Page 213 - DCAP405_SOFTWARE_ENGINEERING

Software Engineering

Notes exceeds its maximum. This is called robustness testing. We may also include test cases to check
what happens when more than one variable have maximum values. This is called worst case
analysis.

What is ad-hoc testing?
Did u know?
Using prior testing knowledge and experience to test similar programs is called ad-hoc
testing.

Equivalence Class Testing

In this method of testing, input domain of a program is divided into a finite number of equivalence
classes such that the test of a representative value of each class is equivalent to a test of any other
value. That is if a test in a class detects one error all other test cases belonging to the same class
must detect the same error. Also, if a test case in a class did not detect an error the other test cases
of the same class also should not detect the error. This method of testing is implemented using
the following two steps:
1. The equivalence class is identified by taking each input condition and dividing it into
valid and invalid classes.
2. Developing test cases using the classes identified. This is done by writing test cases covering
all the valid equivalence classes and a single case for invalid equivalence class.

Again good test cases will be those that check for boundary value condition.

Decision Table based Testing

Decision tables are useful for describing situations in which a number of combinations of
actions are taken under varying sets of conditions. There are four parts of a decision table
namely, Condition stub, Action stub, Condition entries and Action entries. These are described
in Figure 12.6.

Figure 12.6: Decision Table Terminology
Condition Stub Entry
C1 True False
C2
True False True False
C3
True False True False True False -
Action Stub
A1 X X X
A2 X X X
A3 X X
A4
X X X

To develop test cases from decision tables, we treat conditions as input and actions as outputs.
Sometimes conditions end up referring to equivalence classes of inputs, and actions refers to
major functional processing portions of the item being tested.

Cause Effect Graphing Technique

One drawback of boundary value analysis and equivalence partitioning is that these they do not
explore combinations of input circumstances which may result in interesting conditions. These

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