diff --git a/spec/services/helpers/comparator.test.js b/spec/services/helpers/comparator.test.js
new file mode 100644
index 0000000..66e26d3
--- /dev/null
+++ b/spec/services/helpers/comparator.test.js
@@ -0,0 +1,60 @@
+(function () {
+  'use strict';
+
+  describe('The xos.helper module', function(){
+    describe('The Comparator service', () => {
+
+      let service;
+
+      // load the application module
+      beforeEach(module('xos.helpers'));
+
+      // inject the cartService
+      beforeEach(inject(function (_Comparator_) {
+        // The injector unwraps the underscores (_) from around the parameter names when matching
+        service = _Comparator_;
+      }));
+
+      describe('given a string', () => {
+        it('should return true if expected is substring of actual', () => {
+          const res = service('test', 'te');
+          expect(res).toBeTruthy();
+        });
+
+        it('should return false if expected is not substring of actual', () => {
+          const res = service('test', 'ab');
+          expect(res).toBeFalsy();
+        });
+      });
+
+      describe('given a boolean', () => {
+        it('should return true if values match', () => {
+          expect(service(false, false)).toBeTruthy();
+          expect(service(true, true)).toBeTruthy();
+          expect(service(0, false)).toBeTruthy();
+          expect(service(1, true)).toBeTruthy();
+        });
+
+        it('should return false if values doesn\'t match', () => {
+          expect(service(false, true)).toBeFalsy();
+          expect(service(true, false)).toBeFalsy();
+          expect(service(1, false)).toBeFalsy();
+          expect(service(0, true)).toBeFalsy();
+        });
+      });
+
+      describe('given a number', () => {
+        // NOTE if numbers should we compare with === ??
+        it('should return true if expected is substring of actual', () => {
+          expect(service(12, 1)).toBeTruthy();
+        });
+
+        it('should return false if expected is not substring of actual', () => {
+          expect(service(12, 3)).toBeFalsy();
+        });
+      });
+
+    });
+  });
+
+})();
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