Repository: huggingface/transformers
Pull request: Fix crash when executing MambaCache sample code

# What does this PR do?

<!--
Congratulations! You've made it this far! You're not quite done yet though.

Once merged, your PR is going to appear in the release notes with the title you set, so make sure it's a great title that fully reflects the extent of your awesome contribution.

Then, please replace this with a description of the change and which issue is fixed (if applicable). Please also include relevant motivation and context. List any dependencies (if any) that are required for this change.

Once you're done, someone will review your PR shortly (see the section "Who can review?" below to tag some potential reviewers). They may suggest changes to make the code even better. If no one reviewed your PR after a week has passed, don't hesitate to post a new comment @-mentioning the same persons---sometimes notifications get lost.
-->

This PR updates the obsolete sample code of `MambaCache` that does not work.

## Before submitting
- [x] This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
- [x] Did you read the [contributor guideline](https://github.com/huggingface/transformers/blob/main/CONTRIBUTING.md#create-a-pull-request),
      Pull Request section?
- [ ] Was this discussed/approved via a Github issue or the [forum](https://discuss.huggingface.co/)? Please add a link
      to it if that's the case.
- [x] Did you make sure to update the documentation with your changes? Here are the
      [documentation guidelines](https://github.com/huggingface/transformers/tree/main/docs), and
      [here are tips on formatting docstrings](https://github.com/huggingface/transformers/tree/main/docs#writing-source-documentation).
- [x] Did you write any new necessary tests?


## Who can review?

Anyone in the community is free to review the PR once the tests have passed. Feel free to tag
members/contributors who may be interested in your PR.

<!-- Your PR will be replied to more quickly if you can figure out the right person to tag with @

 If you know how to use git blame, that is the easiest way, otherwise, here is a rough guide of **who to tag**.
 Please tag fewer than 3 people.

Models:

- text models: @ArthurZucker
- vision models: @amyeroberts, @qubvel
- speech models: @eustlb
- graph models: @clefourrier

Library:

- flax: @gante and @Rocketknight1
- generate: @zucchini-nlp (visual-language models) or @gante (all others)
- pipelines: @Rocketknight1
- tensorflow: @gante and @Rocketknight1
- tokenizers: @ArthurZucker
- trainer: @zach-huggingface, @SunMarc and @qgallouedec
- chat templates: @Rocketknight1

Integrations:

- deepspeed: HF Trainer/Accelerate: @SunMarc @zach-huggingface
- ray/raytune: @richardliaw, @amogkam
- Big Model Inference: @SunMarc
- quantization (bitsandbytes, autogpt): @SunMarc @MekkCyber

Documentation: @stevhliu

HF projects:

- accelerate: [different repo](https://github.com/huggingface/accelerate)
- datasets: [different repo](https://github.com/huggingface/datasets)
- diffusers: [different repo](https://github.com/huggingface/diffusers)
- rust tokenizers: [different repo](https://github.com/huggingface/tokenizers)

Maintained examples (not research project or legacy):

- Flax: @Rocketknight1
- PyTorch: See Models above and tag the person corresponding to the modality of the example.
- TensorFlow: @Rocketknight1

 -->


Changed files:
filename: src/transformers/models/falcon_mamba/modeling_falcon_mamba.py
patch: @@ -71,7 +71,8 @@ class FalconMambaCache:
         config (`PretrainedConfig):
             The configuration file defining the shape-related attributes required to initialize the static cache.
         max_batch_size (`int`):
-            The maximum batch size with which the model will be used. Note that a new instance must be instantiated if a smaller batch size is used.
+            The maximum batch size with which the model will be used. Note that a new instance must be instantiated if
+            a smaller batch size is used.
         dtype (`torch.dtype`, *optional*, defaults to `torch.float16`):
             The default `dtype` to use when initializing the layer.
         device (`torch.device` or `str`, *optional*):
@@ -80,18 +81,19 @@ class FalconMambaCache:
     Example:
 
         ```python
+        >>> import torch
         >>> from transformers import AutoTokenizer, FalconMambaForCausalLM, FalconMambaCache
 
-        >>> model = FalconMambaForCausalLM.from_pretrained("state-spaces/falcon_mamba-130m-hf")
-        >>> tokenizer = AutoTokenizer.from_pretrained("state-spaces/falcon_mamba-130m-hf")
+        >>> model = FalconMambaForCausalLM.from_pretrained("tiiuae/falcon-mamba-7b")
+        >>> tokenizer = AutoTokenizer.from_pretrained("tiiuae/falcon-mamba-7b")
 
         >>> inputs = tokenizer(text="My name is FalconMamba", return_tensors="pt")
 
         >>> # Prepare a cache class and pass it to model's forward
-        >>> past_key_values = FalconMambaCache(config=model.config, max_batch_size=1, device=model.device, dtype=model.dtype)
-        >>> outputs = model(**inputs, past_key_values=past_key_values, use_cache=True)
-        >>> outputs.past_key_values
-        FalconMambaCache()
+        >>> cache_params = FalconMambaCache(config=model.config, max_batch_size=1, device=model.device, dtype=model.dtype)
+        >>> cache_position = torch.arange(len(inputs["input_ids"][0]), device=model.device)  # sequence length
+        >>> outputs = model(**inputs, cache_params=cache_params, cache_position=cache_position, use_cache=True)
+        >>> outputs.cache_params
         ```
     """
 

filename: src/transformers/models/falcon_mamba/modular_falcon_mamba.py
patch: @@ -201,6 +201,39 @@ def __init__(
 
 
 class FalconMambaCache(MambaCache):
+    """
+    Cache for falcon_mamba model which does not have attention mechanism and key value states.
+
+    Arguments:
+        config (`PretrainedConfig):
+            The configuration file defining the shape-related attributes required to initialize the static cache.
+        max_batch_size (`int`):
+            The maximum batch size with which the model will be used. Note that a new instance must be instantiated if
+            a smaller batch size is used.
+        dtype (`torch.dtype`, *optional*, defaults to `torch.float16`):
+            The default `dtype` to use when initializing the layer.
+        device (`torch.device` or `str`, *optional*):
+            The device on which the cache should be initialized. Should be the same as the layer.
+
+    Example:
+
+        ```python
+        >>> import torch
+        >>> from transformers import AutoTokenizer, FalconMambaForCausalLM, FalconMambaCache
+
+        >>> model = FalconMambaForCausalLM.from_pretrained("tiiuae/falcon-mamba-7b")
+        >>> tokenizer = AutoTokenizer.from_pretrained("tiiuae/falcon-mamba-7b")
+
+        >>> inputs = tokenizer(text="My name is FalconMamba", return_tensors="pt")
+
+        >>> # Prepare a cache class and pass it to model's forward
+        >>> cache_params = FalconMambaCache(config=model.config, max_batch_size=1, device=model.device, dtype=model.dtype)
+        >>> cache_position = torch.arange(len(inputs["input_ids"][0]), device=model.device)  # sequence length
+        >>> outputs = model(**inputs, cache_params=cache_params, cache_position=cache_position, use_cache=True)
+        >>> outputs.cache_params
+        ```
+    """
+
     pass
 
 

filename: src/transformers/models/mamba/modeling_mamba.py
patch: @@ -64,7 +64,8 @@ class MambaCache:
         config (`PretrainedConfig):
             The configuration file defining the shape-related attributes required to initialize the static cache.
         max_batch_size (`int`):
-            The maximum batch size with which the model will be used. Note that a new instance must be instantiated if a smaller batch size is used.
+            The maximum batch size with which the model will be used. Note that a new instance must be instantiated if
+            a smaller batch size is used.
         dtype (`torch.dtype`, *optional*, defaults to `torch.float16`):
             The default `dtype` to use when initializing the layer.
         device (`torch.device` or `str`, *optional*):
@@ -73,6 +74,7 @@ class MambaCache:
     Example:
 
         ```python
+        >>> import torch
         >>> from transformers import AutoTokenizer, MambaForCausalLM, MambaCache
 
         >>> model = MambaForCausalLM.from_pretrained("state-spaces/mamba-130m-hf")
@@ -81,10 +83,10 @@ class MambaCache:
         >>> inputs = tokenizer(text="My name is Mamba", return_tensors="pt")
 
         >>> # Prepare a cache class and pass it to model's forward
-        >>> past_key_values = MambaCache(config=model.config, max_batch_size=1, device=model.device, dtype=model.dtype)
-        >>> outputs = model(**inputs, past_key_values=past_key_values, use_cache=True)
-        >>> outputs.past_key_values
-        MambaCache()
+        >>> cache_params = MambaCache(config=model.config, max_batch_size=1, device=model.device, dtype=model.dtype)
+        >>> cache_position = torch.arange(len(inputs["input_ids"][0]), device=model.device)  # sequence length
+        >>> outputs = model(**inputs, cache_params=cache_params, cache_position=cache_position, use_cache=True)
+        >>> outputs.cache_params
         ```
     """