Update metrics/bleu.py

metrics/bleu.py

@@ -15,7 +15,10 @@ def compute_bleu(
 ):
     references_per_prediction = len(references[0])
     if any(len(refs) != references_per_prediction for refs in references):
-        raise ValueError("Sacrebleu requires the same number of references for each prediction")
+        max_references_per_prediction = max(len(refs) for refs in references)
+        for refs in references:
+            refs.extend([None] * (max_references_per_prediction - len(refs)))
+
     transformed_references = [[refs[i] for refs in references] for i in range(references_per_prediction)]
     output = scb.corpus_bleu(
         predictions,