TechTalks #1TechTalks #1

Unit Testing and Test-Driven Development

Duong Trong Tantandt@fpt.com.vnHanoi, 9- 2011

Objectives

0 Why testing?

0 Introduction to unit testing

0 Unit testing in Java with JUnit

0 What is Test-Driven Development?

0 How can TDD improve quality?

0 TDD practices and guidelines.

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CRISIS

Numbers:4.4 million cars recalledBillions of $ loss.Damage the brand

Desire vs. Reality

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Requirement\Design

Desired

Implementation

Reality

testing

gap

Why testing?

0 Ensuring QUALITY

0 Managing RISKS

0 Optimizing Return-On-Investment (ROI)

0 Professionalism

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Typical Production model

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Bug cost

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Balancing

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GOOD

FASTCHEAP

Testing level0 Unit testing

0 On individual unit of source code (function, class, etc.)0 Smallest testable part0 Developer testing

0 Integration testing0 On groups of modules

0 System testing0 On complete integrated system

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JUnit

0 Unit testing automation framework for Java

0 Can do integration test

0 Integrated in IDEs (Eclipse, NetBeans, IntelliJ, etc.)

0 Must have tool for Java developers

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http://www.junit.org/

Test-Driven Development0 You don’t start programming until you have designed

your tests!0 Strategy

0 Make it Fail0No code without a failing test

0 Make it Work0As simply as possible

0 Make it Better0Refactor(code, design, test, documentation)

0 Believe in testing

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Suggested TDD

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Thinking changed

0 Design or code must be TESTABLE

0 “Error Message” is a good news

0 Courage

0 Simple

0 Agile

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How to do TDD0 Design

0 Use [simple] design , figure out what to do0 [Then .. create the skeleton first]

0 Test0 Write test that reflect the design0 All tests should FAIL

0 Implement0 Write the code

0 Test0 All tests should PASS

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TDD live demo

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0 Application: simplified Calculator

0 Language: Java0 Tools used:

0 NetBeans 70 JUnit0 Task board (Excel)0 Whiteboard (for simple

design)

Red-Green-Blue model

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Refactor to Clean Code

0Readable

0Maintainable

0Changeable

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Acceptance Test-Driven Development

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RequirementAutomated Acceptance

Tests TDD

Definition Of

Done

ATDD: team collaboration, a kind of cross-functionality

Acceptance TDD (ATDD)

3D strategy0 Discuss in requirement workshop

0 To make tests library0 Develop in concurrence

0 To create more Passed features0 Deliver for acceptance

0 To meet DONE definition, accepted by users

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Supporting system: CI

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Q&A

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Further reading

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Tools0 JUnit: http://junit.org 0 FitNesse: http://fitnesse.org/ 0 RoBotFramework: http://code.google.com/p/

robotframework/ 0 Hudson CI: http://hudson-ci.org/ 0 SVN: http://subversion.tigris.org/

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Thank you!

Meet Tấn DT:

•TechTalks•HanoiScrum.net•Slideshare.net/duongtrongtan•Facebook: Duong Trong Tan•tandt@fpt.edu.vn