Add basic selenium test case

Author: Madhu94

notebook/static/notebook/js/notebook.js

@@ -2858,6 +2858,7 @@ define([
             $('<br/>')
         ).append(
             $('<input/>').attr('type','text').attr('size','25')
+            .attr('data-testid', 'save-as')
             .addClass('form-control')
         );
 
@@ -2894,7 +2895,8 @@ define([
                                     that.events.trigger('notebook_renamed.Notebook', data);
 
                                 },function(error) {
-                                   console.error(i18n.msg._(error.message || 'Unknown error saving notebook'));
+                                   const msg = i18n.msg._(error.message || 'Unknown error saving notebook');
+                                   $('.save-message').html(`<span style='color:red;'>${msg}</span>`);
                                 });
                         }
                         that.contents.get(nb_path, {type: 'notebook'}).then(function(data) {

notebook/tests/selenium/test_save_as_notebook.py

@@ -0,0 +1,40 @@
+from notebook.tests.selenium.utils import wait_for_selector
+from selenium.webdriver.common.keys import Keys
+from selenium.webdriver.support.ui import WebDriverWait
+
+def wait_for_rename(browser, nbname, timeout=10):
+    wait = WebDriverWait(browser, timeout)
+    def notebook_renamed(browser):
+        elem = browser.find_element_by_id('notebook_name')
+        current_name = browser.execute_script('return arguments[0].innerText', elem)
+        return current_name == nbname
+    return wait.until(notebook_renamed)
+
+def save_as(nb):
+    JS = 'Jupyter.notebook.save_notebook_as()'
+    return nb.browser.execute_script(JS)
+
+def get_notebook_name(nb):
+    JS = 'return Jupyter.notebook.notebook_name'
+    return nb.browser.execute_script(JS)
+
+def set_notebook_name(nb, name):
+    JS = 'Jupyter.notebook.rename("{}")'.format(name)
+    nb.browser.execute_script(JS)   
+
+def test_save_notebook_as(notebook):
+    # Set a name for comparison later
+    set_notebook_name(notebook, name="nb1.ipynb")
+    wait_for_rename(notebook.browser, "nb1")
+    assert get_notebook_name(notebook) == "nb1.ipynb"
+    # Wait for Save As modal, save
+    save_as(notebook)
+    wait_for_selector(notebook.browser, '.save-message')
+    inp = notebook.browser.find_element_by_xpath('//input[@data-testid="save-as"]')
+    inp.send_keys('new_notebook.ipynb')
+    inp.send_keys(Keys.RETURN)
+    wait_for_rename(notebook.browser, "new_notebook")
+    # Test that the name changed
+    assert get_notebook_name(notebook) == "new_notebook.ipynb"
+    # Test that address bar was updated (TODO: get the base url)
+    assert "new_notebook.ipynb" in notebook.browser.current_url