Information Technology Reference
In-Depth Information
Quality
Assurance
Product
Testing
QA is throughout the life cycle, testing is after the product is ready
Figure 12.1 Quality assurance (QA) versus testing.
. Testing involves exercising the soft-
ware under controlled conditions with an aim toward finding defects
before a version is “accepted,” or before the customers detect such defects.
This stress on testing in the software industry is akin to treating a patient
once a disease has manifested itself, rather than trying to prevent the
initial infection.
testing is oriented toward
detection
If programmers are responsible for thoroughly testing
their code, the question naturally arises, “Are program-
mers and testers not duplicating each other's efforts?”
Perhaps they do here and there but when programmers
test code, they test it from the inside and move out.
Testers start from the outside and move in.
… The combination of approaches works because pro-
grammers focus on code while testers focus on fea-
tures. With the two working from opposite directions,
the chances of finding unknown bugs are increased.
—From
Writing Solid Code
, Steve Maguire
In any process, there are intermediate products that come before the
final product releases. These intermediate products, such as requirements
documents, data models, build documents, and infrastructure specifica-
tions, are artifacts with their own quality requirements. If the quality of
the output is influenced by the quality of the input, then resources should
be devoted to quality procedures related to the input, rather than con-
centrating on the output. The way organizations separate functions drives
certain perceptions of responsibility within the organization. If there is a
