reloaded = LlavaConfig.from_pretrained(tmp_dir)
+            assert config.to_dict() == reloaded.to_dict()
+
+    def test_pixtral_reload(self):
+        """
+        Simple test for reloading pixtral configs
+        """
+        vision_config = {
+            "model_type": "pixtral",
+            "head_dim": 64,
+            "hidden_act": "silu",
+            "image_size": 1024,
+            "is_composition": True,
+            "patch_size": 16,
+            "rope_theta": 10000.0,
+            "tie_word_embeddings": False,
+        }
+
+        text_config = {
+            "model_type": "mistral",
+            "hidden_size": 5120,
+            "head_dim": 128,
+            "num_attention_heads": 32,
+            "intermediate_size": 14336,
+            "is_composition": True,
+            "max_position_embeddings": 1024000,
+            "num_hidden_layers": 40,
+            "num_key_value_heads": 8,
+            "rms_norm_eps": 1e-05,
+            "rope_theta": 1000000000.0,
+            "sliding_window": None,
+            "vocab_size": 131072,
+        }
+
+        with tempfile.TemporaryDirectory() as tmp_dir:
+            config = LlavaConfig(vision_config=vision_config, text_config=text_config)
+            config.save_pretrained(tmp_dir)
+
+            reloaded = LlavaConfig.from_pretrained(tmp_dir)
+            assert config.to_dict() == reloaded.to_dict()
+
+    def test_arbitrary_reload(self):
+        """
+        Simple test for reloading arbirarily composed subconfigs
+        """
+        default_values = LlavaConfig().to_dict()
+        default_values["vision_config"]["model_type"] = "qwen2_vl"
+        default_values["text_config"]["model_type"] = "opt"
+
+        with tempfile.TemporaryDirectory() as tmp_dir:
+            config = LlavaConfig(**default_values)
+            config.save_pretrained(tmp_dir)
+
+            reloaded = LlavaConfig.from_pretrained(tmp_dir)
+            assert config.to_dict() == reloaded.to_dict()