fix(core): recursively merge arrays in searchParameters

fixes #80

lib/InstantSearch.js

@@ -3,6 +3,7 @@ var algoliasearchHelper = require('algoliasearch-helper');
 
 var forEach = require('lodash/collection/forEach');
 var merge = require('lodash/object/merge');
+var union = require('lodash/array/union');
 
 class InstantSearch {
   constructor(applicationID, searchKey, indexName, searchParameters) {
@@ -19,7 +20,16 @@ class InstantSearch {
     // Get the helper configuration from the widget
     if (widgetDefinition.getConfiguration) {
       var partialConfiguration = widgetDefinition.getConfiguration(this.searchParameters);
-      this.searchParameters = merge({}, this.searchParameters, partialConfiguration);
+      this.searchParameters = merge(
+        {},
+        this.searchParameters,
+        partialConfiguration,
+        (a, b) => {
+          if (Array.isArray(a)) {
+            return union(a, b);
+          }
+        }
+      );
     }
     // Add the widget to the list of widget
     this.widgets.push(widgetDefinition);

package.json

@@ -8,9 +8,9 @@
     "lint": "./scripts/lint.sh",
     "build": "./scripts/build.sh",
     "dev": "./scripts/dev.sh",
-    "test": "babel-node test/*.js && npm run lint",
-    "test:watch": "nodemon -i node_modules/ -i coverage/ -i .git/ -i dist/ -q --exec 'babel-node test/*.js | tap-spec'",
-    "test:coverage": "babel-node node_modules/.bin/isparta cover test/*.js",
+    "test": "./scripts/test.sh && npm run lint",
+    "test:watch": "nodemon -i node_modules/ -i coverage/ -i .git/ -i dist/ -q --exec './scripts/test.sh | tap-spec'",
+    "test:coverage": "babel-node node_modules/.bin/isparta cover ./scripts/test.sh",
     "doctoc": "doctoc --maxlevel 3 README.md"
   },
   "browserify": {
@@ -25,6 +25,7 @@
     "babel": "5.8.23",
     "babel-eslint": "4.1.1",
     "babel-loader": "5.3.2",
+    "babel-tape-runner": "1.2.0",
     "css-loader": "0.16.0",
     "doctoc": "0.15.0",
     "eslint": "1.3.1",

scripts/test.sh

@@ -0,0 +1,7 @@
+#!/usr/bin/env bash
+
+set -e # exit when error
+
+printf "\nTest\n"
+
+babel-tape-runner test/**/*.js

test/InstantSearch.js → test/InstantSearch/lifecycle.js

@@ -1,6 +1,6 @@
 var test = require('tape');
 
-test('InstantSearch', function(t) {
+test('InstantSearch: lifecycle', function(t) {
   var EventEmitter = require('events').EventEmitter;
 
   var proxyquire = require('proxyquire');
@@ -18,7 +18,7 @@ test('InstantSearch', function(t) {
 
   var appId = 'appId';
   var apiKey = 'apiKey';
-  var indexName = 'test';
+  var indexName = 'lifeycle';
 
   var searchParameters = {some: 'configuration', another: {config: 'parameter'}};
 
@@ -28,7 +28,7 @@ test('InstantSearch', function(t) {
     render: sinon.spy()
   };
 
-  var InstantSearch = proxyquire('../lib/InstantSearch', {
+  var InstantSearch = proxyquire('../../lib/InstantSearch', {
     algoliasearch: algoliasearch,
     'algoliasearch-helper': algoliasearchHelper
   });

test/InstantSearch/recursively-merge-arrays-searchParameters.js

@@ -0,0 +1,66 @@
+var test = require('tape');
+
+test('InstantSearch: recursively merge arrays in searchParameters', function(t) {
+  var EventEmitter = require('events').EventEmitter;
+
+  var proxyquire = require('proxyquire');
+  var sinon = require('sinon');
+
+  // simple mocks
+  var helper = new EventEmitter();
+  helper.search = noop;
+
+  // hijack `algoliasearch` and `algoliasearchHelper` modules
+  var algoliasearch = noop;
+  var algoliasearchHelper = sinon.stub().returns(helper);
+
+  var searchParameters = {
+    some: ['value', 'another value'],
+    cool: 3,
+    another: {nested: ['array', 'of', 'values']}
+  };
+
+  var firstWidget = {
+    getConfiguration: sinon.stub().returns({
+      first: ['values'],
+      some: ['first'],
+      another: {yes: true}
+    })
+  };
+
+  var secondWidget = {
+    getConfiguration: sinon.stub().returns({
+      first: ['new value'],
+      cool: 4,
+      another: {nested: ['thing'], yes: false},
+      some: ['second']
+    })
+  };
+
+  var InstantSearch = proxyquire('../../lib/InstantSearch', {
+    algoliasearch: algoliasearch,
+    'algoliasearch-helper': algoliasearchHelper
+  });
+
+  var search = new InstantSearch('appId', 'apiKey', 'recursively', searchParameters);
+
+  search.addWidget(firstWidget);
+  search.addWidget(secondWidget);
+  search.start();
+
+  var expected = {
+    first: ['values', 'new value'],
+    some: ['value', 'another value', 'first', 'second'],
+    cool: 4,
+    another: {nested: ['array', 'of', 'values', 'thing'], yes: false}
+  };
+
+  t.deepEqual(
+    algoliasearchHelper.args[0][2],
+    expected
+  );
+
+  t.end();
+});
+
+function noop() {}