Struct CostEstimate

pub struct CostEstimate { /* private fields */ }

Available on crate feature testutils only.

Implementations

impl CostEstimate

pub fn resources(&self) -> InvocationResources

Returns the resources metered during the last top level contract invocation.
Take the return value with a grain of salt. The returned resources mostly correspond only to the operations that have happened during the host invocation, i.e. this won’t try to simulate the work that happens in production scenarios (e.g. certain XDR rountrips). This also doesn’t try to model resources related to the transaction size.

The returned value is as useful as the preceding setup, e.g. if a test contract is used instead of a Wasm contract, all the costs related to VM instantiation and execution, as well as Wasm reads/rent bumps will be missed.

pub fn fee(&self) -> FeeEstimate

Estimates the fee for the last invocation’s resources, i.e. the resources returned by resources().

The fees are computed using the snapshot of the Stellar Pubnet fees made on 2024-12-11.

Take the return value with a grain of salt as both the resource estimate and the fee rates may be imprecise.

The returned value is as useful as the preceding setup, e.g. if a test contract is used instead of a Wasm contract, all the costs related to VM instantiation and execution, as well as Wasm reads/rent bumps will be missed.

pub fn budget(&self) -> Budget

Returns the budget object that provides the detailed CPU and memory metering information recorded thus far.

The budget metering resets before every top-level contract level invocation.

budget() may also be used to adjust the CPU and memory limits via the reset_ methods.

Note, that unlike resources()/fee() this will always return some value. If there was no contract call, then the resulting value will correspond to metering any environment setup that has been made thus far.