Testing · Senior · Question 16 of 75

Which are the main sources of non-determinism in tests, according to Fowler?

✓Correct answer: Lack of isolation, asynchronous behaviour, remote services, time and resource leaks
2TypeScript and ESLint
3Using too many assertions

Explanation

For each one there is a fix: isolate data, wait for conditions, replace remote services with doubles, control the clock.

Further reading

Martin Fowler: Eradicating Non-Determinism in Tests ↗

Test yourself

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