Functional Testing - Software Testing: Testing Across the Entire Software Development Life Cycle - page 115

value analysis results would then be the set of values ( 1, 0, 1, 49, 50, 51, 98, 99,

and 100).
In the case of admission co-pay, the beginning boundary test co-pay would

be epsilon around the beginning value

$ 0.00. The ending boundary test co-pay would be $999.99, $1000.00, and $1,000.01,
which are

$0.01, $0.00, and $0.01, which are /

epsilon around the ending value $1000.00. The midvalue epsilon
test values would be $499.99, $500.00, and $500.01. The resulting equivalence
class with boundary value analysis results would then be the set of values (

/

$0.01,
$0.00, $0.01, 0.99, $1.00, $1.99, $10.00, $10.99, $100.00, $100.99, $499.99, $500.00,
$500.01, $999.00, $999.99, $1000.00, and $1000.01).
The result of a boundary value analysis is additional input test values to the
equivalence class of values to specifi cally exercise the application's behavior where
that behavior tends to fail most often. Even with the additional boundary test values,
the equivalence classes remain signifi cantly smaller than the set of all possible val-
ues for the input under consideration.
Equivalence classes of inputs with boundary values are executed as one of the
fi rst step in black box testing. Once correct input value acceptance has be verifi ed,
you can begin to verify correct output results.

7.6.3 Expected Results Coverage Technique

While equivalence classes and boundary value analysis focus on input test values,
expected results coverage focuses on output test values for associated input values.
The fi rst step is to fi nd the business rules in the application requirements that defi ne
the expected results. We will use our hospital admission example to demonstrate
what kind of business rules might be found in the requirements documentation.
Presented with an admission age and a co-pay, the application under test must de-
termine the maximum daily hospital room rate for hospital room assignment. The
maximum room rate insurance coverage business rules might look like the table
below.

Business rules for maximum room rate insurance coverage

Output/
result Input Input

Age on
admission

Maximum
room rate

Co-pay

0-6 years
7-17 years
18-35 years
36-49 years
50-74 years
75-99 years

$50.00
$75.00
$100.00
$125.00
$200.00
$250.00

$50.00
$100.00
$150.00
$300.00
$350.00
$400.00