Don't allow empty string or None for email.

openedx/core/djangoapps/user_api/accounts/api.py

@@ -114,8 +114,9 @@ def update_account_settings(requesting_user, update, username=None):
 
     # If user has requested to change email, we must call the multi-step process to handle this.
     # It is not handled by the serializer (which considers email to be read-only).
-    new_email = None
+    changing_email = False
     if "email" in update:
+        changing_email = True
         new_email = update["email"]
         del update["email"]
 
@@ -148,7 +149,7 @@ def update_account_settings(requesting_user, update, username=None):
         field_errors = _add_serializer_errors(update, serializer, field_errors)
 
     # If the user asked to change email, validate it.
-    if new_email:
+    if changing_email:
         try:
             validate_new_email(existing_user, new_email)
         except ValueError as err:
@@ -186,7 +187,7 @@ def update_account_settings(requesting_user, update, username=None):
         )
 
     # And try to send the email change request if necessary.
-    if new_email:
+    if changing_email:
         try:
             do_email_change_request(existing_user, new_email)
         except ValueError as err:

openedx/core/djangoapps/user_api/accounts/tests/test_views.py

@@ -438,8 +438,20 @@ class TestAccountAPI(UserAPITestCase):
         get_response = self.send_get(client)
         self.assertEqual(new_email, get_response.data["email"])
 
-        # Finally, try changing to an invalid email just to make sure error messages are appropriately returned.
-        error_response = self.send_patch(client, {"email": "not_an_email"}, expected_status=400)
+    @ddt.data(
+        ("not_an_email",),
+        ("",),
+        (None,),
+    )
+    @ddt.unpack
+    def test_patch_invalid_email(self, bad_email):
+        """
+        Test a few error cases for email validation (full test coverage lives with do_email_change_request).
+        """
+        client = self.login_client("client", "user")
+
+        # Try changing to an invalid email to make sure error messages are appropriately returned.
+        error_response = self.send_patch(client, {"email": bad_email}, expected_status=400)
         field_errors = error_response.data["field_errors"]
         self.assertEqual(
             "Error thrown from validate_new_email: 'Valid e-mail address required.'",