ASSIGNMENT $2$

Purpose

This assignment is aimed at helping you understand how the white box testing method known as control flow testing works. You should have read section $3\mathrm{.}3\mathrm{.}2$ of the text book before attempting this assignment. For a more comprehensive explanation of control flow testing, please refer to the attached document.

You are required to complete the tasks described below.

Test software

The following program has been implemented for a newly proposed tax calculation formula for residents of a fictitious country.

$//$ incomeList$[]$: the array recording the individual income items

$//$ childList$[]$: the array recording the ages of children supported by this person

$//$ parentList$[]$: the array recording the ages of parents supported by this person

public double computeTax$($double$[]$ incomeList, int$[]$ parentList, int$[]$ childList$)\{$

double taxAmount $=0\mathrm{.}0$;

double incomeAmount $=0\mathrm{.}0$;

$//$ calculate the income amount

for $($int i $=0$; i $<$ incomeList.length; i$++)\{$

incomeAmount $=$ incomeAmount $+$ incomeList$[$i$]$; $6\}$

$//$ calculate the basic tax

if $($incomeAmount $<=40000)\{$

taxAmount $=$ incomeAmount $*0\mathrm{.}02$;

$\}$ else if $($incomeAmount $>40000$ && incomeAmount $<=80000)\{$

taxAmount $=800+$ incomeAmount $*0\mathrm{.}07$;

$\}$ else if $($incomeAmount $>80000$ && incomeAmount $<=120000)\{$

taxAmount $=800+2800+$ incomeAmount $*0\mathrm{.}12$;

$\}$ else if $($incomeAmount $>120000)\{$

taxAmount $=800+2800+4800+$ incomeAmount $*0\mathrm{.}17$; $15\}$

$//$ calculate the tax exemption from having children

int taxExemption $=0$;

int numOfChild $=$ childList.length;

while $($numOfChild $>0)\{$

if $($childList$[$numOfChild $-1]<18)\{$

taxAmount $=$ taxAmount $-4000$;

taxExemption $=$ taxExemption $+4000$; $22\}$

$23$ numOfChild$--$; $24\}$

$//$ calculate the tax exemption from having parents

for $($int j $=0$; j $<$ parentList.length; j$++)\{$

if $($parentList$[$j$]>60)\{$

taxAmount $=$ taxAmount $-2000$;

taxExemption $=$ taxExemption $+2000$; $29\}$

$30\}$

$//$ the maximum tax exemption is $8000$ each person

if $($taxExemption $<=8000)\{$

if $($taxAmount $>=0)\{$

return taxAmount;

$\}$ else $\{//$ i$.$e$.,$ taxAmount $<0$

return $0$; $36\}$

$\}$ else $\{//$ i$.$e$.,$ taxExemption $>8000$

taxAmount $=$ taxAmount $+($taxExemption $-8000)$;

return taxAmount;

$\}$

$\}$

Your Tasks

Design test cases to achieve the statement coverage on the function $$computeTax$($list the statements covered by each test case using the line number of each statement$).$ If it is not feasible, explain the reason. Use the minimum number of test cases to achieve the statement coverage.

For this portion, create a control flow chart diagram; identify each path with a letter, similar to figure $3\mathrm{.}2$ in the textbook. Design test cases to achieve path coverage on the function $$computeTax$."$ Identify paths covered by each test case using your notation in the diagram. If path coverage is not feasible, explain the reason. Use the minimum number of test cases to achieve the path coverage.

Design test cases to achieve loop coverage $($see below$)$ on the function $$computeTax$($list the loops covered by each test case$).$ If it is not feasible, explain the reason. Try your best to use the minimum number of test cases to achieve the loop coverage. Consider a loop covered if at least in one test the loop body was executed $0$ times, in a second test the body was executed exactly once, and in another test the body was executed more than once.

Special Instructions

For each level of coverage, provide a brief explanation of your work. This should include any assumptions you have made.

Test cases should be presented in a table with each row showing the following:

Test ID #$,$ input data, statements$/$paths$/$loops covered by the test case, expected output, actual output, pass$/$fail$,$ and $\%$ coverage. You may add additional columns to display key variables such as tax exemption.

See $$Understanding Software Test Cases$$ for tips on how test cases should be written

Code coverage should be shown by listing the statements $($using line numbers$)$ for each test case.

Your path diagram may be created with a drawing tool or NEATLY handwritten and inserted into your work.