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testing-assertions

Testing & Quality
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Tests Phylax Credible Layer assertions with CredibleTest, fuzzing, and backtesting. Use when writing or reviewing assertion tests.

QUICK START

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Testing Assertions

Build confidence that assertions block invalid transactions and allow valid ones.

When to Use

  • Writing unit, fuzz, or backtesting tests for assertions.
  • Investigating false positives or gas-limit risks.
  • Adding regression tests after protocol or assertion changes.

When NOT to Use

  • You need help designing invariants or triggers. Use designing-assertions.
  • You only need implementation details. Use implementing-assertions.
  • You need a backtesting setup. Use backtesting-assertions.

Quick Start

  • Use CredibleTest and cl.assertion(...) to register a single assertion function for the next transaction.
  • cl.assertion(...) is consumed by the next external call and still requires a matching trigger.
  • Test both passing and failing paths with vm.expectRevert.
  • Add batch helper contracts for multi-operation transactions.
  • Consider property-based testing (Echidna) for state invariants.
  • Run tests with pcl test; it behaves like forge test (same flags, fuzzing, verbosity), but may lag Forge versions.
  • Tests are Solidity functions starting with test; convention is test/*.t.sol.
  • Use FOUNDRY_PROFILE=assertions (or unit/fuzz/backtest profiles) for predictable config.
  • If proxy/delegatecall makes call inputs unreliable, add a log-based assertion variant and test both.

Core Test Patterns

  • Positive path: expected to pass and keep state consistent.
  • Negative path: expected to revert with the assertion message.
  • Edge cases: zero supply, empty vaults, proxy upgrades, nested batches.

Gas Limit Checks

  • Assertions are capped at 300k gas.
  • The happy path is often the most expensive. Test with max sizes.
  • Use pcl test -vvv to inspect per-call gas usage.

Rationalizations to Reject

  • "One passing test is enough." Assertions must also fail on violations.
  • "Gas limits are a production problem." Exceeding 300k drops valid txs.
  • "Fuzzing is optional." It finds edge cases that manual tests miss.

References