Generate: add tests for caches with `pad_to_multiple_of` (#29462)

tests/test_cache_utils.py

@@ -291,7 +291,7 @@ class CacheIntegrationTest(unittest.TestCase):
 
     @require_torch_gpu
     @parameterized.expand(["eager", "sdpa", "flash_attention_2"])
-    def test_static_cache_greedy_sampling_pad_left(self, attn_implementation):
+    def test_static_cache_greedy_decoding_pad_left(self, attn_implementation):
         EXPECTED_GENERATION = [
             "The best color is the one that complements the skin tone of the",
             "We should not undermind the issues at hand.\nWe should not undermind the issues",
@@ -331,7 +331,7 @@ class CacheIntegrationTest(unittest.TestCase):
 
     @require_torch_gpu
     @parameterized.expand(["eager", "sdpa", "flash_attention_2"])
-    def test_static_cache_greedy_sampling_pad_right(self, attn_implementation):
+    def test_static_cache_greedy_decoding_pad_right(self, attn_implementation):
         EXPECTED_GENERATION = [
             "The best color isЋ the one that complements the skin tone of",
             "We should not undermind the issues at hand.\nWe should not undermind the issues",
@@ -382,6 +382,76 @@ class CacheIntegrationTest(unittest.TestCase):
         with self.subTest(f"{attn_implementation}, static, compiled"):
             self.assertListEqual(decoded, EXPECTED_GENERATION)
 
+    def test_dynamic_cache_extra_left_padding(self):
+        """Tests that adding extra left-padding does not affect the generation with the dynamic cache"""
+        EXPECTED_GENERATION = [
+            "The best color is the one that complements the skin tone of the",
+            "We should not undermind the issues at hand.\nWe should not undermind the issues",
+        ]
+
+        tokenizer = AutoTokenizer.from_pretrained(
+            "NousResearch/Llama-2-7b-chat-hf", padding_side="left", pad_token="<s>"
+        )
+        model = AutoModelForCausalLM.from_pretrained(
+            "NousResearch/Llama-2-7b-chat-hf",
+            torch_dtype=torch.bfloat16,
+        ).to(torch_device)
+        inputs = tokenizer(
+            ["The best color is", "We should not undermind the issues at hand"], padding=True, return_tensors="pt"
+        ).to(model.device)
+
+        gen_out = model.generate(**inputs, do_sample=False, max_new_tokens=10)
+        decoded = tokenizer.batch_decode(gen_out, skip_special_tokens=True)
+        self.assertListEqual(decoded, EXPECTED_GENERATION)
+
+        # Now with extra left-padding
+        inputs_expanded = tokenizer(
+            ["The best color is", "We should not undermind the issues at hand"],
+            padding=True,
+            return_tensors="pt",
+            pad_to_multiple_of=32,
+        ).to(model.device)
+        self.assertTrue(inputs.input_ids.shape[1] < inputs_expanded.input_ids.shape[1])
+        gen_out = model.generate(**inputs_expanded, do_sample=False, max_new_tokens=10)
+        decoded = tokenizer.batch_decode(gen_out, skip_special_tokens=True)
+        self.assertListEqual(decoded, EXPECTED_GENERATION)
+
+    def test_static_cache_extra_left_padding(self):
+        """Tests that adding extra left-padding does not affect the generation with the static cache"""
+        EXPECTED_GENERATION = [
+            "The best color is the one that complements the skin tone of the",
+            "We should not undermind the issues at hand.\nWe should not undermind the issues",
+        ]
+
+        tokenizer = AutoTokenizer.from_pretrained(
+            "NousResearch/Llama-2-7b-chat-hf", padding_side="left", pad_token="<s>"
+        )
+        model = AutoModelForCausalLM.from_pretrained(
+            "NousResearch/Llama-2-7b-chat-hf",
+            torch_dtype=torch.bfloat16,
+        ).to(torch_device)
+        inputs = tokenizer(
+            ["The best color is", "We should not undermind the issues at hand"], padding=True, return_tensors="pt"
+        ).to(model.device)
+
+        model.generation_config.cache_implementation = "static"
+
+        gen_out = model.generate(**inputs, do_sample=False, max_new_tokens=10)
+        decoded = tokenizer.batch_decode(gen_out, skip_special_tokens=True)
+        self.assertListEqual(decoded, EXPECTED_GENERATION)
+
+        # Now with extra left-padding
+        inputs_expanded = tokenizer(
+            ["The best color is", "We should not undermind the issues at hand"],
+            padding=True,
+            return_tensors="pt",
+            pad_to_multiple_of=32,
+        ).to(model.device)
+        self.assertTrue(inputs.input_ids.shape[1] < inputs_expanded.input_ids.shape[1])
+        gen_out = model.generate(**inputs_expanded, do_sample=False, max_new_tokens=10)
+        decoded = tokenizer.batch_decode(gen_out, skip_special_tokens=True)
+        self.assertListEqual(decoded, EXPECTED_GENERATION)
+
     @unittest.skip("TODO @gante static cache's does not support beam search yet")
     def test_static_cache_beam_search(self):
         pass