[Flax] Add docstrings & model outputs (#11498)

* add attentions & hidden states

* add model outputs + docs

* finish docs

* finish tests

* finish impl

* del @

* finish

* finish

* correct test

* apply sylvains suggestions

* Update src/transformers/models/bert/modeling_flax_bert.py

Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>

* simplify more

Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>

src/transformers/file_utils.py

@@ -794,6 +794,17 @@ PT_CAUSAL_LM_SAMPLE = r"""
         >>> logits = outputs.logits
 """
 
+PT_SAMPLE_DOCSTRINGS = {
+    "SequenceClassification": PT_SEQUENCE_CLASSIFICATION_SAMPLE,
+    "QuestionAnswering": PT_QUESTION_ANSWERING_SAMPLE,
+    "TokenClassification": PT_TOKEN_CLASSIFICATION_SAMPLE,
+    "MultipleChoice": PT_MULTIPLE_CHOICE_SAMPLE,
+    "MaskedLM": PT_MASKED_LM_SAMPLE,
+    "LMHead": PT_CAUSAL_LM_SAMPLE,
+    "BaseModel": PT_BASE_MODEL_SAMPLE,
+}
+
+
 TF_TOKEN_CLASSIFICATION_SAMPLE = r"""
     Example::
 
@@ -915,30 +926,148 @@ TF_CAUSAL_LM_SAMPLE = r"""
         >>> logits = outputs.logits
 """
 
+TF_SAMPLE_DOCSTRINGS = {
+    "SequenceClassification": TF_SEQUENCE_CLASSIFICATION_SAMPLE,
+    "QuestionAnswering": TF_QUESTION_ANSWERING_SAMPLE,
+    "TokenClassification": TF_TOKEN_CLASSIFICATION_SAMPLE,
+    "MultipleChoice": TF_MULTIPLE_CHOICE_SAMPLE,
+    "MaskedLM": TF_MASKED_LM_SAMPLE,
+    "LMHead": TF_CAUSAL_LM_SAMPLE,
+    "BaseModel": TF_BASE_MODEL_SAMPLE,
+}
+
+
+FLAX_TOKEN_CLASSIFICATION_SAMPLE = r"""
+    Example::
+
+        >>> from transformers import {tokenizer_class}, {model_class}
+
+        >>> tokenizer = {tokenizer_class}.from_pretrained('{checkpoint}')
+        >>> model = {model_class}.from_pretrained('{checkpoint}')
+
+        >>> inputs = tokenizer("Hello, my dog is cute", return_tensors='jax')
+
+        >>> outputs = model(**inputs)
+        >>> logits = outputs.logits
+"""
+
+FLAX_QUESTION_ANSWERING_SAMPLE = r"""
+    Example::
+
+        >>> from transformers import {tokenizer_class}, {model_class}
+
+        >>> tokenizer = {tokenizer_class}.from_pretrained('{checkpoint}')
+        >>> model = {model_class}.from_pretrained('{checkpoint}')
+
+        >>> question, text = "Who was Jim Henson?", "Jim Henson was a nice puppet"
+        >>> inputs = tokenizer(question, text, return_tensors='jax')
+
+        >>> outputs = model(**inputs)
+        >>> start_scores = outputs.start_logits
+        >>> end_scores = outputs.end_logits
+"""
+
+FLAX_SEQUENCE_CLASSIFICATION_SAMPLE = r"""
+    Example::
+
+        >>> from transformers import {tokenizer_class}, {model_class}
+
+        >>> tokenizer = {tokenizer_class}.from_pretrained('{checkpoint}')
+        >>> model = {model_class}.from_pretrained('{checkpoint}')
+
+        >>> inputs = tokenizer("Hello, my dog is cute", return_tensors='jax')
+
+        >>> outputs = model(**inputs, labels=labels)
+        >>> logits = outputs.logits
+"""
+
+FLAX_MASKED_LM_SAMPLE = r"""
+    Example::
+
+        >>> from transformers import {tokenizer_class}, {model_class}
+
+        >>> tokenizer = {tokenizer_class}.from_pretrained('{checkpoint}')
+        >>> model = {model_class}.from_pretrained('{checkpoint}')
+
+        >>> inputs = tokenizer("The capital of France is {mask}.", return_tensors='jax')
+
+        >>> outputs = model(**inputs)
+        >>> logits = outputs.logits
+"""
+
+FLAX_BASE_MODEL_SAMPLE = r"""
+    Example::
+
+        >>> from transformers import {tokenizer_class}, {model_class}
+
+        >>> tokenizer = {tokenizer_class}.from_pretrained('{checkpoint}')
+        >>> model = {model_class}.from_pretrained('{checkpoint}')
+
+        >>> inputs = tokenizer("Hello, my dog is cute", return_tensors='jax')
+        >>> outputs = model(**inputs)
+
+        >>> last_hidden_states = outputs.last_hidden_state
+"""
+
+FLAX_MULTIPLE_CHOICE_SAMPLE = r"""
+    Example::
+
+        >>> from transformers import {tokenizer_class}, {model_class}
+
+        >>> tokenizer = {tokenizer_class}.from_pretrained('{checkpoint}')
+        >>> model = {model_class}.from_pretrained('{checkpoint}')
+
+        >>> prompt = "In Italy, pizza served in formal settings, such as at a restaurant, is presented unsliced."
+        >>> choice0 = "It is eaten with a fork and a knife."
+        >>> choice1 = "It is eaten while held in the hand."
+
+        >>> encoding = tokenizer([[prompt, prompt], [choice0, choice1]], return_tensors='jax', padding=True)
+        >>> outputs = model(**{{k: v[None, :] for k,v in encoding.items()}})
+
+        >>> logits = outputs.logits
+"""
+
+FLAX_SAMPLE_DOCSTRINGS = {
+    "SequenceClassification": FLAX_SEQUENCE_CLASSIFICATION_SAMPLE,
+    "QuestionAnswering": FLAX_QUESTION_ANSWERING_SAMPLE,
+    "TokenClassification": FLAX_TOKEN_CLASSIFICATION_SAMPLE,
+    "MultipleChoice": FLAX_MULTIPLE_CHOICE_SAMPLE,
+    "MaskedLM": FLAX_MASKED_LM_SAMPLE,
+    "BaseModel": FLAX_BASE_MODEL_SAMPLE,
+}
+
 
 def add_code_sample_docstrings(
-    *docstr, tokenizer_class=None, checkpoint=None, output_type=None, config_class=None, mask=None
+    *docstr, tokenizer_class=None, checkpoint=None, output_type=None, config_class=None, mask=None, model_cls=None
 ):
     def docstring_decorator(fn):
-        model_class = fn.__qualname__.split(".")[0]
+        # model_class defaults to function's class if not specified otherwise
-        is_tf_class = model_class[:2] == "TF"
+        model_class = fn.__qualname__.split(".")[0] if model_cls is None else model_cls
+
+        if model_class[:2] == "TF":
+            sample_docstrings = TF_SAMPLE_DOCSTRINGS
+        elif model_class[:4] == "Flax":
+            sample_docstrings = FLAX_SAMPLE_DOCSTRINGS
+        else:
+            sample_docstrings = PT_SAMPLE_DOCSTRINGS
+
         doc_kwargs = dict(model_class=model_class, tokenizer_class=tokenizer_class, checkpoint=checkpoint)
 
         if "SequenceClassification" in model_class:
-            code_sample = TF_SEQUENCE_CLASSIFICATION_SAMPLE if is_tf_class else PT_SEQUENCE_CLASSIFICATION_SAMPLE
+            code_sample = sample_docstrings["SequenceClassification"]
         elif "QuestionAnswering" in model_class:
-            code_sample = TF_QUESTION_ANSWERING_SAMPLE if is_tf_class else PT_QUESTION_ANSWERING_SAMPLE
+            code_sample = sample_docstrings["QuestionAnswering"]
         elif "TokenClassification" in model_class:
-            code_sample = TF_TOKEN_CLASSIFICATION_SAMPLE if is_tf_class else PT_TOKEN_CLASSIFICATION_SAMPLE
+            code_sample = sample_docstrings["TokenClassification"]
         elif "MultipleChoice" in model_class:
-            code_sample = TF_MULTIPLE_CHOICE_SAMPLE if is_tf_class else PT_MULTIPLE_CHOICE_SAMPLE
+            code_sample = sample_docstrings["MultipleChoice"]
         elif "MaskedLM" in model_class or model_class in ["FlaubertWithLMHeadModel", "XLMWithLMHeadModel"]:
             doc_kwargs["mask"] = "[MASK]" if mask is None else mask
-            code_sample = TF_MASKED_LM_SAMPLE if is_tf_class else PT_MASKED_LM_SAMPLE
+            code_sample = sample_docstrings["MaskedLM"]
         elif "LMHead" in model_class or "CausalLM" in model_class:
-            code_sample = TF_CAUSAL_LM_SAMPLE if is_tf_class else PT_CAUSAL_LM_SAMPLE
+            code_sample = sample_docstrings["LMHead"]
         elif "Model" in model_class or "Encoder" in model_class:
-            code_sample = TF_BASE_MODEL_SAMPLE if is_tf_class else PT_BASE_MODEL_SAMPLE
+            code_sample = sample_docstrings["BaseModel"]
         else:
             raise ValueError(f"Docstring can't be built for model {model_class}")
 
@@ -1462,7 +1591,10 @@ def tf_required(func):
 
 
 def is_tensor(x):
-    """Tests if ``x`` is a :obj:`torch.Tensor`, :obj:`tf.Tensor` or :obj:`np.ndarray`."""
+    """
+    Tests if ``x`` is a :obj:`torch.Tensor`, :obj:`tf.Tensor`, obj:`jaxlib.xla_extension.DeviceArray` or
+    :obj:`np.ndarray`.
+    """
     if is_torch_available():
         import torch
 
@@ -1473,6 +1605,14 @@ def is_tensor(x):
 
         if isinstance(x, tf.Tensor):
             return True
+
+    if is_flax_available():
+        import jaxlib.xla_extension as jax_xla
+        from jax.interpreters.partial_eval import DynamicJaxprTracer
+
+        if isinstance(x, (jax_xla.DeviceArray, DynamicJaxprTracer)):
+            return True
+
     return isinstance(x, np.ndarray)
 
 

src/transformers/modeling_flax_outputs.py

@@ -0,0 +1,239 @@
+# Copyright 2021 The HuggingFace Team. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from dataclasses import dataclass
+from typing import Optional, Tuple
+
+import jaxlib.xla_extension as jax_xla
+
+from .file_utils import ModelOutput
+
+
+@dataclass
+class FlaxBaseModelOutput(ModelOutput):
+    """
+    Base class for model's outputs, with potential hidden states and attentions.
+
+    Args:
+        last_hidden_state (:obj:`jax_xla.DeviceArray` of shape :obj:`(batch_size, sequence_length, hidden_size)`):
+            Sequence of hidden-states at the output of the last layer of the model.
+        hidden_states (:obj:`tuple(jax_xla.DeviceArray)`, `optional`, returned when ``output_hidden_states=True`` is passed or when ``config.output_hidden_states=True``):
+            Tuple of :obj:`jax_xla.DeviceArray` (one for the output of the embeddings + one for the output of each
+            layer) of shape :obj:`(batch_size, sequence_length, hidden_size)`.
+
+            Hidden-states of the model at the output of each layer plus the initial embedding outputs.
+        attentions (:obj:`tuple(jax_xla.DeviceArray)`, `optional`, returned when ``output_attentions=True`` is passed or when ``config.output_attentions=True``):
+            Tuple of :obj:`jax_xla.DeviceArray` (one for each layer) of shape :obj:`(batch_size, num_heads,
+            sequence_length, sequence_length)`.
+
+            Attentions weights after the attention softmax, used to compute the weighted average in the self-attention
+            heads.
+    """
+
+    last_hidden_state: jax_xla.DeviceArray = None
+    hidden_states: Optional[Tuple[jax_xla.DeviceArray]] = None
+    attentions: Optional[Tuple[jax_xla.DeviceArray]] = None
+
+
+@dataclass
+class FlaxBaseModelOutputWithPooling(ModelOutput):
+    """
+    Base class for model's outputs that also contains a pooling of the last hidden states.
+
+    Args:
+        last_hidden_state (:obj:`jax_xla.DeviceArray` of shape :obj:`(batch_size, sequence_length, hidden_size)`):
+            Sequence of hidden-states at the output of the last layer of the model.
+        pooler_output (:obj:`jax_xla.DeviceArray` of shape :obj:`(batch_size, hidden_size)`):
+            Last layer hidden-state of the first token of the sequence (classification token) further processed by a
+            Linear layer and a Tanh activation function. The Linear layer weights are trained from the next sentence
+            prediction (classification) objective during pretraining.
+        hidden_states (:obj:`tuple(jax_xla.DeviceArray)`, `optional`, returned when ``output_hidden_states=True`` is passed or when ``config.output_hidden_states=True``):
+            Tuple of :obj:`jax_xla.DeviceArray` (one for the output of the embeddings + one for the output of each
+            layer) of shape :obj:`(batch_size, sequence_length, hidden_size)`.
+
+            Hidden-states of the model at the output of each layer plus the initial embedding outputs.
+        attentions (:obj:`tuple(jax_xla.DeviceArray)`, `optional`, returned when ``output_attentions=True`` is passed or when ``config.output_attentions=True``):
+            Tuple of :obj:`jax_xla.DeviceArray` (one for each layer) of shape :obj:`(batch_size, num_heads,
+            sequence_length, sequence_length)`.
+
+            Attentions weights after the attention softmax, used to compute the weighted average in the self-attention
+            heads.
+    """
+
+    last_hidden_state: jax_xla.DeviceArray = None
+    pooler_output: jax_xla.DeviceArray = None
+    hidden_states: Optional[Tuple[jax_xla.DeviceArray]] = None
+    attentions: Optional[Tuple[jax_xla.DeviceArray]] = None
+
+
+@dataclass
+class FlaxMaskedLMOutput(ModelOutput):
+    """
+    Base class for masked language models outputs.
+
+    Args:
+        logits (:obj:`jax_xla.DeviceArray` of shape :obj:`(batch_size, sequence_length, config.vocab_size)`):
+            Prediction scores of the language modeling head (scores for each vocabulary token before SoftMax).
+        hidden_states (:obj:`tuple(jax_xla.DeviceArray)`, `optional`, returned when ``output_hidden_states=True`` is passed or when ``config.output_hidden_states=True``):
+            Tuple of :obj:`jax_xla.DeviceArray` (one for the output of the embeddings + one for the output of each
+            layer) of shape :obj:`(batch_size, sequence_length, hidden_size)`.
+
+            Hidden-states of the model at the output of each layer plus the initial embedding outputs.
+        attentions (:obj:`tuple(jax_xla.DeviceArray)`, `optional`, returned when ``output_attentions=True`` is passed or when ``config.output_attentions=True``):
+            Tuple of :obj:`jax_xla.DeviceArray` (one for each layer) of shape :obj:`(batch_size, num_heads,
+            sequence_length, sequence_length)`.
+
+            Attentions weights after the attention softmax, used to compute the weighted average in the self-attention
+            heads.
+    """
+
+    logits: jax_xla.DeviceArray = None
+    hidden_states: Optional[Tuple[jax_xla.DeviceArray]] = None
+    attentions: Optional[Tuple[jax_xla.DeviceArray]] = None
+
+
+@dataclass
+class FlaxNextSentencePredictorOutput(ModelOutput):
+    """
+    Base class for outputs of models predicting if two sentences are consecutive or not.
+
+    Args:
+        logits (:obj:`jax_xla.DeviceArray` of shape :obj:`(batch_size, 2)`):
+            Prediction scores of the next sequence prediction (classification) head (scores of True/False continuation
+            before SoftMax).
+        hidden_states (:obj:`tuple(jax_xla.DeviceArray)`, `optional`, returned when ``output_hidden_states=True`` is passed or when ``config.output_hidden_states=True``):
+            Tuple of :obj:`jax_xla.DeviceArray` (one for the output of the embeddings + one for the output of each
+            layer) of shape :obj:`(batch_size, sequence_length, hidden_size)`.
+
+            Hidden-states of the model at the output of each layer plus the initial embedding outputs.
+        attentions (:obj:`tuple(jax_xla.DeviceArray)`, `optional`, returned when ``output_attentions=True`` is passed or when ``config.output_attentions=True``):
+            Tuple of :obj:`jax_xla.DeviceArray` (one for each layer) of shape :obj:`(batch_size, num_heads,
+            sequence_length, sequence_length)`.
+
+            Attentions weights after the attention softmax, used to compute the weighted average in the self-attention
+            heads.
+    """
+
+    logits: jax_xla.DeviceArray = None
+    hidden_states: Optional[Tuple[jax_xla.DeviceArray]] = None
+    attentions: Optional[Tuple[jax_xla.DeviceArray]] = None
+
+
+@dataclass
+class FlaxSequenceClassifierOutput(ModelOutput):
+    """
+    Base class for outputs of sentence classification models.
+
+    Args:
+        logits (:obj:`jax_xla.DeviceArray` of shape :obj:`(batch_size, config.num_labels)`):
+            Classification (or regression if config.num_labels==1) scores (before SoftMax).
+        hidden_states (:obj:`tuple(jax_xla.DeviceArray)`, `optional`, returned when ``output_hidden_states=True`` is passed or when ``config.output_hidden_states=True``):
+            Tuple of :obj:`jax_xla.DeviceArray` (one for the output of the embeddings + one for the output of each
+            layer) of shape :obj:`(batch_size, sequence_length, hidden_size)`.
+
+            Hidden-states of the model at the output of each layer plus the initial embedding outputs.
+        attentions (:obj:`tuple(jax_xla.DeviceArray)`, `optional`, returned when ``output_attentions=True`` is passed or when ``config.output_attentions=True``):
+            Tuple of :obj:`jax_xla.DeviceArray` (one for each layer) of shape :obj:`(batch_size, num_heads,
+            sequence_length, sequence_length)`.
+
+            Attentions weights after the attention softmax, used to compute the weighted average in the self-attention
+            heads.
+    """
+
+    logits: jax_xla.DeviceArray = None
+    hidden_states: Optional[Tuple[jax_xla.DeviceArray]] = None
+    attentions: Optional[Tuple[jax_xla.DeviceArray]] = None
+
+
+@dataclass
+class FlaxMultipleChoiceModelOutput(ModelOutput):
+    """
+    Base class for outputs of multiple choice models.
+
+    Args:
+        logits (:obj:`jax_xla.DeviceArray` of shape :obj:`(batch_size, num_choices)`):
+            `num_choices` is the second dimension of the input tensors. (see `input_ids` above).
+
+            Classification scores (before SoftMax).
+        hidden_states (:obj:`tuple(jax_xla.DeviceArray)`, `optional`, returned when ``output_hidden_states=True`` is passed or when ``config.output_hidden_states=True``):
+            Tuple of :obj:`jax_xla.DeviceArray` (one for the output of the embeddings + one for the output of each
+            layer) of shape :obj:`(batch_size, sequence_length, hidden_size)`.
+
+            Hidden-states of the model at the output of each layer plus the initial embedding outputs.
+        attentions (:obj:`tuple(jax_xla.DeviceArray)`, `optional`, returned when ``output_attentions=True`` is passed or when ``config.output_attentions=True``):
+            Tuple of :obj:`jax_xla.DeviceArray` (one for each layer) of shape :obj:`(batch_size, num_heads,
+            sequence_length, sequence_length)`.
+
+            Attentions weights after the attention softmax, used to compute the weighted average in the self-attention
+            heads.
+    """
+
+    logits: jax_xla.DeviceArray = None
+    hidden_states: Optional[Tuple[jax_xla.DeviceArray]] = None
+    attentions: Optional[Tuple[jax_xla.DeviceArray]] = None
+
+
+@dataclass
+class FlaxTokenClassifierOutput(ModelOutput):
+    """
+    Base class for outputs of token classification models.
+
+    Args:
+        logits (:obj:`jax_xla.DeviceArray` of shape :obj:`(batch_size, sequence_length, config.num_labels)`):
+            Classification scores (before SoftMax).
+        hidden_states (:obj:`tuple(jax_xla.DeviceArray)`, `optional`, returned when ``output_hidden_states=True`` is passed or when ``config.output_hidden_states=True``):
+            Tuple of :obj:`jax_xla.DeviceArray` (one for the output of the embeddings + one for the output of each
+            layer) of shape :obj:`(batch_size, sequence_length, hidden_size)`.
+
+            Hidden-states of the model at the output of each layer plus the initial embedding outputs.
+        attentions (:obj:`tuple(jax_xla.DeviceArray)`, `optional`, returned when ``output_attentions=True`` is passed or when ``config.output_attentions=True``):
+            Tuple of :obj:`jax_xla.DeviceArray` (one for each layer) of shape :obj:`(batch_size, num_heads,
+            sequence_length, sequence_length)`.
+
+            Attentions weights after the attention softmax, used to compute the weighted average in the self-attention
+            heads.
+    """
+
+    logits: jax_xla.DeviceArray = None
+    hidden_states: Optional[Tuple[jax_xla.DeviceArray]] = None
+    attentions: Optional[Tuple[jax_xla.DeviceArray]] = None
+
+
+@dataclass
+class FlaxQuestionAnsweringModelOutput(ModelOutput):
+    """
+    Base class for outputs of question answering models.
+
+    Args:
+        start_logits (:obj:`jax_xla.DeviceArray` of shape :obj:`(batch_size, sequence_length)`):
+            Span-start scores (before SoftMax).
+        end_logits (:obj:`jax_xla.DeviceArray` of shape :obj:`(batch_size, sequence_length)`):
+            Span-end scores (before SoftMax).
+        hidden_states (:obj:`tuple(jax_xla.DeviceArray)`, `optional`, returned when ``output_hidden_states=True`` is passed or when ``config.output_hidden_states=True``):
+            Tuple of :obj:`jax_xla.DeviceArray` (one for the output of the embeddings + one for the output of each
+            layer) of shape :obj:`(batch_size, sequence_length, hidden_size)`.
+
+            Hidden-states of the model at the output of each layer plus the initial embedding outputs.
+        attentions (:obj:`tuple(jax_xla.DeviceArray)`, `optional`, returned when ``output_attentions=True`` is passed or when ``config.output_attentions=True``):
+            Tuple of :obj:`jax_xla.DeviceArray` (one for each layer) of shape :obj:`(batch_size, num_heads,
+            sequence_length, sequence_length)`.
+
+            Attentions weights after the attention softmax, used to compute the weighted average in the self-attention
+            heads.
+    """
+
+    start_logits: jax_xla.DeviceArray = None
+    end_logits: jax_xla.DeviceArray = None
+    hidden_states: Optional[Tuple[jax_xla.DeviceArray]] = None
+    attentions: Optional[Tuple[jax_xla.DeviceArray]] = None

src/transformers/modeling_flax_utils.py

@@ -32,12 +32,14 @@ from .file_utils import (
     FLAX_WEIGHTS_NAME,
     WEIGHTS_NAME,
     PushToHubMixin,
+    add_code_sample_docstrings,
     add_start_docstrings_to_model_forward,
     cached_path,
     copy_func,
     hf_bucket_url,
     is_offline_mode,
     is_remote_url,
+    replace_return_docstrings,
 )
 from .modeling_flax_pytorch_utils import load_pytorch_checkpoint_in_flax_state_dict
 from .utils import logging
@@ -432,3 +434,22 @@ def overwrite_call_docstring(model_class, docstring):
     model_class.__call__.__doc__ = None
     # set correct docstring
     model_class.__call__ = add_start_docstrings_to_model_forward(docstring)(model_class.__call__)
+
+
+def append_call_sample_docstring(model_class, tokenizer_class, checkpoint, output_type, config_class, mask=None):
+    model_class.__call__ = copy_func(model_class.__call__)
+    model_class.__call__ = add_code_sample_docstrings(
+        tokenizer_class=tokenizer_class,
+        checkpoint=checkpoint,
+        output_type=output_type,
+        config_class=config_class,
+        model_cls=model_class.__name__,
+    )(model_class.__call__)
+
+
+def append_replace_return_docstrings(model_class, output_type, config_class):
+    model_class.__call__ = copy_func(model_class.__call__)
+    model_class.__call__ = replace_return_docstrings(
+        output_type=output_type,
+        config_class=config_class,
+    )(model_class.__call__)

src/transformers/models/bert/modeling_flax_bert.py

@@ -13,30 +13,79 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from typing import Callable, Tuple
+from dataclasses import dataclass
+from typing import Callable, Optional, Tuple
 
 import numpy as np
 
 import flax.linen as nn
 import jax
 import jax.numpy as jnp
+import jaxlib.xla_extension as jax_xla
 from flax.core.frozen_dict import FrozenDict
 from flax.linen import dot_product_attention
 from jax import lax
 from jax.random import PRNGKey
 
-from ...file_utils import add_start_docstrings, add_start_docstrings_to_model_forward
+from ...file_utils import ModelOutput, add_start_docstrings, add_start_docstrings_to_model_forward
-from ...modeling_flax_utils import ACT2FN, FlaxPreTrainedModel, overwrite_call_docstring
+from ...modeling_flax_outputs import (
+    FlaxBaseModelOutput,
+    FlaxBaseModelOutputWithPooling,
+    FlaxMaskedLMOutput,
+    FlaxMultipleChoiceModelOutput,
+    FlaxNextSentencePredictorOutput,
+    FlaxQuestionAnsweringModelOutput,
+    FlaxSequenceClassifierOutput,
+    FlaxTokenClassifierOutput,
+)
+from ...modeling_flax_utils import (
+    ACT2FN,
+    FlaxPreTrainedModel,
+    append_call_sample_docstring,
+    append_replace_return_docstrings,
+    overwrite_call_docstring,
+)
 from ...utils import logging
 from .configuration_bert import BertConfig
 
 
 logger = logging.get_logger(__name__)
 
+_CHECKPOINT_FOR_DOC = "bert-base-uncased"
 _CONFIG_FOR_DOC = "BertConfig"
 _TOKENIZER_FOR_DOC = "BertTokenizer"
 
 
+@dataclass
+class FlaxBertForPreTrainingOutput(ModelOutput):
+    """
+    Output type of :class:`~transformers.BertForPreTraining`.
+
+    Args:
+        prediction_logits (:obj:`jax_xla.DeviceArray` of shape :obj:`(batch_size, sequence_length, config.vocab_size)`):
+            Prediction scores of the language modeling head (scores for each vocabulary token before SoftMax).
+        seq_relationship_logits (:obj:`jax_xla.DeviceArray` of shape :obj:`(batch_size, 2)`):
+            Prediction scores of the next sequence prediction (classification) head (scores of True/False continuation
+            before SoftMax).
+        hidden_states (:obj:`tuple(jax_xla.DeviceArray)`, `optional`, returned when ``output_hidden_states=True`` is passed or when ``config.output_hidden_states=True``):
+            Tuple of :obj:`jax_xla.DeviceArray` (one for the output of the embeddings + one for the output of each
+            layer) of shape :obj:`(batch_size, sequence_length, hidden_size)`.
+
+            Hidden-states of the model at the output of each layer plus the initial embedding outputs.
+        attentions (:obj:`tuple(jax_xla.DeviceArray)`, `optional`, returned when ``output_attentions=True`` is passed or when ``config.output_attentions=True``):
+            Tuple of :obj:`jax_xla.DeviceArray` (one for each layer) of shape :obj:`(batch_size, num_heads,
+            sequence_length, sequence_length)`.
+
+            Attentions weights after the attention softmax, used to compute the weighted average in the self-attention
+            heads.
+    """
+
+    prediction_logits: jax_xla.DeviceArray = None
+    seq_relationship_logits: jax_xla.DeviceArray = None
+    hidden_states: Optional[Tuple[jax_xla.DeviceArray]] = None
+    attentions: Optional[Tuple[jax_xla.DeviceArray]] = None
+
+
 BERT_START_DOCSTRING = r"""
 
     This model inherits from :class:`~transformers.FlaxPreTrainedModel`. Check the superclass documentation for the
@@ -166,7 +215,7 @@ class FlaxBertSelfAttention(nn.Module):
             kernel_init=jax.nn.initializers.normal(self.config.initializer_range, self.dtype),
         )
 
-    def __call__(self, hidden_states, attention_mask, deterministic=True):
+    def __call__(self, hidden_states, attention_mask, deterministic=True, output_attentions: bool = False):
         head_dim = self.config.hidden_size // self.config.num_attention_heads
 
         query_states = self.query(hidden_states).reshape(
@@ -208,7 +257,12 @@ class FlaxBertSelfAttention(nn.Module):
             precision=None,
         )
 
-        return attn_output.reshape(attn_output.shape[:2] + (-1,))
+        outputs = (attn_output.reshape(attn_output.shape[:2] + (-1,)),)
+
+        # TODO: at the moment it's not possible to retrieve attn_weights from
+        # dot_product_attention, but should be in the future -> add functionality then
+
+        return outputs
 
 
 class FlaxBertSelfOutput(nn.Module):
@@ -239,13 +293,22 @@ class FlaxBertAttention(nn.Module):
         self.self = FlaxBertSelfAttention(self.config, dtype=self.dtype)
         self.output = FlaxBertSelfOutput(self.config, dtype=self.dtype)
 
-    def __call__(self, hidden_states, attention_mask, deterministic=True):
+    def __call__(self, hidden_states, attention_mask, deterministic=True, output_attentions: bool = False):
         # Attention mask comes in as attention_mask.shape == (*batch_sizes, kv_length)
         # FLAX expects: attention_mask.shape == (*batch_sizes, 1, 1, kv_length) such that it is broadcastable
         # with attn_weights.shape == (*batch_sizes, num_heads, q_length, kv_length)
-        attn_output = self.self(hidden_states, attention_mask, deterministic=deterministic)
+        attn_outputs = self.self(
+            hidden_states, attention_mask, deterministic=deterministic, output_attentions=output_attentions
+        )
+        attn_output = attn_outputs[0]
         hidden_states = self.output(attn_output, hidden_states, deterministic=deterministic)
-        return hidden_states
+
+        outputs = (hidden_states,)
+
+        if output_attentions:
+            outputs += attn_outputs[1]
+
+        return outputs
 
 
 class FlaxBertIntermediate(nn.Module):
@@ -295,11 +358,20 @@ class FlaxBertLayer(nn.Module):
         self.intermediate = FlaxBertIntermediate(self.config, dtype=self.dtype)
         self.output = FlaxBertOutput(self.config, dtype=self.dtype)
 
-    def __call__(self, hidden_states, attention_mask, deterministic: bool = True):
+    def __call__(self, hidden_states, attention_mask, deterministic: bool = True, output_attentions: bool = False):
-        attention_output = self.attention(hidden_states, attention_mask, deterministic=deterministic)
+        attention_outputs = self.attention(
+            hidden_states, attention_mask, deterministic=deterministic, output_attentions=output_attentions
+        )
+        attention_output = attention_outputs[0]
+
         hidden_states = self.intermediate(attention_output)
         hidden_states = self.output(hidden_states, attention_output, deterministic=deterministic)
-        return hidden_states
+
+        outputs = (hidden_states,)
+
+        if output_attentions:
+            outputs += (attention_outputs[1],)
+        return outputs
 
 
 class FlaxBertLayerCollection(nn.Module):
@@ -311,10 +383,40 @@ class FlaxBertLayerCollection(nn.Module):
             FlaxBertLayer(self.config, name=str(i), dtype=self.dtype) for i in range(self.config.num_hidden_layers)
         ]
 
-    def __call__(self, hidden_states, attention_mask, deterministic: bool = True):
+    def __call__(
+        self,
+        hidden_states,
+        attention_mask,
+        deterministic: bool = True,
+        output_attentions: bool = False,
+        output_hidden_states: bool = False,
+        return_dict: bool = True,
+    ):
+        all_attentions = () if output_attentions else None
+        all_hidden_states = () if output_hidden_states else None
+
         for i, layer in enumerate(self.layers):
-            hidden_states = layer(hidden_states, attention_mask, deterministic=deterministic)
+            if output_hidden_states:
-        return hidden_states
+                all_hidden_states += (hidden_states,)
+
+            layer_outputs = layer(hidden_states, attention_mask, deterministic=deterministic)
+
+            hidden_states = layer_outputs[0]
+
+            if output_attentions:
+                all_attentions += (layer_outputs[1],)
+
+        if output_hidden_states:
+            all_hidden_states += (hidden_states,)
+
+        outputs = (hidden_states,)
+
+        if not return_dict:
+            return tuple(v for v in outputs if v is not None)
+
+        return FlaxBaseModelOutput(
+            last_hidden_state=hidden_states, hidden_states=all_hidden_states, attentions=all_attentions
+        )
 
 
 class FlaxBertEncoder(nn.Module):
@@ -324,8 +426,23 @@ class FlaxBertEncoder(nn.Module):
     def setup(self):
         self.layer = FlaxBertLayerCollection(self.config, dtype=self.dtype)
 
-    def __call__(self, hidden_states, attention_mask, deterministic: bool = True):
+    def __call__(
-        return self.layer(hidden_states, attention_mask, deterministic=deterministic)
+        self,
+        hidden_states,
+        attention_mask,
+        deterministic: bool = True,
+        output_attentions: bool = False,
+        output_hidden_states: bool = False,
+        return_dict: bool = True,
+    ):
+        return self.layer(
+            hidden_states,
+            attention_mask,
+            deterministic=deterministic,
+            output_attentions=output_attentions,
+            output_hidden_states=output_hidden_states,
+            return_dict=return_dict,
+        )
 
 
 class FlaxBertPooler(nn.Module):
@@ -456,7 +573,21 @@ class FlaxBertPreTrainedModel(FlaxPreTrainedModel):
         params: dict = None,
         dropout_rng: PRNGKey = None,
         train: bool = False,
+        output_attentions: Optional[bool] = None,
+        output_hidden_states: Optional[bool] = None,
+        return_dict: Optional[bool] = None,
     ):
+        output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions
+        output_hidden_states = (
+            output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states
+        )
+        return_dict = return_dict if return_dict is not None else self.config.return_dict
+
+        if output_attentions:
+            raise NotImplementedError(
+                "Currently attention scores cannot be returned. Please set `output_attentions` to False for now."
+            )
+
         # init input tensors if not passed
         if token_type_ids is None:
             token_type_ids = jnp.ones_like(input_ids)
@@ -479,6 +610,9 @@ class FlaxBertPreTrainedModel(FlaxPreTrainedModel):
             jnp.array(token_type_ids, dtype="i4"),
             jnp.array(position_ids, dtype="i4"),
             not train,
+            output_attentions,
+            output_hidden_states,
+            return_dict,
             rngs=rngs,
         )
 
@@ -493,17 +627,43 @@ class FlaxBertModule(nn.Module):
         self.encoder = FlaxBertEncoder(self.config, dtype=self.dtype)
         self.pooler = FlaxBertPooler(self.config, dtype=self.dtype)
 
-    def __call__(self, input_ids, attention_mask, token_type_ids, position_ids, deterministic: bool = True):
+    def __call__(
+        self,
+        input_ids,
+        attention_mask,
+        token_type_ids,
+        position_ids,
+        deterministic: bool = True,
+        output_attentions: bool = False,
+        output_hidden_states: bool = False,
+        return_dict: bool = True,
+    ):
         hidden_states = self.embeddings(
             input_ids, token_type_ids, position_ids, attention_mask, deterministic=deterministic
         )
-        hidden_states = self.encoder(hidden_states, attention_mask, deterministic=deterministic)
+        outputs = self.encoder(
+            hidden_states,
+            attention_mask,
+            deterministic=deterministic,
+            output_attentions=output_attentions,
+            output_hidden_states=output_hidden_states,
+            return_dict=return_dict,
+        )
+        hidden_states = outputs[0]
+        pooled = self.pooler(hidden_states) if self.add_pooling_layer else None
 
-        if not self.add_pooling_layer:
+        if not return_dict:
-            return hidden_states
+            # if pooled is None, don't return it
+            if pooled is None:
+                return (hidden_states,) + outputs[1:]
+            return (hidden_states, pooled) + outputs[1:]
 
-        pooled = self.pooler(hidden_states)
+        return FlaxBaseModelOutputWithPooling(
-        return hidden_states, pooled
+            last_hidden_state=hidden_states,
+            pooler_output=pooled,
+            hidden_states=outputs.hidden_states,
+            attentions=outputs.attentions,
+        )
 
 
 @add_start_docstrings(
@@ -514,6 +674,11 @@ class FlaxBertModel(FlaxBertPreTrainedModel):
     module_class = FlaxBertModule
 
 
+append_call_sample_docstring(
+    FlaxBertModel, _TOKENIZER_FOR_DOC, _CHECKPOINT_FOR_DOC, FlaxBaseModelOutputWithPooling, _CONFIG_FOR_DOC
+)
+
+
 class FlaxBertForPreTrainingModule(nn.Module):
     config: BertConfig
     dtype: jnp.dtype = jnp.float32
@@ -523,11 +688,27 @@ class FlaxBertForPreTrainingModule(nn.Module):
         self.cls = FlaxBertPreTrainingHeads(config=self.config, dtype=self.dtype)
 
     def __call__(
-        self, input_ids, attention_mask=None, token_type_ids=None, position_ids=None, deterministic: bool = True
+        self,
+        input_ids,
+        attention_mask,
+        token_type_ids,
+        position_ids,
+        deterministic: bool = True,
+        output_attentions: bool = False,
+        output_hidden_states: bool = False,
+        return_dict: bool = True,
     ):
+
         # Model
-        hidden_states, pooled_output = self.bert(
+        outputs = self.bert(
-            input_ids, attention_mask, token_type_ids, position_ids, deterministic=deterministic
+            input_ids,
+            attention_mask,
+            token_type_ids,
+            position_ids,
+            deterministic=deterministic,
+            output_attentions=output_attentions,
+            output_hidden_states=output_hidden_states,
+            return_dict=return_dict,
         )
 
         if self.config.tie_word_embeddings:
@@ -535,11 +716,22 @@ class FlaxBertForPreTrainingModule(nn.Module):
         else:
             shared_embedding = None
 
+        hidden_states = outputs[0]
+        pooled_output = outputs[1]
+
         prediction_scores, seq_relationship_score = self.cls(
             hidden_states, pooled_output, shared_embedding=shared_embedding
         )
 
-        return (prediction_scores, seq_relationship_score)
+        if not return_dict:
+            return (prediction_scores, seq_relationship_score) + outputs[2:]
+
+        return FlaxBertForPreTrainingOutput(
+            prediction_logits=prediction_scores,
+            seq_relationship_logits=seq_relationship_score,
+            hidden_states=outputs.hidden_states,
+            attentions=outputs.attentions,
+        )
 
 
 @add_start_docstrings(
@@ -553,6 +745,32 @@ class FlaxBertForPreTraining(FlaxBertPreTrainedModel):
     module_class = FlaxBertForPreTrainingModule
 
 
+FLAX_BERT_FOR_PRETRAINING_DOCSTRING = """
+    Returns:
+
+    Example::
+
+        >>> from transformers import BertTokenizer, FlaxBertForPreTraining
+
+        >>> tokenizer = BertTokenizer.from_pretrained('bert-base-uncased')
+        >>> model = FlaxBertForPreTraining.from_pretrained('bert-base-uncased')
+
+        >>> inputs = tokenizer("Hello, my dog is cute", return_tensors="jax")
+        >>> outputs = model(**inputs)
+
+        >>> prediction_logits = outputs.prediction_logits
+        >>> seq_relationship_logits = outputs.seq_relationship_logits
+"""
+
+overwrite_call_docstring(
+    FlaxBertForPreTraining,
+    BERT_INPUTS_DOCSTRING.format("batch_size, sequence_length") + FLAX_BERT_FOR_PRETRAINING_DOCSTRING,
+)
+append_replace_return_docstrings(
+    FlaxBertForPreTraining, output_type=FlaxBertForPreTrainingOutput, config_class=_CONFIG_FOR_DOC
+)
+
+
 class FlaxBertForMaskedLMModule(nn.Module):
     config: BertConfig
     dtype: jnp.dtype = jnp.float32
@@ -562,11 +780,29 @@ class FlaxBertForMaskedLMModule(nn.Module):
         self.cls = FlaxBertOnlyMLMHead(config=self.config, dtype=self.dtype)
 
     def __call__(
-        self, input_ids, attention_mask=None, token_type_ids=None, position_ids=None, deterministic: bool = True
+        self,
+        input_ids,
+        attention_mask,
+        token_type_ids,
+        position_ids,
+        deterministic: bool = True,
+        output_attentions: bool = False,
+        output_hidden_states: bool = False,
+        return_dict: bool = True,
     ):
         # Model
-        hidden_states = self.bert(input_ids, attention_mask, token_type_ids, position_ids, deterministic=deterministic)
+        outputs = self.bert(
+            input_ids,
+            attention_mask,
+            token_type_ids,
+            position_ids,
+            deterministic=deterministic,
+            output_attentions=output_attentions,
+            output_hidden_states=output_hidden_states,
+            return_dict=return_dict,
+        )
 
+        hidden_states = outputs[0]
         if self.config.tie_word_embeddings:
             shared_embedding = self.bert.variables["params"]["embeddings"]["word_embeddings"]["embedding"]
         else:
@@ -575,7 +811,14 @@ class FlaxBertForMaskedLMModule(nn.Module):
         # Compute the prediction scores
         logits = self.cls(hidden_states, shared_embedding=shared_embedding)
 
-        return (logits,)
+        if not return_dict:
+            return (logits,) + outputs[1:]
+
+        return FlaxMaskedLMOutput(
+            logits=logits,
+            hidden_states=outputs.hidden_states,
+            attentions=outputs.attentions,
+        )
 
 
 @add_start_docstrings("""Bert Model with a `language modeling` head on top. """, BERT_START_DOCSTRING)
@@ -583,6 +826,11 @@ class FlaxBertForMaskedLM(FlaxBertPreTrainedModel):
     module_class = FlaxBertForMaskedLMModule
 
 
+append_call_sample_docstring(
+    FlaxBertForMaskedLM, _TOKENIZER_FOR_DOC, _CHECKPOINT_FOR_DOC, FlaxMaskedLMOutput, _CONFIG_FOR_DOC
+)
+
+
 class FlaxBertForNextSentencePredictionModule(nn.Module):
     config: BertConfig
     dtype: jnp.dtype = jnp.float32
@@ -592,15 +840,41 @@ class FlaxBertForNextSentencePredictionModule(nn.Module):
         self.cls = FlaxBertOnlyNSPHead(dtype=self.dtype)
 
     def __call__(
-        self, input_ids, attention_mask=None, token_type_ids=None, position_ids=None, deterministic: bool = True
+        self,
+        input_ids,
+        attention_mask,
+        token_type_ids,
+        position_ids,
+        deterministic: bool = True,
+        output_attentions: bool = False,
+        output_hidden_states: bool = False,
+        return_dict: bool = True,
     ):
+        return_dict = return_dict if return_dict is not None else self.config.return_dict
+
         # Model
-        _, pooled_output = self.bert(
+        outputs = self.bert(
-            input_ids, attention_mask, token_type_ids, position_ids, deterministic=deterministic
+            input_ids,
+            attention_mask,
+            token_type_ids,
+            position_ids,
+            deterministic=deterministic,
+            output_attentions=output_attentions,
+            output_hidden_states=output_hidden_states,
+            return_dict=return_dict,
         )
 
+        pooled_output = outputs[1]
         seq_relationship_scores = self.cls(pooled_output)
-        return (seq_relationship_scores,)
+
+        if not return_dict:
+            return (seq_relationship_scores,) + outputs[2:]
+
+        return FlaxNextSentencePredictorOutput(
+            logits=seq_relationship_scores,
+            hidden_states=outputs.hidden_states,
+            attentions=outputs.attentions,
+        )
 
 
 @add_start_docstrings(
@@ -611,6 +885,35 @@ class FlaxBertForNextSentencePrediction(FlaxBertPreTrainedModel):
     module_class = FlaxBertForNextSentencePredictionModule
 
 
+FLAX_BERT_FOR_NEXT_SENT_PRED_DOCSTRING = """
+    Returns:
+
+    Example::
+
+        >>> from transformers import BertTokenizer, FlaxBertForNextSentencePrediction
+
+        >>> tokenizer = BertTokenizer.from_pretrained('bert-base-uncased')
+        >>> model = FlaxBertForNextSentencePrediction.from_pretrained('bert-base-uncased')
+
+        >>> prompt = "In Italy, pizza served in formal settings, such as at a restaurant, is presented unsliced."
+        >>> next_sentence = "The sky is blue due to the shorter wavelength of blue light."
+        >>> encoding = tokenizer(prompt, next_sentence, return_tensors='jax')
+
+        >>> outputs = model(**encoding)
+        >>> logits = outputs.logits
+        >>> assert logits[0, 0] < logits[0, 1] # next sentence was random
+"""
+
+
+overwrite_call_docstring(
+    FlaxBertForNextSentencePrediction,
+    BERT_INPUTS_DOCSTRING.format("batch_size, sequence_length") + FLAX_BERT_FOR_NEXT_SENT_PRED_DOCSTRING,
+)
+append_replace_return_docstrings(
+    FlaxBertForNextSentencePrediction, output_type=FlaxNextSentencePredictorOutput, config_class=_CONFIG_FOR_DOC
+)
+
+
 class FlaxBertForSequenceClassificationModule(nn.Module):
     config: BertConfig
     dtype: jnp.dtype = jnp.float32
@@ -624,17 +927,40 @@ class FlaxBertForSequenceClassificationModule(nn.Module):
         )
 
     def __call__(
-        self, input_ids, attention_mask=None, token_type_ids=None, position_ids=None, deterministic: bool = True
+        self,
+        input_ids,
+        attention_mask,
+        token_type_ids,
+        position_ids,
+        deterministic: bool = True,
+        output_attentions: bool = False,
+        output_hidden_states: bool = False,
+        return_dict: bool = True,
     ):
         # Model
-        _, pooled_output = self.bert(
+        outputs = self.bert(
-            input_ids, attention_mask, token_type_ids, position_ids, deterministic=deterministic
+            input_ids,
+            attention_mask,
+            token_type_ids,
+            position_ids,
+            deterministic=deterministic,
+            output_attentions=output_attentions,
+            output_hidden_states=output_hidden_states,
+            return_dict=return_dict,
         )
 
+        pooled_output = outputs[1]
         pooled_output = self.dropout(pooled_output, deterministic=deterministic)
         logits = self.classifier(pooled_output)
 
-        return (logits,)
+        if not return_dict:
+            return (logits,) + outputs[2:]
+
+        return FlaxSequenceClassifierOutput(
+            logits=logits,
+            hidden_states=outputs.hidden_states,
+            attentions=outputs.attentions,
+        )
 
 
 @add_start_docstrings(
@@ -648,6 +974,15 @@ class FlaxBertForSequenceClassification(FlaxBertPreTrainedModel):
     module_class = FlaxBertForSequenceClassificationModule
 
 
+append_call_sample_docstring(
+    FlaxBertForSequenceClassification,
+    _TOKENIZER_FOR_DOC,
+    _CHECKPOINT_FOR_DOC,
+    FlaxSequenceClassifierOutput,
+    _CONFIG_FOR_DOC,
+)
+
+
 class FlaxBertForMultipleChoiceModule(nn.Module):
     config: BertConfig
     dtype: jnp.dtype = jnp.float32
@@ -658,7 +993,15 @@ class FlaxBertForMultipleChoiceModule(nn.Module):
         self.classifier = nn.Dense(1, dtype=self.dtype)
 
     def __call__(
-        self, input_ids, attention_mask=None, token_type_ids=None, position_ids=None, deterministic: bool = True
+        self,
+        input_ids,
+        attention_mask,
+        token_type_ids,
+        position_ids,
+        deterministic: bool = True,
+        output_attentions: bool = False,
+        output_hidden_states: bool = False,
+        return_dict: bool = True,
     ):
         num_choices = input_ids.shape[1]
         input_ids = input_ids.reshape(-1, input_ids.shape[-1]) if input_ids is not None else None
@@ -667,16 +1010,31 @@ class FlaxBertForMultipleChoiceModule(nn.Module):
         position_ids = position_ids.reshape(-1, position_ids.shape[-1]) if position_ids is not None else None
 
         # Model
-        _, pooled_output = self.bert(
+        outputs = self.bert(
-            input_ids, attention_mask, token_type_ids, position_ids, deterministic=deterministic
+            input_ids,
+            attention_mask,
+            token_type_ids,
+            position_ids,
+            deterministic=deterministic,
+            output_attentions=output_attentions,
+            output_hidden_states=output_hidden_states,
+            return_dict=return_dict,
         )
 
+        pooled_output = outputs[1]
         pooled_output = self.dropout(pooled_output, deterministic=deterministic)
         logits = self.classifier(pooled_output)
 
         reshaped_logits = logits.reshape(-1, num_choices)
 
-        return (reshaped_logits,)
+        if not return_dict:
+            return (reshaped_logits,) + outputs[2:]
+
+        return FlaxMultipleChoiceModelOutput(
+            logits=reshaped_logits,
+            hidden_states=outputs.hidden_states,
+            attentions=outputs.attentions,
+        )
 
 
 @add_start_docstrings(
@@ -690,10 +1048,12 @@ class FlaxBertForMultipleChoice(FlaxBertPreTrainedModel):
     module_class = FlaxBertForMultipleChoiceModule
 
 
-# adapt docstring slightly for FlaxBertForMultipleChoice
 overwrite_call_docstring(
     FlaxBertForMultipleChoice, BERT_INPUTS_DOCSTRING.format("batch_size, num_choices, sequence_length")
 )
+append_call_sample_docstring(
+    FlaxBertForMultipleChoice, _TOKENIZER_FOR_DOC, _CHECKPOINT_FOR_DOC, FlaxMultipleChoiceModelOutput, _CONFIG_FOR_DOC
+)
 
 
 class FlaxBertForTokenClassificationModule(nn.Module):
@@ -706,15 +1066,40 @@ class FlaxBertForTokenClassificationModule(nn.Module):
         self.classifier = nn.Dense(self.config.num_labels, dtype=self.dtype)
 
     def __call__(
-        self, input_ids, attention_mask=None, token_type_ids=None, position_ids=None, deterministic: bool = True
+        self,
+        input_ids,
+        attention_mask,
+        token_type_ids,
+        position_ids,
+        deterministic: bool = True,
+        output_attentions: bool = False,
+        output_hidden_states: bool = False,
+        return_dict: bool = True,
     ):
         # Model
-        hidden_states = self.bert(input_ids, attention_mask, token_type_ids, position_ids, deterministic=deterministic)
+        outputs = self.bert(
+            input_ids,
+            attention_mask,
+            token_type_ids,
+            position_ids,
+            deterministic=deterministic,
+            output_attentions=output_attentions,
+            output_hidden_states=output_hidden_states,
+            return_dict=return_dict,
+        )
 
+        hidden_states = outputs[0]
         hidden_states = self.dropout(hidden_states, deterministic=deterministic)
         logits = self.classifier(hidden_states)
 
-        return (logits,)
+        if not return_dict:
+            return (logits,) + outputs[1:]
+
+        return FlaxTokenClassifierOutput(
+            logits=logits,
+            hidden_states=outputs.hidden_states,
+            attentions=outputs.attentions,
+        )
 
 
 @add_start_docstrings(
@@ -728,6 +1113,11 @@ class FlaxBertForTokenClassification(FlaxBertPreTrainedModel):
     module_class = FlaxBertForTokenClassificationModule
 
 
+append_call_sample_docstring(
+    FlaxBertForTokenClassification, _TOKENIZER_FOR_DOC, _CHECKPOINT_FOR_DOC, FlaxTokenClassifierOutput, _CONFIG_FOR_DOC
+)
+
+
 class FlaxBertForQuestionAnsweringModule(nn.Module):
     config: BertConfig
     dtype: jnp.dtype = jnp.float32
@@ -737,17 +1127,44 @@ class FlaxBertForQuestionAnsweringModule(nn.Module):
         self.qa_outputs = nn.Dense(self.config.num_labels, dtype=self.dtype)
 
     def __call__(
-        self, input_ids, attention_mask=None, token_type_ids=None, position_ids=None, deterministic: bool = True
+        self,
+        input_ids,
+        attention_mask,
+        token_type_ids,
+        position_ids,
+        deterministic: bool = True,
+        output_attentions: bool = False,
+        output_hidden_states: bool = False,
+        return_dict: bool = True,
     ):
         # Model
-        hidden_states = self.bert(input_ids, attention_mask, token_type_ids, position_ids, deterministic=deterministic)
+        outputs = self.bert(
+            input_ids,
+            attention_mask,
+            token_type_ids,
+            position_ids,
+            deterministic=deterministic,
+            output_attentions=output_attentions,
+            output_hidden_states=output_hidden_states,
+            return_dict=return_dict,
+        )
+
+        hidden_states = outputs[0]
 
         logits = self.qa_outputs(hidden_states)
         start_logits, end_logits = logits.split(self.config.num_labels, axis=-1)
         start_logits = start_logits.squeeze(-1)
         end_logits = end_logits.squeeze(-1)
 
-        return (start_logits, end_logits)
+        if not return_dict:
+            return (start_logits, end_logits) + outputs[1:]
+
+        return FlaxQuestionAnsweringModelOutput(
+            start_logits=start_logits,
+            end_logits=end_logits,
+            hidden_states=outputs.hidden_states,
+            attentions=outputs.attentions,
+        )
 
 
 @add_start_docstrings(
@@ -759,3 +1176,12 @@ class FlaxBertForQuestionAnsweringModule(nn.Module):
 )
 class FlaxBertForQuestionAnswering(FlaxBertPreTrainedModel):
     module_class = FlaxBertForQuestionAnsweringModule
+
+
+append_call_sample_docstring(
+    FlaxBertForQuestionAnswering,
+    _TOKENIZER_FOR_DOC,
+    _CHECKPOINT_FOR_DOC,
+    FlaxQuestionAnsweringModelOutput,
+    _CONFIG_FOR_DOC,
+)

src/transformers/models/roberta/modeling_flax_roberta.py

@@ -12,7 +12,7 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-from typing import Tuple
+from typing import Optional, Tuple
 
 import flax.linen as nn
 import jax
@@ -23,13 +23,15 @@ from jax import lax
 from jax.random import PRNGKey
 
 from ...file_utils import add_start_docstrings, add_start_docstrings_to_model_forward
-from ...modeling_flax_utils import ACT2FN, FlaxPreTrainedModel
+from ...modeling_flax_outputs import FlaxBaseModelOutput, FlaxBaseModelOutputWithPooling
+from ...modeling_flax_utils import ACT2FN, FlaxPreTrainedModel, append_call_sample_docstring
 from ...utils import logging
 from .configuration_roberta import RobertaConfig
 
 
 logger = logging.get_logger(__name__)
 
+_CHECKPOINT_FOR_DOC = "roberta-base"
 _CONFIG_FOR_DOC = "RobertaConfig"
 _TOKENIZER_FOR_DOC = "RobertaTokenizer"
 
@@ -181,7 +183,7 @@ class FlaxRobertaSelfAttention(nn.Module):
             kernel_init=jax.nn.initializers.normal(self.config.initializer_range, self.dtype),
         )
 
-    def __call__(self, hidden_states, attention_mask, deterministic=True):
+    def __call__(self, hidden_states, attention_mask, deterministic=True, output_attentions: bool = False):
         head_dim = self.config.hidden_size // self.config.num_attention_heads
 
         query_states = self.query(hidden_states).reshape(
@@ -223,7 +225,12 @@ class FlaxRobertaSelfAttention(nn.Module):
             precision=None,
         )
 
-        return attn_output.reshape(attn_output.shape[:2] + (-1,))
+        outputs = (attn_output.reshape(attn_output.shape[:2] + (-1,)),)
+
+        # TODO: at the moment it's not possible to retrieve attn_weights from
+        # dot_product_attention, but should be in the future -> add functionality then
+
+        return outputs
 
 
 # Copied from transformers.models.bert.modeling_flax_bert.FlaxBertSelfOutput with Bert->Roberta
@@ -256,13 +263,22 @@ class FlaxRobertaAttention(nn.Module):
         self.self = FlaxRobertaSelfAttention(self.config, dtype=self.dtype)
         self.output = FlaxRobertaSelfOutput(self.config, dtype=self.dtype)
 
-    def __call__(self, hidden_states, attention_mask, deterministic=True):
+    def __call__(self, hidden_states, attention_mask, deterministic=True, output_attentions: bool = False):
         # Attention mask comes in as attention_mask.shape == (*batch_sizes, kv_length)
         # FLAX expects: attention_mask.shape == (*batch_sizes, 1, 1, kv_length) such that it is broadcastable
         # with attn_weights.shape == (*batch_sizes, num_heads, q_length, kv_length)
-        attn_output = self.self(hidden_states, attention_mask, deterministic=deterministic)
+        attn_outputs = self.self(
+            hidden_states, attention_mask, deterministic=deterministic, output_attentions=output_attentions
+        )
+        attn_output = attn_outputs[0]
         hidden_states = self.output(attn_output, hidden_states, deterministic=deterministic)
-        return hidden_states
+
+        outputs = (hidden_states,)
+
+        if output_attentions:
+            outputs += attn_outputs[1]
+
+        return outputs
 
 
 # Copied from transformers.models.bert.modeling_flax_bert.FlaxBertIntermediate with Bert->Roberta
@@ -315,11 +331,20 @@ class FlaxRobertaLayer(nn.Module):
         self.intermediate = FlaxRobertaIntermediate(self.config, dtype=self.dtype)
         self.output = FlaxRobertaOutput(self.config, dtype=self.dtype)
 
-    def __call__(self, hidden_states, attention_mask, deterministic: bool = True):
+    def __call__(self, hidden_states, attention_mask, deterministic: bool = True, output_attentions: bool = False):
-        attention_output = self.attention(hidden_states, attention_mask, deterministic=deterministic)
+        attention_outputs = self.attention(
+            hidden_states, attention_mask, deterministic=deterministic, output_attentions=output_attentions
+        )
+        attention_output = attention_outputs[0]
+
         hidden_states = self.intermediate(attention_output)
         hidden_states = self.output(hidden_states, attention_output, deterministic=deterministic)
-        return hidden_states
+
+        outputs = (hidden_states,)
+
+        if output_attentions:
+            outputs += (attention_outputs[1],)
+        return outputs
 
 
 # Copied from transformers.models.bert.modeling_flax_bert.FlaxBertLayerCollection with Bert->Roberta
@@ -332,10 +357,40 @@ class FlaxRobertaLayerCollection(nn.Module):
             FlaxRobertaLayer(self.config, name=str(i), dtype=self.dtype) for i in range(self.config.num_hidden_layers)
         ]
 
-    def __call__(self, hidden_states, attention_mask, deterministic: bool = True):
+    def __call__(
+        self,
+        hidden_states,
+        attention_mask,
+        deterministic: bool = True,
+        output_attentions: bool = False,
+        output_hidden_states: bool = False,
+        return_dict: bool = True,
+    ):
+        all_attentions = () if output_attentions else None
+        all_hidden_states = () if output_hidden_states else None
+
         for i, layer in enumerate(self.layers):
-            hidden_states = layer(hidden_states, attention_mask, deterministic=deterministic)
+            if output_hidden_states:
-        return hidden_states
+                all_hidden_states += (hidden_states,)
+
+            layer_outputs = layer(hidden_states, attention_mask, deterministic=deterministic)
+
+            hidden_states = layer_outputs[0]
+
+            if output_attentions:
+                all_attentions += (layer_outputs[1],)
+
+        if output_hidden_states:
+            all_hidden_states += (hidden_states,)
+
+        outputs = (hidden_states,)
+
+        if not return_dict:
+            return tuple(v for v in outputs if v is not None)
+
+        return FlaxBaseModelOutput(
+            last_hidden_state=hidden_states, hidden_states=all_hidden_states, attentions=all_attentions
+        )
 
 
 # Copied from transformers.models.bert.modeling_flax_bert.FlaxBertEncoder with Bert->Roberta
@@ -346,8 +401,23 @@ class FlaxRobertaEncoder(nn.Module):
     def setup(self):
         self.layer = FlaxRobertaLayerCollection(self.config, dtype=self.dtype)
 
-    def __call__(self, hidden_states, attention_mask, deterministic: bool = True):
+    def __call__(
-        return self.layer(hidden_states, attention_mask, deterministic=deterministic)
+        self,
+        hidden_states,
+        attention_mask,
+        deterministic: bool = True,
+        output_attentions: bool = False,
+        output_hidden_states: bool = False,
+        return_dict: bool = True,
+    ):
+        return self.layer(
+            hidden_states,
+            attention_mask,
+            deterministic=deterministic,
+            output_attentions=output_attentions,
+            output_hidden_states=output_hidden_states,
+            return_dict=return_dict,
+        )
 
 
 # Copied from transformers.models.bert.modeling_flax_bert.FlaxBertPooler with Bert->Roberta
@@ -412,7 +482,21 @@ class FlaxRobertaPreTrainedModel(FlaxPreTrainedModel):
         params: dict = None,
         dropout_rng: PRNGKey = None,
         train: bool = False,
+        output_attentions: Optional[bool] = None,
+        output_hidden_states: Optional[bool] = None,
+        return_dict: Optional[bool] = None,
     ):
+        output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions
+        output_hidden_states = (
+            output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states
+        )
+        return_dict = return_dict if return_dict is not None else self.config.return_dict
+
+        if output_attentions:
+            raise NotImplementedError(
+                "Currently attention scores cannot be returned." "Please set `output_attentions` to False for now."
+            )
+
         # init input tensors if not passed
         if token_type_ids is None:
             token_type_ids = jnp.ones_like(input_ids)
@@ -435,6 +519,9 @@ class FlaxRobertaPreTrainedModel(FlaxPreTrainedModel):
             jnp.array(token_type_ids, dtype="i4"),
             jnp.array(position_ids, dtype="i4"),
             not train,
+            output_attentions,
+            output_hidden_states,
+            return_dict,
             rngs=rngs,
         )
 
@@ -450,17 +537,43 @@ class FlaxRobertaModule(nn.Module):
         self.encoder = FlaxRobertaEncoder(self.config, dtype=self.dtype)
         self.pooler = FlaxRobertaPooler(self.config, dtype=self.dtype)
 
-    def __call__(self, input_ids, attention_mask, token_type_ids, position_ids, deterministic: bool = True):
+    def __call__(
+        self,
+        input_ids,
+        attention_mask,
+        token_type_ids,
+        position_ids,
+        deterministic: bool = True,
+        output_attentions: bool = False,
+        output_hidden_states: bool = False,
+        return_dict: bool = True,
+    ):
         hidden_states = self.embeddings(
             input_ids, token_type_ids, position_ids, attention_mask, deterministic=deterministic
         )
-        hidden_states = self.encoder(hidden_states, attention_mask, deterministic=deterministic)
+        outputs = self.encoder(
+            hidden_states,
+            attention_mask,
+            deterministic=deterministic,
+            output_attentions=output_attentions,
+            output_hidden_states=output_hidden_states,
+            return_dict=return_dict,
+        )
+        hidden_states = outputs[0]
+        pooled = self.pooler(hidden_states) if self.add_pooling_layer else None
 
-        if not self.add_pooling_layer:
+        if not return_dict:
-            return hidden_states
+            # if pooled is None, don't return it
+            if pooled is None:
+                return (hidden_states,) + outputs[1:]
+            return (hidden_states, pooled) + outputs[1:]
 
-        pooled = self.pooler(hidden_states)
+        return FlaxBaseModelOutputWithPooling(
-        return hidden_states, pooled
+            last_hidden_state=hidden_states,
+            pooler_output=pooled,
+            hidden_states=outputs.hidden_states,
+            attentions=outputs.attentions,
+        )
 
 
 @add_start_docstrings(
@@ -469,3 +582,8 @@ class FlaxRobertaModule(nn.Module):
 )
 class FlaxRobertaModel(FlaxRobertaPreTrainedModel):
     module_class = FlaxRobertaModule
+
+
+append_call_sample_docstring(
+    FlaxRobertaModel, _TOKENIZER_FOR_DOC, _CHECKPOINT_FOR_DOC, FlaxBaseModelOutputWithPooling, _CONFIG_FOR_DOC
+)

tests/test_modeling_common.py

@@ -998,7 +998,6 @@ class ModelTesterMixin:
             # self.assertTrue(check_same_values(model.transformer.wte, model.lm_head))
 
     def test_model_outputs_equivalence(self):
-
         config, inputs_dict = self.model_tester.prepare_config_and_inputs_for_common()
 
         def set_nan_tensor_to_zero(t):

tests/test_modeling_flax_common.py

@@ -13,8 +13,10 @@
 # limitations under the License.
 
 import copy
+import inspect
 import random
 import tempfile
+from typing import List, Tuple
 
 import numpy as np
 
@@ -28,6 +30,7 @@ if is_flax_available():
 
     import jax
     import jax.numpy as jnp
+    import jaxlib.xla_extension as jax_xla
     from transformers.modeling_flax_pytorch_utils import (
         convert_pytorch_state_dict_to_flax,
         load_flax_weights_in_pytorch_model,
@@ -77,6 +80,7 @@ class FlaxModelTesterMixin:
             inputs_dict = {
                 k: jnp.broadcast_to(v[:, None], (v.shape[0], self.model_tester.num_choices, v.shape[-1]))
                 for k, v in inputs_dict.items()
+                if isinstance(v, (jax_xla.DeviceArray, np.ndarray))
             }
 
         return inputs_dict
@@ -85,6 +89,41 @@ class FlaxModelTesterMixin:
         diff = np.abs((a - b)).max()
         self.assertLessEqual(diff, tol, f"Difference between torch and flax is {diff} (>= {tol}).")
 
+    def test_model_outputs_equivalence(self):
+        config, inputs_dict = self.model_tester.prepare_config_and_inputs_for_common()
+
+        def set_nan_tensor_to_zero(t):
+            t[t != t] = 0
+            return t
+
+        def check_equivalence(model, tuple_inputs, dict_inputs, additional_kwargs={}):
+            tuple_output = model(**tuple_inputs, return_dict=False, **additional_kwargs)
+            dict_output = model(**dict_inputs, return_dict=True, **additional_kwargs).to_tuple()
+
+            def recursive_check(tuple_object, dict_object):
+                if isinstance(tuple_object, (List, Tuple)):
+                    for tuple_iterable_value, dict_iterable_value in zip(tuple_object, dict_object):
+                        recursive_check(tuple_iterable_value, dict_iterable_value)
+                elif tuple_object is None:
+                    return
+                else:
+                    self.assert_almost_equals(
+                        set_nan_tensor_to_zero(tuple_object), set_nan_tensor_to_zero(dict_object), 1e-5
+                    )
+
+                recursive_check(tuple_output, dict_output)
+
+        for model_class in self.all_model_classes:
+            model = model_class(config)
+
+            tuple_inputs = self._prepare_for_class(inputs_dict, model_class)
+            dict_inputs = self._prepare_for_class(inputs_dict, model_class)
+            check_equivalence(model, tuple_inputs, dict_inputs)
+
+            tuple_inputs = self._prepare_for_class(inputs_dict, model_class)
+            dict_inputs = self._prepare_for_class(inputs_dict, model_class)
+            check_equivalence(model, tuple_inputs, dict_inputs, {"output_hidden_states": True})
+
     @is_pt_flax_cross_test
     def test_equivalence_pt_to_flax(self):
         config, inputs_dict = self.model_tester.prepare_config_and_inputs_for_common()
@@ -108,7 +147,7 @@ class FlaxModelTesterMixin:
                 with torch.no_grad():
                     pt_outputs = pt_model(**pt_inputs).to_tuple()
 
-                fx_outputs = fx_model(**prepared_inputs_dict)
+                fx_outputs = fx_model(**prepared_inputs_dict).to_tuple()
                 self.assertEqual(len(fx_outputs), len(pt_outputs), "Output lengths differ between Flax and PyTorch")
                 for fx_output, pt_output in zip(fx_outputs, pt_outputs):
                     self.assert_almost_equals(fx_output, pt_output.numpy(), 1e-3)
@@ -117,7 +156,7 @@ class FlaxModelTesterMixin:
                     pt_model.save_pretrained(tmpdirname)
                     fx_model_loaded = model_class.from_pretrained(tmpdirname, from_pt=True)
 
-                fx_outputs_loaded = fx_model_loaded(**prepared_inputs_dict)
+                fx_outputs_loaded = fx_model_loaded(**prepared_inputs_dict).to_tuple()
                 self.assertEqual(
                     len(fx_outputs_loaded), len(pt_outputs), "Output lengths differ between Flax and PyTorch"
                 )
@@ -149,7 +188,7 @@ class FlaxModelTesterMixin:
                 with torch.no_grad():
                     pt_outputs = pt_model(**pt_inputs).to_tuple()
 
-                fx_outputs = fx_model(**prepared_inputs_dict)
+                fx_outputs = fx_model(**prepared_inputs_dict).to_tuple()
                 self.assertEqual(len(fx_outputs), len(pt_outputs), "Output lengths differ between Flax and PyTorch")
                 for fx_output, pt_output in zip(fx_outputs, pt_outputs):
                     self.assert_almost_equals(fx_output, pt_output.numpy(), 1e-3)
@@ -171,17 +210,20 @@ class FlaxModelTesterMixin:
         config, inputs_dict = self.model_tester.prepare_config_and_inputs_for_common()
 
         for model_class in self.all_model_classes:
+            if model_class.__name__ != "FlaxBertModel":
+                continue
+
             with self.subTest(model_class.__name__):
                 model = model_class(config)
 
                 prepared_inputs_dict = self._prepare_for_class(inputs_dict, model_class)
-                outputs = model(**prepared_inputs_dict)
+                outputs = model(**prepared_inputs_dict).to_tuple()
 
                 with tempfile.TemporaryDirectory() as tmpdirname:
                     model.save_pretrained(tmpdirname)
                     model_loaded = model_class.from_pretrained(tmpdirname)
 
-                outputs_loaded = model_loaded(**prepared_inputs_dict)
+                outputs_loaded = model_loaded(**prepared_inputs_dict).to_tuple()
                 for output_loaded, output in zip(outputs_loaded, outputs):
                     self.assert_almost_equals(output_loaded, output, 1e-3)
 
@@ -195,19 +237,47 @@ class FlaxModelTesterMixin:
 
                 @jax.jit
                 def model_jitted(input_ids, attention_mask=None, token_type_ids=None):
-                    return model(input_ids, attention_mask, token_type_ids)
+                    return model(
+                        input_ids=input_ids,
+                        attention_mask=attention_mask,
+                        token_type_ids=token_type_ids,
+                    ).to_tuple()
+
+                with self.subTest("JIT Enabled"):
+                    jitted_outputs = model_jitted(**prepared_inputs_dict)
 
                 with self.subTest("JIT Disabled"):
                     with jax.disable_jit():
                         outputs = model_jitted(**prepared_inputs_dict)
 
-                with self.subTest("JIT Enabled"):
-                    jitted_outputs = model_jitted(**prepared_inputs_dict)
-
                 self.assertEqual(len(outputs), len(jitted_outputs))
                 for jitted_output, output in zip(jitted_outputs, outputs):
                     self.assertEqual(jitted_output.shape, output.shape)
 
+                @jax.jit
+                def model_jitted_return_dict(input_ids, attention_mask=None, token_type_ids=None):
+                    return model(
+                        input_ids=input_ids,
+                        attention_mask=attention_mask,
+                        token_type_ids=token_type_ids,
+                    )
+
+                # jitted function cannot return OrderedDict
+                with self.assertRaises(TypeError):
+                    model_jitted_return_dict(**prepared_inputs_dict)
+
+    def test_forward_signature(self):
+        config, _ = self.model_tester.prepare_config_and_inputs_for_common()
+
+        for model_class in self.all_model_classes:
+            model = model_class(config)
+            signature = inspect.signature(model.__call__)
+            # signature.parameters is an OrderedDict => so arg_names order is deterministic
+            arg_names = [*signature.parameters.keys()]
+
+            expected_arg_names = ["input_ids", "attention_mask"]
+            self.assertListEqual(arg_names[:2], expected_arg_names)
+
     def test_naming_convention(self):
         for model_class in self.all_model_classes:
             model_class_name = model_class.__name__
@@ -218,3 +288,30 @@ class FlaxModelTesterMixin:
             module_cls = getattr(bert_modeling_flax_module, module_class_name)
 
             self.assertIsNotNone(module_cls)
+
+    def test_hidden_states_output(self):
+        def check_hidden_states_output(inputs_dict, config, model_class):
+            model = model_class(config)
+
+            outputs = model(**self._prepare_for_class(inputs_dict, model_class))
+            hidden_states = outputs.hidden_states
+
+            self.assertEqual(len(hidden_states), self.model_tester.num_hidden_layers + 1)
+            seq_length = self.model_tester.seq_length
+
+            self.assertListEqual(
+                list(hidden_states[0].shape[-2:]),
+                [seq_length, self.model_tester.hidden_size],
+            )
+
+        config, inputs_dict = self.model_tester.prepare_config_and_inputs_for_common()
+
+        for model_class in self.all_model_classes:
+            inputs_dict["output_hidden_states"] = True
+            check_hidden_states_output(inputs_dict, config, model_class)
+
+            # check that output_hidden_states also work using config
+            del inputs_dict["output_hidden_states"]
+            config.output_hidden_states = True
+
+            check_hidden_states_output(inputs_dict, config, model_class)