c23e2307b9b2e0147ef4699b2b5bbabdac08a0fc,parlai/core/torch_generator_agent.py,TreeSearch,advance,#TreeSearch#Any#,888

Before Change

        // beam blocking
        if self.block_ngram > 0:
            for beam_id, hyp in enumerate(self.partial_hyps):
                if len(hyp) < self.block_ngram - 1:
                    continue
                ngrams = self._find_ngrams(hyp, self.block_ngram)
                prefix = hyp[-(self.block_ngram - 1) :]
                for ngram in ngrams:
                    if prefix == list(ngram[:-1]) or self.block_ngram == 1:
                        logprobs[beam_id][ngram[-1]] = neginf(logprobs.dtype)

        hyp_ids, tok_ids, self.scores = self.select_paths(logprobs, self.scores)
        // use clone() here to ensure that self.all_scores will not be changed
        // later due to any penalties to self.scores
        self.all_scores.append(self.scores.clone())

After Change

        if self.block_ngram > 0:
            logprobs = self._block_ngrams(self.block_ngram, logprobs, None)

        if self.context_block_ngram > 0:
            if self.context is None:
                raise ValueError(
                    "Must use TreeSearch.set_context to use context blocking."
                )
            logprobs = self._block_ngrams(
                self.context_block_ngram, logprobs, self.context
            )

        hyp_ids, tok_ids, self.scores = self.select_paths(logprobs, self.scores)
        // use clone() here to ensure that self.all_scores will not be changed
        // later due to any penalties to self.scores
        self.all_scores.append(self.scores.clone())

Instances