audience_evaluator: Continue with evaluation even when no user

attributes are passed in

Author: Matt Carroll

packages/optimizely-sdk/lib/core/audience_evaluator/index.js

@@ -20,8 +20,9 @@ module.exports = {
    * Determine if the given user attributes satisfy the given audience conditions
    * @param  {Object[]} audiences            Audiences to match the user attributes against
    * @param  {Object[]} audiences.conditions Audience conditions to match the user attributes against
-   * @param  {Object}   userAttributes       Hash representing user attributes which will be used in determining if
-   *                                         the audience conditions are met
+   * @param  {Object}   [userAttributes]     Hash representing user attributes which will be used in
+   *                                         determining if the audience conditions are met. If not
+   *                                         provided, defaults to an empty object.
    * @return {Boolean}  True if the user attributes match the given audience conditions
    */
   evaluate: function(audiences, userAttributes) {
@@ -30,9 +31,8 @@ module.exports = {
       return true;
     }
 
-    // if no user attributes specified, return false
     if (!userAttributes) {
-      return false;
+      userAttributes = {};
     }
 
     for (var i = 0; i < audiences.length; i++) {

packages/optimizely-sdk/lib/core/audience_evaluator/index.tests.js

@@ -18,10 +18,18 @@ var chai = require('chai');
 var assert = chai.assert;
 
 var chromeUserAudience = {
-  conditions: ['and', {'name': 'browser_type', 'value': 'chrome'}],
+  conditions: ['and', {
+    name: 'browser_type',
+    value: 'chrome',
+    type: 'custom_attribute',
+  }],
 };
 var iphoneUserAudience = {
-  conditions: ['and', {'name': 'device_model', 'value': 'iphone'}],
+  conditions: ['and', {
+    name: 'device_model',
+    value: 'iphone',
+    type: 'custom_attribute',
+  }],
 };
 
 describe('lib/core/audience_evaluator', function() {
@@ -72,6 +80,18 @@ describe('lib/core/audience_evaluator', function() {
         assert.isFalse(audienceEvaluator.evaluate([chromeUserAudience, iphoneUserAudience], safariUsers));
         assert.isFalse(audienceEvaluator.evaluate([chromeUserAudience, iphoneUserAudience], nexusSafariUsers));
       });
+
+      it('should return true if no attributes are passed and the audience conditions evaluate to true in the absence of attributes', function() {
+        var conditionsPassingWithNoAttrs = ['not', {
+          match: 'exists',
+          name: 'input_value',
+          type: 'custom_attribute',
+        }];
+        var audience = {
+          conditions: conditionsPassingWithNoAttrs,
+        };
+        assert.isTrue(audienceEvaluator.evaluate([audience]));
+      });
     });
   });
 });