Test Generation from Requirements
number of tests can be reduced significantly if the GUI prevents invalid
inputs from getting into the application under test.
Note that the tests derived in the boiler example make the assump-
tion that the GUI has been correctly implemented and does prohibit
incorrect values from entering the control software.
2.4 BOUNDARY-VALUE ANALYSIS
Experience indicates that programmers make mistakes in processing
values at and near the boundaries of equivalence classes. For example,
suppose that method M is required to compute a function f
1
when the
condition x ≤ 0 is satisfied by input x and function f
2
otherwise. How-
ever, M has an error due to which it computes f
1
for x < 0 and f
2
other-
wise. Obviously, this fault is revealed, though ...