UPDATE to this post, April 18th, 2015: for purposes of automated testing, I'd like to define "check" as a specialization or subclass of "test" where the verifications are limited to those specifically coded or otherwise determined in advance. The usefulness of "check" is limited to what people also call "automated test," and has a business justification that it avoids confusion and risk: it avoids the confusion that a manual test involving a GUI or web page, once automated, obviates the need for a human to run the manual test, and it avoids the quality and business risk that would result from losing the corresponding measurements of product quality.
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It’s time to retire the phrase “automated testing.”
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It’s time to retire the phrase “automated testing.”
Given that software testing is about measuring,
communicating and promoting quality, leadership often sees automation – that
is, making a software product do things automatically –as a way of doing all of
the above faster. Unfortunately, it
does not work that way.
People are smart, but computers and computing power are not smart. People running user stories
or test cases or doing exploratory testing are very good at finding large
numbers of bugs, within the limits of attention, getting tired or bored, etc.
People are great at spotting things that are not as they should be, e.g., a
flicker in an icon over here or a misalignment of a table over there, or a
problem of discoverability.
When automated product testing is done well, it has huge
value: it is excellent at regressing product quality issues quickly,
repeatedly, and tirelessly. Automation does not get tired or bored. Computers
are very good at processing numbers and repeating procedures, and doing them
fast and reliably, and at e.g. 3AM local time when your people are home
sleeping.
However, automation is not
good at finding product bugs or anomalous issues like a flickering icon. You
need good human testers for that.
Instead of “automated testing,” it’s time to use a term
proposed by James Bach and Michael Bolton (see their post http://www.satisfice.com/blog/archives/856
) to define automation that drives tests: Checking. A single automated
procedure that measures a defined aspect of quality for the SUT is a “check.”
The term “check” applies where more commonly a professional in the space might
use the term “automated test” but since testing is an intelligent activity done
by humans, the term “automated test” becomes an oxymoron; once a test is
automated, it is no longer a test in the same sense. If done well, it is fast,
reliable, tireless and highly repeatable, but the value is very different from
the same procedure run by a testing professional.
A skilled and experienced tester running a manual test can discover, characterize
and describe as a bug any of a broad range of issues. The range of potential
issues found has few limits, and is driven by the intelligence, creativity and
observational skill of the tester. However, to take that manual test, automate
it, and then run it offline (without human observation or intervention) or in
the lab, severely restricts the discoverable range of issues. Automated tests
are capable of flagging issues that block the procedure of the test, and issues
that are the topic of explicit verifications or metrics coded into the test or
automated test harness, but they do not measure anything else about the
product. The automated test will usually run faster than the manual test, and a
well-written automated test will run more reliably and repetitively than the
manual test, but it does not replace the manual test. If the automated test
taken from the manual test above runs and passes a thousand times, running the
manual version of the test once could
still find important issues.
The team therefore still needs the manual test, and in the
context of measuring product quality, there is benefit to tracking the manual
test and the manual test results separately from the automated test and the
automation results. The manual and the automated version of the test both have
their values for quality, and one does not replace the other.
It’s time for the industry to use “check” because this term
emphasizes that automating a test is
not the same as running the test faster and does not obviate the manual version of the test. The need for manual testers will always be
there for the team; however, a well-designed and frequently-run set of checks
can make manual testing faster, more effective, and more fun because it makes
for less manual repetition of measurements that are verified by automation and
more exploration around the manual test.
In addition, the best-written manual tests are significantly
different from ideal checks. Manual (or quasi-manual) tests tend to focus on
scenarios or mini-scenarios, because that is the natural usage for end-users,
and it gives testers the most opportunities to find issues and characterize
them as bugs to be considered by the team. Checks focus on specific
verifications, and ideally are as short as possible.
“Check” means that that the verifications are strictly
limited to what is specified in advance, either by the coded-in verifications,
verifications for the test group (if that is implemented) or by the test
harness as a whole. In the context of automated testing, this specification
might be specified in prose, but is always specified in the code that is
written. This works very well for an automated test, because it is important to
be completely consistent over test runs with what is and is not verified about
the SUT.
This post is based on an excerpt from Matt Griscom’s
forthcoming book, MetaAutomation.
Maybe if we ban the word testing entirely we can avoid all the problems created by it.
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