What is a test runner?

Updated May 6, 2026

Short answer

A test runner executes test cases and reports results.

Deep explanation

Test runners manage execution order, setup environments, and generate reports. Examples include Jest CLI and Mocha.

Real-world example

Running CI pipelines that execute test suites automatically.

Common mistakes

  • Confusing test runner with framework.

Follow-up questions

  • Can tests run in parallel?
  • Why use a test runner?

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