Testing for unforseen visual change

Your computer can (probably) see better than you

Paul Stanton
Oct 21, 2016 · 5 min read
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We start again, with a button.

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Remember me?
btn btn--primary btn--outline btn--small btn--disabled
btn btn--disabled btn--outline btn--small btn--primary
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Just one of many button grids

Wraith is that annoying colleague who hovers over your shoulder and points out the tiniest difference, but only when you ask it to, which is nice.

Shall we play a game?

Here’s two screenshots of that button grid but I’ve made a change, can you see it? Try not to scroll down too much until you’ve had a good look…

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Stop scrolling, can you tell what it is yet?

Figured it out yet?

I can’t tell, but Wraith can.

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Wraith: “What the f… m8??”
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Gallery of Fails

Spend time setting up a safety net

If you work on a design system, however large, spending time learning and setting up a tool like Wraith will reduce the amount of time you spend manually checking your components every time you make a change, and it’ll let you release with more confidence that unintended changes haven’t leaked out to other components.

No-one likes leaky styles

We don’t use visual regression testing to fail builds, but it’s becoming an extremely valuable safety net to run before committing changes or performing a release of our design system. We’ve all had issues where a change with CSS is one place affects other components in ways we weren’t expecting, and Wraith helps us catch those.


The product design team at Jadu

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