black box testing should make use of randomly generated inputs (only a
test range should be specified by the tester), to eliminate any guess work
by the tester as to the methods of the function
data outside of the specified input range should be tested to check the
robustness of the program
boundary cases should be tested (top and bottom of specified range) to
make sure the highest and lowest allowable inputs produce proper output
the number zero should be tested when numerical data is to be input
stress testing should be performed (try to overload the program with
inputs to see where it reaches its maximum capacity), especially with real
time systems
crash testing should be performed to see what it takes to bring the
system down
test monitoring tools should be used whenever possible to track which
tests have already been performed and the outputs of these tests to avoid
repetition and to aid in the software maintenance
other functional testing techniques include: transaction testing, syntax
testing, domain testing, logic testing, and state testing.
finite state machine models can be used as a guide to design functional
tests
According to Beizer the following is a general order by which tests
should be designed:
Clean tests against requirements.
Additional structural tests for branch coverage, as needed.
Additional tests for data-flow coverage as needed.
Domain tests not covered by the above.
Special techniques as appropriate--syntax, loop, state, etc.
