feat(recommend): filter out input objectIDs [RECO-2436]

packages/algoliasearch-helper/src/algoliasearch.helper.js

@@ -1922,6 +1922,7 @@ AlgoliaSearchHelper.prototype._dispatchRecommendResponse = function (
     }
     cache[id] = Object.assign({}, firstResult, {
       hits: sortAndMergeRecommendations(
+        ids,
         indices.map(function (idx) {
           return content.results[idx].hits;
         })

packages/algoliasearch-helper/src/utils/sortAndMergeRecommendations.js

@@ -21,11 +21,13 @@ function getAverageIndices(indexTracker, nrOfObjs) {
   });
 }
 
-function sortAndMergeRecommendations(results) {
+function sortAndMergeRecommendations(objectIDs, results) {
   var indexTracker = {};
 
   results.forEach(function (hits) {
     hits.forEach(function (hit, index) {
+      if (objectIDs.includes(hit.objectID)) return;
+
       if (!indexTracker[hit.objectID]) {
         indexTracker[hit.objectID] = { indexSum: index, count: 1 };
       } else {

packages/algoliasearch-helper/test/spec/utils/sortAndMergeRecommendations.js

@@ -79,6 +79,7 @@ var response = {
 
 test('sorts the items based on their average index thus preserving applied rules', () => {
   const result = sortAndMergeRecommendations(
+    ['X', 'Y', 'Z'],
     response.results.map(function (res) {
       return res.hits;
     })
@@ -124,3 +125,37 @@ test('sorts the items based on their average index thus preserving applied rules
       ]
     `);
 });
+
+test('filters out input objectIDs', () => {
+  const result = sortAndMergeRecommendations(
+    ['A', 'B', 'C'],
+    response.results.map(function (res) {
+      return res.hits;
+    })
+  );
+
+  expect(result).toMatchInlineSnapshot(`
+      Array [
+        Object {
+          "_score": 76,
+          "name": "Product E",
+          "objectID": "E",
+        },
+        Object {
+          "_score": 100,
+          "name": "Product F",
+          "objectID": "F",
+        },
+        Object {
+          "_score": 96,
+          "name": "Product G",
+          "objectID": "G",
+        },
+        Object {
+          "_score": 89,
+          "name": "Product D",
+          "objectID": "D",
+        },
+      ]
+    `);
+});