Translated kernel menu javascript test to selenium

notebook/templates/notebook.html

@@ -255,8 +255,8 @@
                         </li>
                     </ul>
                 </li>
-                <li class="dropdown"><a href="#" class="dropdown-toggle" data-toggle="dropdown">{% trans %}Kernel{% endtrans %}</a>
-                    <ul id="kernel_menu" class="dropdown-menu">
+                <li class="dropdown"><a href="#" class="dropdown-toggle" data-toggle="dropdown" id="kernellink">{% trans %}Kernel{% endtrans %}</a>
+                    <ul id="kernel_menu" class="dropdown-menu" aria-labelledby="kernellink">
                         <li id="int_kernel"
                             title="{% trans %}Send Keyboard Interrupt (CTRL-C) to the Kernel{% endtrans %}">
                             <a href="#">{% trans %}Interrupt{% endtrans %}</a>

notebook/tests/selenium/conftest.py

@@ -118,4 +118,6 @@ def authenticated_browser(selenium_driver, notebook_server):
 
 @pytest.fixture
 def notebook(authenticated_browser):
-    return Notebook.new_notebook(authenticated_browser)
+    tree_wh = authenticated_browser.current_window_handle
+    yield Notebook.new_notebook(authenticated_browser)
+    authenticated_browser.switch_to.window(tree_wh)

notebook/tests/selenium/test_kernel_menu.py

@@ -0,0 +1,60 @@
+from selenium.common.exceptions import TimeoutException
+from selenium.webdriver.common.by import By
+from selenium.webdriver.support import expected_conditions as EC
+from selenium.webdriver.support.ui import WebDriverWait
+from notebook.tests.selenium.utils import wait_for_selector
+
+restart_selectors = [
+    '#restart_kernel', '#restart_clear_output', '#restart_run_all'
+]
+notify_interaction = '#notification_kernel > span'
+
+shutdown_selector = '#shutdown_kernel'
+confirm_selector = '.btn-danger'
+cancel_selector = ".modal-footer button:first-of-type"
+
+
+def test_cancel_restart_or_shutdown(notebook):
+    """Click each of the restart options, then cancel the confirmation dialog"""
+    browser = notebook.browser
+    kernel_menu = browser.find_element_by_id('kernellink')
+
+    for menu_item in restart_selectors + [shutdown_selector]:
+        kernel_menu.click()
+        wait_for_selector(browser, menu_item, visible=True, single=True).click()
+        wait_for_selector(browser, cancel_selector, visible=True, single=True).click()
+        WebDriverWait(browser, 3).until(
+            EC.invisibility_of_element((By.CSS_SELECTOR, '.modal-backdrop'))
+        )
+        assert notebook.is_kernel_running()
+
+
+def test_menu_items(notebook):
+    browser = notebook.browser
+    kernel_menu = browser.find_element_by_id('kernellink')
+
+    for menu_item in restart_selectors:
+        # Shutdown
+        kernel_menu.click()
+        wait_for_selector(browser, shutdown_selector, visible=True, single=True).click()
+
+        # Confirm shutdown
+        wait_for_selector(browser, confirm_selector, visible=True, single=True).click()
+
+        WebDriverWait(browser, 3).until(
+            lambda b: not notebook.is_kernel_running(),
+            message="Kernel did not shut down as expected"
+        )
+
+        # Restart
+        # Selenium can't click the menu while a modal dialog is fading out
+        WebDriverWait(browser, 3).until(
+            EC.invisibility_of_element((By.CSS_SELECTOR, '.modal-backdrop'))
+        )
+        kernel_menu.click()
+
+        wait_for_selector(browser, menu_item, visible=True, single=True).click()
+        WebDriverWait(browser, 10).until(
+            lambda b: notebook.is_kernel_running(),
+            message="Restart (%r) after shutdown did not start kernel" % menu_item
+        )