Should I write tests that directly display input to output or dynamically generate a result?

Question

Old manual programmer, new for writing test cases (shame for me I know).

It seems to me that there are two ways to write test cases:

• Match fixed inputs with fixed outputs and claim that they match
• Generated cards or fixed inputs for dynamic outputs and claim to match

---

# Static testing:
assert_equal "test".upcase, "TEST"

# Dynamic testing:
assert_equal person.full_name, "#{person.title} #{person.first_name} #{person.last_name}"

---

Of course, there are pros and cons to each approach. Duplication of implementation details is erroneous, but allows me to generate data samples and run tests on it. Hard coding values ​​make the correct conclusion very explicit, but do not seem to allow code reuse.

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Answer 1

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Answer 2

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