Error - Element not found
One of perhaps the most common and direct error messages one will see, especially when starting out with writing automation scripts, will be the
Element not found error. A variety of root causes including wrong selectors, missing waits, navigation problems and more can hide behind it.
Example error message:
UnhandledPromiseRejectionWarning: Error: No node found for selector: ...
- Obvious possible cause #1: the selector is wrong. See working with selectors.
- Obvious possible cause #2: the element is not on the page and the automation tool is not automatically waiting for it to appear. An explicit wait might fix the problem.
- Not-so-obvious possible cause: the click on the previous element did not actually go through. From the perspective of our automation tool, everything went fine, but from ours what happened is more similar to a silent failure. We are now looking for the right element but are on the wrong page (or the page is in the wrong state), and the target element is therefore not found.
How to avoid confusion
Either walk through the execution in headful mode or take screenshots before and after the instruction that has raised the error - this will help you verify whether the application state actually is the one you expect.
Note that this list neither is nor aims to be complete: additional possible causes most likely exist for this error.