Runtime Source Fixtures

Test runners: Examples in this section use Vitest. scenario(...) returns an async function compatible with other test(...)-style runners (for example Jest or Node node:test).

Statecraft scenarios require a runtime and viem clients. These fixtures provide the base runtime context and are generally mutually exclusive in normal scenarios.

Use exactly one of withChain, withFork, or withExternalRuntime as your base runtime step. Everything else (wallet funding, ERC-20 seeding, contracts, and isolation) assumes this base step exists.

Fixtures

• withChain()
• withFork({ rpcUrl, blockNumber })
• withExternalRuntime({ runtime, runtimeMode?, clients? })

Additional wiring

• withBundler({ entryPoint, mode? })
• withBundler requires fork runtime mode (withFork(...), or external runtime declared with runtimeMode: "fork").