Selenium python find element by class name stopped working from v 2 2 to 2 21 not able to use Compound Class Name

Question

I am using Selenium's python library to scrape data from an HTML page in Firefox. I have had to update from Selenium 2.0 to 2.21 because the server has updated Firefox.

In Version 2.21 calls to find_element_by_class_name("grid-cell-inner grid-col-name") fails with:

selenium.common.exceptions.WebDriverException: Message: u'Compound class names not permitted'

The class name of the element I am trying to access is grid-cell-inner grid-col-name

The call to find_element_by_class_name() worked in Version 2.2, so the logic is correct, and the data used to be found OK. Something changed in Version 2.21.

All the Selenium examples give simple examples with class name foo etc, and none with the type of name I need to access.

Why Selenium stopped supporting the finding classes with names like grid-cell inner grid-col-name, and what is the solution?

Kindly let me know how to find elements with "compound" class names?

Answer 1

The problem about WebDriver is that it still evolves. A lot. I personally don't know about a version that supported searching by many classes in one command, so it must have been a fairly old one :).

Searching by a CSS selector should work, however:

find_element_by_css_selector(".grid-cell-inner.grid-col-name");

I don't recommend using XPath for this particular thing, because these two following expressions are a different thing:

//*[class='grid-cell-inner grid-col-name']

//*[class='grid-col-name grid-cell-inner']