Foundations of Software Testing: Fundamental Algorithms and Techniques

Test Generation

As an example, suppose that p

c

: a < b + c and p

i

: a > b + c.

Consider a test set

T

= {

t

1

,

t

2

}, where

t

1

:<

a

=0,

b

=0,

c

=0> and

t

2

:< a = 0, b = 1, c = 1 >. The fault in p

i

is not revealed by t

1

as both

p

c

and p

i

evaluate to false when evaluated against t

1

. However, the

fault is revealed by the test case t

2

as p

c

evaluates to true and p

i

to

false when evaluated against t

2

.

2.7.2.1 Missing or Extra Boolean Variable Faults

Two additional types of common faults have not been considered in the

fault model described above. These are the missing Boolean variable and

the extra Boolean variable faults.

As an illustration, consider a process-control system in which the

pressure P and temperature T of a liquid container is being measured

and transmitted to a contr ...