12. Testing with UniTest

Coming soon

This chapter is an outline. The full draft ships in a follow-up PR.

What this chapter will cover

Tests in a Uni codebase favor the real implementation with narrow substitutions, rather than deep mocking. This chapter covers the shape of a UniTest suite and how Design makes substitutions clean.

Concepts introduced:

• The UniTest base class and the assertion vocabulary (shouldBe, shouldContain, shouldMatch).
• Why the project avoids mocks, and what to do instead: narrow overrides via Design and in-process fakes.
• Property-based testing primitives.
• Async tests with Rx and Future.
• Cross-platform tests: writing one suite that runs under JVM, Scala.js, and Scala Native.
• Speed: keeping a Uni test suite under a second, and why that matters.

Reference you can read now

• UniTest (module reference)

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