fix: user faster method if sorting by smallest set

src/database/mongo/sorted/intersect.js

@@ -76,17 +76,19 @@ module.exports = function (module) {
 
 	async function intersectSingle(params) {
 		const objects = module.client.collection('objects');
+		const sortSet = params.sets[params.weights.indexOf(1)];
+		if (sortSet === params.counts.smallestSet) {
+			return await intersectBatch(params);
+		}
+
 		let items = await objects.find({ _key: params.counts.smallestSet }, {
 			projection: { _id: 0, value: 1 },
 		}).toArray();
-		const sortSet = params.sets[params.weights.indexOf(1)];
-		const otherSets = params.sets.filter(s => s !== params.counts.smallestSet);
 		const project = { _id: 0, value: 1 };
 		if (params.withScores) {
 			project.score = 1;
 		}
-
-		if (sortSet !== params.counts.smallestSet) {
+		const otherSets = params.sets.filter(s => s !== params.counts.smallestSet);
 		// move sortSet to the end of array
 		otherSets.push(otherSets.splice(otherSets.indexOf(sortSet), 1)[0]);
 		for (let i = 0; i < otherSets.length; i++) {
@@ -100,24 +102,6 @@ module.exports = function (module) {
 			}
 			items = await cursor.toArray();
 		}
-		} else {
-			for (let i = 0; i < otherSets.length; i++) {
-				/* eslint-disable no-await-in-loop */
-				items = await module.client.collection('objects').find({
-					_key: otherSets[i], value: { $in: items.map(i => i.value) },
-				}, { projection: { _id: 0, value: 1 } }).toArray();
-			}
-			if (!items.length) {
-				return [];
-			}
-			items = await objects.find({ _key: sortSet, value: { $in: items.map(i => i.value) } })
-				.project(project)
-				.sort({ score: params.sort })
-				.skip(params.start)
-				.limit(params.limit)
-				.toArray();
-		}
-
 		if (!params.withScores) {
 			items = items.map(i => i.value);
 		}