Repository: huggingface/transformers
Pull request: Fix chameleon's TypeError because inputs_embeds may None

# What does this PR do?

When training Chameleon, I got the error message: "TypeError 'nonetype' object is not subscriptable". Because `inputs_embeds` may be None, I think it should check `inputs_embeds` type first before using it.

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Changed files:
filename: src/transformers/models/chameleon/modeling_chameleon.py
patch: @@ -1289,6 +1289,9 @@ def forward(
                 "You cannot specify both pixel_values and inputs_embeds at the same time, and must specify either one"
             )
 
+        if inputs_embeds is None:
+            inputs_embeds = self.embed_tokens(input_ids)
+
         if pixel_values is not None:
             image_tokens = self.get_image_tokens(pixel_values)
             special_image_mask = input_ids == self.vocabulary_mapping.image_token_id
@@ -1301,9 +1304,6 @@ def forward(
             image_tokens = image_tokens.to(input_ids.device, input_ids.dtype)
             input_ids = input_ids.masked_scatter(special_image_mask, image_tokens)
 
-        if inputs_embeds is None:
-            inputs_embeds = self.embed_tokens(input_ids)
-
         # torch.jit.trace() doesn't support cache objects in the output
         if use_cache and past_key_values is None and not torch.jit.is_tracing():
             past_key_values = DynamicCache()