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News, Insights about Visual Regression Testing from Diffy's team

There are dozens of reasons why you might need to change your web hosting provider. Too much downtime, overgrowing your current provider, the need for more bandwidth -- are just a few of them. We’ve heard them and many others from Diffy clients. But we heard them in a different context. 

Much of the modern Web is powered by open source content management systems (CMS) like WordPress or Drupal. Like all software, though, even the most reliable CMS needs bugfixes, and all world-class software gets new features in time. And sometimes, – we’ve all been there – no matter how good the intentions behind them are, some updates break things.
A lot web pages right now have some elements that gets activated by clicking on the pages. For example, sliders, or dropdown menu, or tabs. How to take screenshots of those pages too?

The biggest pain point of fulll-page screenshot visual regression testing are false positives. They usually happen because of the dynamic nature of the content.

There are few ways of handling this situation.

First, you could mask or remove dynamic elements completely. But then you’ll miss testing them.

Another option, if you are comparing your Production with Staging environment you could sync the content so those dynamic elements are the same.

But what if you take screenshots from Production regularly and editors do change content over time?

Because both Patternlab and Drupal 8 can use twig as a rendering engine it is possible to build a theme to be based on Patternlab’s components. It makes very easy to apply visual regression testing to Patternlab’s demo site.