[JavaScript] Correct handling for older browsers and missing casing

javascript/atoms/test/attribute_typescript_test.html

@@ -55,8 +55,8 @@
       assertAttributeEquals(assert, null, byId('checky'), 'never_there');
     });
 
-    QUnit.test('should return null for missing class attribute', function (assert) {
-      assertAttributeEquals(assert, null, byId('no-class'), 'class');
+    QUnit.test('should return empty string for element with no class attribute', function (assert) {
+      assertAttributeEquals(assert, '', byId('no-class'), 'class');
     });
 
     QUnit.test('should return an empty string when attribute value is empty', function (assert) {

javascript/atoms/typescript/get-attribute.ts

@@ -21,6 +21,7 @@
    * correct property name.
    */
   const PROPERTY_ALIASES: Record<string, string> = {
+    'class': 'className',
     'readonly': 'readOnly',
   };
 
@@ -178,9 +179,9 @@
       return String(getProperty(element, name));
     }
 
-    const propName = PROPERTY_ALIASES[attribute] || attribute;
+    const propName = PROPERTY_ALIASES[name] || attribute;
 
-    if (BOOLEAN_PROPERTIES.includes(name)) {
+    if (BOOLEAN_PROPERTIES.indexOf(name) !== -1) {
       const hasAttr = getAttribute(element, attribute) !== null;
       const propValue = getProperty(element, propName);
       return hasAttr || !!propValue ? 'true' : null;

py/test/selenium/webdriver/common/element_attribute_tests.py

@@ -166,6 +166,12 @@ def test_should_return_value_of_class_attribute_of_an_element(driver, pages):
     assert "header" == classname
 
 
+def test_should_return_empty_string_for_class_attribute_when_no_class_set(driver, pages):
+    pages.load("simpleTest.html")
+    element = driver.find_element(By.ID, "oneline")
+    assert "" == element.get_attribute("class")
+
+
 # Disabled due to issues with Frames
 # def test_should_return_value_of_class_attribute_of_an_element_after_switching_iframe(driver, pages):
 #    pages.load("iframes.html")