fix error when filter value not found in items set (#130)

* fix error when filter value not found in items set

* added conjunction false test

* add test for single non existing value

Author: aurelienroux

src/helpers.js

@@ -39,7 +39,7 @@ const combination_indexes = function(facets, filters) {
         const filter_val = disjunctive_filter[1];
 
         filter_keys.push(filter_key);
-        facet_union = facet_union.new_union(facets['bits_data'][filter_key][filter_val]);
+        facet_union = facet_union.new_union(facets['bits_data'][filter_key][filter_val] || new FastBitSet([]));
         indexes[filter_key] = facet_union;
       });
     }
@@ -311,7 +311,7 @@ const facets_ids = function(facets_data, filters) {
     filters.forEach(filter => {
 
       ++i;
-      output = output.new_union(facets_data[field][filter]);
+      output = output.new_union(facets_data[field][filter] || new FastBitSet([]));
     });
   });
 

tests/searchSpec.js

@@ -1,6 +1,7 @@
 'use strict';
 
 const assert = require('assert');
+const { clone } = require('lodash');
 const items = require('./fixtures/items.json');
 const movies = require('./fixtures/movies.json');
 let itemsjs = require('./../src/index')();
@@ -195,6 +196,60 @@ describe('search', function() {
     done();
   });
 
+  it('makes search with non existing filter value with conjunction true should return no results', function test(done) {
+
+    const itemsjs = require('./../index')(items, configuration);
+    
+    const result = itemsjs.search({
+      filters: {
+        category: ['drama', 'thriller']
+      }
+    });
+    
+    assert.equal(result.data.items.length, 0);
+    assert.equal(result.data.aggregations.tags.buckets[0].doc_count, 0);
+    
+    done();
+  });
+  
+  it('makes search with non existing filter value with conjunction false should return results', function test(done) {
+    
+    const localConfiguration = clone(configuration);
+    localConfiguration.aggregations.category.conjunction = false;
+
+    const itemsjs = require('./../index')(items, localConfiguration);
+
+    const result = itemsjs.search({
+      filters: {
+        category: ['drama', 'thriller']
+      }
+    });
+
+    assert.equal(result.data.items.length, 2);
+    assert.equal(result.data.aggregations.tags.buckets[0].doc_count, 2);
+
+    done();
+  });
+
+  it('makes search with non existing single filter value with conjunction false should return no results', function test(done) {
+    
+    const localConfiguration = clone(configuration);
+    localConfiguration.aggregations.category.conjunction = false;
+
+    const itemsjs = require('./../index')(items, configuration);
+
+    const result = itemsjs.search({
+      filters: {
+        category: ['thriller']
+      }
+    });
+
+    assert.equal(result.data.items.length, 0);
+    assert.equal(result.data.aggregations.tags.buckets[0].doc_count, 0);
+
+    done();
+  });
+
   it('throws an error if name does not exist', function test(done) {
 
     const itemsjs = require('./../index')(items, {