refactor app directory structure and add tests

tests/node_modules/nightwatch/lib/api/assertions/attributeEquals.js

@@ -0,0 +1,57 @@
+/**
+ * Checks if the given attribute of an element has the expected value.
+ *
+ * ```
+ *    this.demoTest = function (client) {
+ *      browser.assert.attributeEquals('body', 'data-attr', 'some value');
+ *    };
+ * ```
+ *
+ * @method attributeEquals
+ * @param {string} selector The selector (CSS / Xpath) used to locate the element.
+ * @param {string} attribute The attribute name
+ * @param {string} expected The expected value of the attribute to check.
+ * @param {string} [message] Optional log message to display in the output. If missing, one is displayed by default.
+ * @api assertions
+ */
+
+var util = require('util');
+exports.assertion = function(selector, attribute, expected, msg) {
+  var DEFAULT_MSG = 'Testing if attribute %s of <%s> equals "%s".';
+  var MSG_ELEMENT_NOT_FOUND = DEFAULT_MSG + ' ' + 'Element could not be located.';
+  var MSG_ATTR_NOT_FOUND = DEFAULT_MSG + ' ' + 'Element does not have a ' + attribute + ' attribute.';
+
+  this.message = msg || util.format(DEFAULT_MSG, attribute, selector, expected);
+
+  this.expected = function() {
+    return expected;
+  };
+
+  this.pass = function(value) {
+    return value === expected;
+  };
+
+  this.failure = function(result) {
+    var failed = (result === false) ||
+      // no such element
+      result && (result.status === -1 || result.value === null);
+
+    if (failed) {
+      var defaultMsg = MSG_ELEMENT_NOT_FOUND;
+      if (result && result.value === null) {
+        defaultMsg = MSG_ATTR_NOT_FOUND;
+      }
+      this.message = msg || util.format(defaultMsg, attribute, selector, expected);
+    }
+    return failed;
+  };
+
+  this.value = function(result) {
+    return result.value;
+  };
+
+  this.command = function(callback) {
+    return this.api.getAttribute(selector, attribute, callback);
+  };
+
+};