Test Driven DevelopmentDesigning Test Cases

Haarlem Software Developer Meetup

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KvK 53479335

Lichtfabriekplein 1, 2031 TE Haarlem

P.O. Box 2031 , 2002 CA Haarlem

+31 (0)88 248 1632, info@ximedes.com

www.ximedes.com

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Meetup Sponsor:

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Why do we test?Why do we automate tests?What are good tests?

01-10-2015 Confidential Page 6Build Confidence and Create Trust

Why do we have tests?

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Why do we automate tests?

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What are good tests?

http://stackoverflow.com/questions/61400/what-makes-a-good-unit-test

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Intent:

Tests should express what we expect the code to do. Tests should be readable.

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Independent

The success ot failure of a test should not depend on anything other then the production code.

The order of the tests. The system running the tests.

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Repeatable

Tests should produce the same results each time..every time.Tests should not rely on uncontrollable params.

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Clean Code

SRP: Each test should test just one thing DRY: Any given behavior should specified in

one and only one test NAME: Tests should have proper names. Tests should not have side effect

Single Responsibility PrincipleDon’t Repeat Yourself

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1. Arrange2. Act3. Assert

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Given the numbers 3 and 4When I multiply those numberThen the result should be 12

Given the numbers 6 and 8When I multiply those numberThen the result should be 48

Specification by Example

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Use ‘personas’ express expectations

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Arrange:Given Joris is a member of the HSDM

Act:When Marco publishes a newly scheduled Meetup

Assert:Then Joris should receive a Notification about the event

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1. You are here to LEARN. (and have fun)

2. Try to do your best.

3. Work in pairs.Find a partner in a similar programming language and operating system

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Write a system to help the umpire keep track of the score of a single Game.

The umpire inputs which player won a pointThe systems output is: The current score within the game.

Example:• Player one scores a point Score: 15-0• Player one scores a point Score: 30-0• Player two scores a point Score: 30-15

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A game is won by the first player to have won at least four points in total and at least two points more than the opponent. The score is then “Win for player1” or “Win for player2”

The running score of each game is described in a manner peculiar to tennis: scores from zero to three points are described as “Love”, “Fifteen”, “Thirty”, and “Forty” respectively.

If at least three points have been scored by each player, and the scores are equal, the score is “Deuce”.

If at least three points have been scored by each side and a player has one more point than his opponent, the score of the game is “Advantage player1” or “Advantage player2”.

See you next time: February 16thTest Driven Development

Designing Testable (Clean) code Haarlem Software Developer Meetup