Strictly check the number of placeholder tokens

Signed-off-by: DarkLight1337 <[email protected]>

vllm/multimodal/processing.py

@@ -1128,18 +1128,20 @@ def get_dummy_data(
         prompt_token_ids = mm_inputs["prompt_token_ids"]
         placeholders_by_modality = mm_inputs["mm_placeholders"]
 
-        total_placeholders_by_modality = dict[str, int]()
-        for modality, placeholders in placeholders_by_modality.items():
-            num_placeholders = sum(item["length"] for item in placeholders)
-            max_tokens = mm_max_tokens[modality]
-
-            if num_placeholders != max_tokens:
-                logger.warning(
-                    "The processed dummy data has a total of %d placeholder "
-                    "tokens for the '%s' modality, which is not the expected "
-                    "%d tokens.", num_placeholders, modality, max_tokens)
-
-            total_placeholders_by_modality[modality] = num_placeholders
+        total_placeholders_by_modality = {
+            modality: sum(item["length"] for item in placeholders)
+            for modality, placeholders in placeholders_by_modality.items()
+        }
+        expected_placeholders_by_modality = {
+            modality: mm_max_tokens[modality]
+            for modality in placeholders_by_modality
+        }
+        if total_placeholders_by_modality != expected_placeholders_by_modality:
+            raise AssertionError(
+                f"The processed dummy data has a total of "
+                f"{total_placeholders_by_modality} placeholder tokens, which "
+                f"is not the expected {expected_placeholders_by_modality} "
+                "tokens.")
 
         total_len = len(prompt_token_ids)
         if total_len > seq_len: