device agnostic models testing (#27146)

* device agnostic models testing

* add decorator `require_torch_fp16`

* make style

* apply review suggestion

* Oops, the fp16 decorator was misused

tests/models/pegasus/test_modeling_pegasus.py

@@ -18,7 +18,14 @@ import tempfile
 import unittest
 
 from transformers import PegasusConfig, is_torch_available
-from transformers.testing_utils import require_sentencepiece, require_tokenizers, require_torch, slow, torch_device
+from transformers.testing_utils import (
+    require_sentencepiece,
+    require_tokenizers,
+    require_torch,
+    require_torch_fp16,
+    slow,
+    torch_device,
+)
 from transformers.utils import cached_property
 
 from ...generation.test_utils import GenerationTesterMixin
@@ -280,13 +287,13 @@ class PegasusModelTest(ModelTesterMixin, GenerationTesterMixin, PipelineTesterMi
         config_and_inputs = self.model_tester.prepare_config_and_inputs_for_common()
         self.model_tester.check_encoder_decoder_model_standalone(*config_and_inputs)
 
+    @require_torch_fp16
     def test_generate_fp16(self):
         config, input_dict = self.model_tester.prepare_config_and_inputs()
         input_ids = input_dict["input_ids"]
         attention_mask = input_ids.ne(1).to(torch_device)
         model = PegasusForConditionalGeneration(config).eval().to(torch_device)
-        if torch_device == "cuda":
-            model.half()
+        model.half()
         model.generate(input_ids, attention_mask=attention_mask)
         model.generate(num_beams=4, do_sample=True, early_stopping=False, num_return_sequences=3)
 
@@ -352,6 +359,7 @@ class PegasusXSUMIntegrationTest(AbstractSeq2SeqIntegrationTest):
         return AutoModelForSeq2SeqLM.from_pretrained(self.checkpoint_name).to(torch_device)
 
     @slow
+    @require_torch_fp16
     def test_pegasus_xsum_summary(self):
         assert self.tokenizer.model_max_length == 512
         inputs = self.tokenizer(self.src_text, return_tensors="pt", truncation=True, max_length=512, padding=True).to(
@@ -362,9 +370,6 @@ class PegasusXSUMIntegrationTest(AbstractSeq2SeqIntegrationTest):
         decoded = self.tokenizer.batch_decode(translated_tokens, skip_special_tokens=True)
         assert self.tgt_text == decoded
 
-        if "cuda" not in torch_device:
-            return
-        # Demonstrate fp16 issue, Contributions welcome!
         self.model.half()
         translated_tokens_fp16 = self.model.generate(**inputs, max_length=10)
         decoded_fp16 = self.tokenizer.batch_decode(translated_tokens_fp16, skip_special_tokens=True)