What is a test case in unit testing?

Updated May 6, 2026

Short answer

A test case is a set of conditions to verify a specific behavior of code.

Deep explanation

A test case defines input, execution steps, and expected output. It ensures a specific functionality behaves correctly under defined conditions.

Real-world example

Testing password validation rules in a signup form.

Common mistakes

  • Writing unclear or overly broad test cases.

Follow-up questions

  • What makes a good test case?
  • Can test cases depend on each other?

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