Pert 11 Software Testing Techniques

7/27/2019 Pert 11 Software Testing Techniques

1/24

These courseware materials are to be used in conjunction with Software Engineering: A Practitioners Approach, 5/e and areprovided with permission by R.S. Pressman & Associates, Inc., copyright 1996, 2001

Chapter 17Software Testing Techniques


2/24


Software Testing

Testing is the process of exercising aprogram with the specific intent of finding

errors prior to delivery to the end user.


3/24


Testability

Operabilityit operates cleanly

Observability

the results of each test case arereadily observed

Controllabilitythe degree to which testing canbe automated and optimized

Decomposabilitytesting can be targeted

Simplicityreduce complex architecture andlogic to simplify tests

Stability

few changes are requested duringtesting

Understandabilityof the design


4/24


Operabilitas

Semakin baik dia bekerja, semakin efisien dia

dapat diujiSistem mpy bug menambah analisis dan

biaya pelaporan ke proses pengujian

Tidak ada bug yang memblok eksekusipengujian

Produk berkembang di tahap fungsional(memungkinkan pengembangan dan

pengujian secara simultan)


5/24


Observabilitas

Apa yang anda lihat adalah apa yang anda uji

Output yang berbeda dikeluarkan olehmasing2 input

Tahap dan variabel sistem dpat

dilihat/diantrikan selama eksekusiOutput yang tidak benar dapat diidentifikasi

dengan mudah

Kesalahan internal dilaporkan scr otomatis

Kode sumber dapat diakses


6/24


What Testing Shows

errors

requirements conformance

performance

an indicationof quality


7/24


Who Tests the Software?

developer independent tester

Understands the system

but, will test "gently"

and, is driven by "delivery"

Must learn about the system,

but, will attempt to break it

and, is driven by quality


8/24


Exhaustive Testing

loop < 20 X

There are 10 possible paths! If we execute onetest per millisecond, it would take 3,170 years totest this program!!

14


9/24


Selective Testing

loop < 20 X

Selected path


10/24


Test Case Design

"Bugs lurk in cornersand congregate atboundaries ..."

Bo ris Beizer

OBJECTIVE

CRITERIA

CONSTRAINT

to uncover errors

in a complete manner

with a minimum of effort and time


11/24


White-Box Testing

... our goal is to ensure that allstatements and conditions have

been executed at least once ...


12/24


Why Cover?

logic errors and incorrect assumptionsare inversely proportional to a path'sexecution probability

we often believe that a path is notlikely to be executed; in fact, reality isoften counter intuitive

typographical errors are random; it'slikely that untested paths will containsome


13/24


Basis Path Testing

First, we compute the cyclomaticcomplexity:

number of simple decisions + 1

or

number of enclosed areas + 1

In this case, V(G) = 4


14/24


Cyclomatic Complexity

A number of industry studies have indicatedthat the higher V(G), the higher the probabilityor errors.

V(G)

modules

modules in this range are

more error prone


15/24


Basis Path TestingNext, we derive theindependent paths:

Since V(G) = 4,there are four paths

Path 1: 1,2,3,6,7,8

Path 2: 1,2,3,5,7,8Path 3: 1,2,4,7,8Path 4: 1,2,4,7,2,4,...7,8

Finally, we derive testcases to exercise thesepaths.

1

2

34

5 6

7

8


16/24


Basis Path Testing Notes

you don't need a flow chart,but the picture will help whenyou trace program paths

count each simple logical test,

compound tests count as 2 ormore

basis path testing should beapplied to critical modules


17/24


Loop Testing

NestedLoops

ConcatenatedLoops UnstructuredLoops

Simpleloop


18/24


Loop Testing: Simple Loops

Min imum cond i t ions

Simple Loop s

1. skip the loop entirely

2. only one pass through the loop

3. two passes through the loop

4. m passes through the loop m < n5. (n-1), n, and (n+1) passes throughthe loop

where n is the maximum number

of allowable passes


19/24


Loop Testing: Nested Loops

Start at the innermost loop. Set all outer loops to theirminimum iteration parameter values.

Test the min+1, typical, max-1 and max for theinnermost loop, while holding the outer loops at theirminimum values.

Move out one loop and set it up as in step 2, holding all

other loops at typical values. Continue this step untilthe outermost loop has been tested.

If the loops are independent of one anotherthen treat each as a simple loopelse* treat as nested loops

endif*for example, the f inal loop co un ter value of loop 1 isused to ini t ia l ize loop 2.

Nested L oop s

Concatenated Loops


20/24


Black-Box Testing

requirements

eventsinput

output

Black Bo Testing


21/24


Black Box Testing

Menemukan kesalahan dalam kategori:Fungsi-fungsi yang tidak benar/hilang

Kesalahan interface

Kesalahan struktur data/akses databaseeksternal

Kesalahan kinerja

Inisialisasi dan kesalahan transmisi

Black Box Testing


22/24


Black Box Testing

Pengujian didesain untuk menjawab pertanyan2

berikut: Bagaimana validitas fungsional diuji?

Kelas input apa yang akan membuat test casemenjadi baik?

Apakah sistem sangat sensitif terhadap nilai inputtertentu?

Bagaimana batasan dari suatu data diisolasi

Kecepatan data apa dan volume data apa yangdapat ditolerir oleh sistem?

Apa pengaruh kombinasi tertentu dari dataterhadap operasi sistem?

Pengujian untuk Aplikasi


23/24


Pengujian untuk Aplikasidan Lingkungan Khusus

Pengujian GUI

Pengujian Arsitektur Client/Server

Pengujian Dokumentasi dan Fasilitas Help

Pengujian Sistem Real Time

Equivalence Partitioning:


24/24


Equivalence Partitioning:Sample Equivalence

Classes

user supplied commands

responses to system prompts

file namescomputational data

physical parameters

bounding valuesinitiation valuesoutput data formattingresponses to error messagesgraphical data (e.g., mouse picks)

data outside bounds of the programphysically impossible data

proper value supplied in wrong place

Valid d ata

Inval id data

Date post:	14-Apr-2018
Category:	Documents
Upload:	lim-cia-chien
View:	225 times
Download:	0 times

Pert 11 Software Testing Techniques

Documents