WEB102: Let loose the browsers!!!

So you're aware some cross-browser testing is required, and marketing have come back to you with an extensive list ... they'd like you to test,

• IE 11 (when available), 10, 9, 8, 7
• Chrome the last three versions
• Firefox the last two versions
• Safari just the latest version
• Opera just the latest version

Cool - let testing commence!  Only ... it's not that simple.  There are some tools out there which will let you compare different versions of the same browser, and whilst better than nothing, they don't give you a full feel.

The most obvious issue is generally a computer has just a single version of a browser on your machine.  If you upgrade IE 10 to 11, it removes your version of IE 10!

Likewise things get complicated because IE 7 (for instance) doesn't easily install on a Windows 8 machine, and needs a lot of trickery to get working.  Likewise running IE 11 on an XP machine is never going to happen.  For all these things, the situation created by hacking the system to make it work is likely going to invalidate and erode some of your assumptions for your test.

It's not surprising then in such an environment, the idea of doing browser testing by installing different versions of browser then stripping them off your machine is non-too-popular.

What has taken off to aid browser compatibility are virtual machines.  A virtual machine allows you to emulate another (obviously less powerful) computer within your own.  It's run from a file which sets up everything about the machine, and means you can use your Windows 8 machine, but pretend to be a Windows 7, XP or (shudder) Vista machine.  It's also heaps cheaper (but not as much fun) as having a whole suite of reference machines of different build.  But then again, you can have dozens of them set up differently, running on one machine (though not concurrently obviously ... as "performance may vary").  If you have Apple hardware, you can pretend to be a Windows machine (but alas not the other way around).

Each virtual machine is a file which can be shared amongst testers (providing they have similar machines), and each one can be set up with the appropriate platform and browsers you want to test on.

This means once your suite is set up, all you need to do is run up the machine you want - no continuous install/uninstall.  You just keep and share a library of the machines, and boot up the one you need.  No needing multiple machines.  Another tester I was talking to told me with virtual machines, as long as you keep backups, you can try out crazy things and almost trash the machines trying different things (including editing registry settings), because you can just return to the original (unmodified) backup so easily if you really get into trouble.  It means you can test not just on different browsers, but represent different platforms as well.

Some of the most popular virtual machine tools at the moment belong to VMWare.  Check them out.

Obviously virtual machines aren't easy to set up, and need some tech buy in and support.  However they're an increasingly popular method of having different browsers and machines "to hand" when testing.