How to name our Unit Tests

Connection - 10'

Imagine we want to test this method :

public static boolean isLeapYear(int year)

Here are the

How would you name your first test ?

Ask attendees to note on a Sticky Note what is the name of their first test
Compare the different styles
What do they prefer (Dot voting)

Concepts - 10'

Tests names v1

yearsNotDivisibleBy4...
yearsDivisibleBy4ButNotBy100...
yearsDivisibleBy100ButNotBy400...
yearsNotDivisibleBy400...

Is it readable ?
What is the intent ?

Tests names v2

years_not_divisible_by_4...
years_divisible_by_4_but_not_by_100...
years_divisible_by_100_but_not_by_400...
years_not_divisible_by_400...

Is it more readable ?
What is the intent ?

Tests names v3

years_not_divisible_by_4_are_not_leap_years
years_divisible_by_4_but_not_by_100_are_leap_years
years_divisible_by_100_but_not_by_400_are_not_leap_years
years_not_divisible_by_400_are_not_leap_years

Intent is more clear, isn’t it ?

Tests names v4

public class Leap_year_spec {
    public static class A_year_is_a_leap_year {
        @Test public void if_it_is_divisible_by_4_but_not_by_100()...
        @Test public void if_it_is_divisible_by_400()...
    }
    
    public static class A_year_is_not_a_leap_year {
        @Test public void if_it_is_not_divisible_by_4()...
        @Test public void if_it_is_divisible_by_100_but_not_by_400()...
    }
}

Express what the class should be able to do
Read it as a full sentence : express a true business specification
You should avoid technical terms

Concrete Practice - 30'

Extract the Test Cases you want to write
- Define the structure and naming of your tests

Conclusion - 10'

Imagine you use this naming technique during the next 6 months :

What has changed ?
Who else have noticed those changes ?
What are the impacts on your day to day ?

Resources

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Last updated 4 years ago

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