def copy_fields_to_request(self, review_request):
        """Copies the draft information to the review request and updates the
        draft's change description.
        """
        def update_list(a, b, name, record_changes=True, name_field=None):
            aset = set([x.id for x in a.all()])
            bset = set([x.id for x in b.all()])

            if aset.symmetric_difference(bset):
                if record_changes and self.changedesc:
                    self.changedesc.record_field_change(name, a.all(), b.all(),
                                                        name_field)

                a.clear()
                for item in b.all():
                    a.add(item)

        for field_cls in get_review_request_fields():
            field = field_cls(review_request)

            if field.can_record_change_entry:
                old_value = field.load_value(review_request)
                new_value = field.load_value(self)

                if field.has_value_changed(old_value, new_value):
                    field.save_value(new_value)

                    if self.changedesc:
                        field.record_change_entry(self.changedesc,
                                                  old_value, new_value)

        # Screenshots are a bit special.  The list of associated screenshots
        # can change, but so can captions within each screenshot.
        screenshots = list(self.screenshots.all())
        caption_changes = {}

        for s in review_request.screenshots.all():
            if s in screenshots and s.caption != s.draft_caption:
                caption_changes[s.id] = {
                    'old': (s.caption,),
                    'new': (s.draft_caption,),
                }

                s.caption = s.draft_caption
                s.save(update_fields=['caption'])

        # Now scan through again and set the caption correctly for newly-added
        # screenshots by copying the draft_caption over. We don't need to
        # include this in the changedescs here because it's a new screenshot,
        # and update_list will record the newly-added item.
        for s in screenshots:
            if s.caption != s.draft_caption:
                s.caption = s.draft_caption
                s.save(update_fields=['caption'])

        if caption_changes and self.changedesc:
            self.changedesc.fields_changed['screenshot_captions'] = \
                caption_changes

        update_list(review_request.screenshots, self.screenshots,
                    'screenshots', name_field="caption")

        # There's no change notification required for this field.
        review_request.inactive_screenshots = self.inactive_screenshots.all()

        # Files are treated like screenshots. The list of files can
        # change, but so can captions within each file.
        files = list(self.file_attachments.all())
        caption_changes = {}

        for f in review_request.file_attachments.all():
            if f in files and f.caption != f.draft_caption:
                caption_changes[f.id] = {
                    'old': (f.caption,),
                    'new': (f.draft_caption,),
                }

                f.caption = f.draft_caption
                f.save(update_fields=['caption'])

        # Now scan through again and set the caption correctly for newly-added
        # files by copying the draft_caption over. We don't need to include
        # this in the changedescs here because it's a new screenshot, and
        # update_list will record the newly-added item.
        for f in files:
            if f.caption != f.draft_caption:
                f.caption = f.draft_caption
                f.save(update_fields=['caption'])

        if caption_changes and self.changedesc:
            self.changedesc.fields_changed['file_captions'] = caption_changes

        update_list(review_request.file_attachments, self.file_attachments,
                    'files', name_field="display_name")

        # There's no change notification required for this field.
        review_request.inactive_file_attachments = \
            self.inactive_file_attachments.all()
dataset/ETHPy150Open reviewboard/reviewboard/reviewboard/reviews/models/review_request_draft.py/ReviewRequestDraft.copy_fields_to_request/original