context.preProcess();
int topLevelDocId = result.docIdAndVersion().docId + result.docIdAndVersion().context.docBase;
Explanation explanation = context.searcher().explain(context.query(), topLevelDocId);
for (RescoreSearchContext ctx : context.rescore()) {
Rescorer rescorer = ctx.rescorer();
explanation = rescorer.explain(topLevelDocId, context, ctx, explanation);
}
if (request.fields() != null || (request.fetchSourceContext() != null && request.fetchSourceContext().fetchSource())) {
// Advantage is that we're not opening a second searcher to retrieve the _source. Also
// because we are working in the same searcher in engineGetResult we can be sure that a
// doc isn't deleted between the initial get and this call.