The Benefits of Automation and Tools

A project-level pie chart shows how many bugs were found in each major functional area of the software.

If you're testing a particular feature that means you may need to run your tests not once, but potentially dozens of times. You'll check that the bugs you found in previous test runs were indeed fixed and that no new bugs were introduced. This process of rerunning your tests is known as regression testing.

If a small software project had several thousand test cases to run, there might be barely enough time to execute them just once. Running them numerous times might be impossible, let alone monotonous. Software test tools and automation can help solve this problem by providing a more efficient means to run your tests than by manual testing.

The principal attributes of tools and automation are:

· Speed. Think about how long it would take you to manually try a few thousand test cases for the Windows Calculator. You might average a test case every five seconds or so. Automation might be able to run 10, 100, even 1000 times that fast.

· Efficiency. While you're busy running test cases, you can't be doing anything else. If you have a test tool that reduces the time it takes for you to run your tests, you have more time for test planning and thinking up new tests.

· Accuracy and Precision. After trying a few hundred cases, your attention span will wane and you'll start to make mistakes. A test tool will perform the same test and check the results perfectly, each and every time.

· Resource Reduction. Sometimes it can be physically impossible to perform a certain test case. The number of people or the amount of equipment required to create the test condition could be prohibitive. A test tool can be used to simulate the real world and greatly reduce the physical resources necessary to perform the testing.

· Simulation and Emulation. Test tools are often used to replace hardware or software that would normally interface to your product. This "fake" device or application can then be used to drive or respond to your software in ways that you choose and ways that might otherwise be difficult to achieve.

· Relentlessness. Test tools and automation never tire or give up. They're like that battery-operated bunny of the TV commercials they can keep going and going and…

All this probably sounds like great news. You could have test tools do all the work for you turn them loose and wait for the results. Unfortunately, it's not that easy. Houses aren't built automatically, even though carpenters have power saws and nail guns. The tools just make it easier for them to do their work and for the resulting work to be of higher quality. Software test tools operate the same way.

NOTE:

Software test tools aren't a substitute for software testers they just help software testers perform their jobs better.

It's important to note that using test tools isn't always the right answer. Sometimes there's no substitute for manual testing. For now, take in the information about what tests tools can do and how they work. Think about how you might use them to complement your testing tasks. At the end of this chapter, you'll learn about a few limitations and cautions to consider before you embark on using tools on your projects.