Summary

Vera's contracts already define what each function requires and guarantees. The three-tier verification system already classifies which properties are proved (Tier 1) vs runtime-checked (Tier 3). A vera test command would close the loop by automatically exercising Tier 3 contracts with generated inputs.

Motivation

In traditional development, tests are a separate artefact maintained alongside code. In Vera, contracts ARE the specification — requires() defines the valid input space, ensures() defines expected behavior. Test management should fall out of the language design, not be bolted on.

What this enables

• Property-based test generation — requires() clauses define the input space; the compiler generates valid inputs automatically and checks ensures() at runtime
• Automatic coverage reporting — vera verify already reports Tier 1 (proved) vs Tier 3 (runtime) counts; vera test would exercise the Tier 3 contracts
• No separate test files for contract-covered properties — the contracts are the tests

Possible future extensions

• Cross-function scenario testing (call A then B then C, check end-to-end properties)
• Mutation testing (change the implementation, see if any contract breaks)
• Shrinking (minimize failing inputs, as in QuickCheck/Hypothesis)

Relationship to existing work

• Contracts and verification are complete (C4/C6)
• Runtime contract insertion is working (Tier 3 checks compile to WASM)
• vera verify --json already provides the tier breakdown (tier1_verified, tier3_runtime, total)

Roadmap

Fits naturally into C8 (end-to-end) or as a standalone phase.