TODO

lib.rs:

The Stylus testing suite.

The stylus-test crate makes it easy to unit test all the storage types and contracts that use the Stylus SDK. Included is an implementation of the stylus_core::host::Host trait that all Stylus contracts have access to for interfacing with their host environment.

The mock implementation, named crate::TestVM, can be used to unit test Stylus contracts in native Rust without the need for a real EVM or Arbitrum chain environment. crate::TestVM allows for mocking of all host functions, including storage, gas, and external calls to assert contract behavior.

To be able to unit test Stylus contracts, contracts must access host methods through the stylus_core::host:HostAccessor trait, which gives all contracts access to a .vm() method. That is, instead of calling stylus_sdk::msg::value() directly, contracts should do self.vm().msg_value(). Global host function invocations are deprecated as of Stylus SDK 0.8.0, and contracts should upgrade to the new host accessor pattern in preparation for 1.0.0.