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IN 3240 Software Testing

Seminar 01

Test-Driven Development

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Part 1: Let’s talk

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TDD:

- What is your understanding of it?

- Where did you hear about it?

- How do you see its use?

- Have you searched on th internet for learning sources?

- What others say about TDD: https://www.youtube.com/watch?v=a6oP24CSdUg

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Image: https://blog.hubstaff.com

Why are we really practicing TDD?

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TDD means writing unit tests firstThe principles of unit tests = F.I.R.S.TUnit tests differ from other tests - they must be F.I.R.S.T.

•Fast: No database connections. In memory•Isolatable/Independent: Tests should not depend on each other•Repeatable: Tests must not depend on external factors•Self-Describing: Each test just returns a boolean result for pass or fail. Youshould not output to find out whether it worked or not.•Timely: Write them before the code

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Unit test frameworks- Usually third party products- Simpify the process of unit testing- It is possible to write unit tests without the support of such a framework

(assertion, exception handling)

Have you heard of unit test frameworks for C#?

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Part 2: Let’s read

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What is this test about? What is the production code supposed to do?

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What are these asserts about? What is the production code supposed to do?

Check Stackoverflow for asserts examples:

https://stackoverflow.com/questions/3241105/java-junit-asserttrue-vs-assertfalse

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Part 3: Let’s practice

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Exercise:

We take two examples from the Code Dojo and try to reproduce theTDD techniques.

You will choose one and work in a group. You will just have to repeatthe training material in the video. We discuss it after 30 minues.

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https://cyber-dojo.org/

Prime factors:Factorize a positive integer number into its prime factors.For example:

2 -> [2]3 -> [3]4 -> [2,2]6 -> [2,3]9 -> [3,3]12 -> [2,2,3]15 -> [3,5]

JavaScript + CucumberVideo to reproduce: https://www.youtube.com/watch?v=9XhlRgCad60&t=208s

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https://cyber-dojo.org/

Fizz buzz :Write a program that prints the numbers from 1 to 100. But for multiples ofthree print "Fizz" instead of the number and for the multiples of five print"Buzz". For numbers which are multiples of both three and five, print"FizzBuzz".

Sample output:12Fizz4BuzzFizz78FizzBuzz... etc up to 100JavaScript + Jasmine Video to reproduce: https://www.youtube.com/watch?v=UBrhwDBvgOA

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Discuss

What other information did you find on the internet?

Where did you stumble?

How was yout TDD experience so far?

Remember: • these examples are more complex than the unit tests you will have to

write at work. • Use the many sources of training. Start with videos. Then,

stackoverflow.• Two people to follow: Robert Cecil Martin (Uncle Bob); Roy Osherove

– find their webpages and read about TDD. Watch their videos, expecially the ones debating TDD.