foundry

Integration and fuzz tests in Foundry validate contract behavior under normal and randomized inputs. Foundry's integration tests execute full contract workflows, while fuzz tests automatically generate varied inputs to uncover edge cases. Both run with forge test and support assertions across state changes and function calls.

Invariant tests verify properties that must always hold true in your contract, regardless of input sequences. Foundry's invariant testing framework generates random function call sequences and checks that your defined invariants remain valid throughout execution, catching violations that break contract assumptions.

Fork tests simulate mainnet or testnet states locally, letting you test against real contract states without testnet dependency. Foundry supports fork testing via RPC endpoints. Deployment scripts in the scripts/ directory automate contract deployment across environments using forge script for consistent, repeatable deployment workflows.

Yes, Foundry tooling must be installed on your system to write and execute tests. This Skill requires access to Foundry's command-line tools and bundled references that document patterns, cheat codes, and test structure for building robust test suites in the tests/ and scripts/ directories.

Foundry follows standard conventions: place test files in the tests/ directory and deployment or utility scripts in the scripts/ directory. This Skill provides patterns and references to guide file organization, naming conventions, and test authoring workflows that align with Foundry's expected project layout.

Structured, repeatable Foundry tests catch regressions by validating contract behavior across integration, fuzz, fork, and invariant test types. This Skill automates test authoring and provides guided workflows to scaffold reliable test suites that guard against state and logic regressions throughout contract development.