2009/9/17 Schif Schaf said:
What's the difference between WebDriver and Selenium?
Selenium runs in a browser, and uses JavaScript to perform all your
automated actions. It need a browser running to work. Several are
supported, Firefox, Safari, IE and I think others. You are at thier
mercy of the browser's JavaScript engine - I've often had trouble with
IE's XPath support, for instance - tests will run fine in Firefox and
safari, but not work in IE.
One big advantage of Selenium is that there an "IDE" available, a
Firefox add-on which will allow you to record actions. This is useful
for building regression tests and acceptance tests for bugs. Sadly, it
often tempts people into writing their acceptance tests after the
fact, too - a grave mistake IMHO.
Selenium tests can be written in Python, Ruby, Java, and in the form
of HTML tables. This last seems quite popular with QAs for some reason
which escapes me entirely.
WebDriver runs outside a browser. It can be (and usually is) used to
drive a real browser, though there's is a HtmlUnit driver available,
which bypasses any real browser and goes direct to the site you are
testing. Even this last option, though, does allow the testing of
sites which make use of JavaScript - which is just about all of them
these days.
It makes use of native drivers for each of the browsers it supports,
so it runs very much faster than Selenium. Since it presents the test
program with its own version of the page's DOM tree, it's also less
likely to give browser incompatibilities.
WebDriver tests can be written in Java or Python, at the moment.
The Selenium people have recognized the superiority of the WebDriver
approach, so the nascent Selenium 2 will use WebDriver under the
covers. For the moment, though, you have to pick one or the other.
Mechanize is a superb library for its intended purpose - I use it all
the time. It's lack of support for pages with JavaScript
functionality, though, means it's not very useful at a testing tool
for modern web sites.
