Trait CollateralSlasher 

pub trait CollateralSlasher {
    // Required method
    fn credit(&mut self, validator_index: u32, amount_mojos: u64);

    // Provided method
    fn slash(
        &mut self,
        _validator_index: u32,
        _amount_mojos: u64,
        _epoch: u64,
    ) -> Result<(u64, u64), CollateralError> { ... }
}

Collateral-slash reversal surface.

Traces to SPEC §15.3, catalogue row DSL-065.

Consumer

• Appeal adjudication (DSL-065) calls credit(validator_index, amount_mojos) per reverted validator when a CollateralSlasher is supplied. Semantically a revert of the consensus-layer collateral debit that ran alongside the ValidatorEntry::slash_absolute stake debit at admission.

Optional wiring

Light-client deployments may not track collateral at all. The adjudicator accepts Option<&mut dyn CollateralSlasher> and no-ops when None — collateral revert is a full-node concern.

Idempotence

The trait does not specify idempotence. Callers MUST call credit exactly once per reverted validator — the adjudicator does so by construction (one pass over base_slash_per_validator).

Required Methods

fn credit(&mut self, validator_index: u32, amount_mojos: u64)

Credit amount_mojos of collateral back to validator_index. Consensus-layer impl restores whatever collateral-position bookkeeping it chose to debit at admission.

Provided Methods

fn slash( &mut self, _validator_index: u32, _amount_mojos: u64, _epoch: u64, ) -> Result<(u64, u64), CollateralError>

Debit amount_mojos of collateral from validator_index at epoch. Implements the slash leg of DSL-139; companion to credit.

Default impl returns Err(CollateralError::NoCollateral): current production wiring only uses credit (via DSL-129 reorg rewind + DSL-065 sustained-appeal revert); collateral debits land later under a consensus-layer slasher. Providing a default keeps every existing impl CollateralSlasher (test spies + future production impls) working without a breaking signature change.

Returns

• Ok((slashed, remaining)) — actual debit and post- debit collateral balance.
• Err(CollateralError::NoCollateral) — validator has no collateral position. Soft failure; DSL-022 submit_evidence ignores this and still slashes stake.

Implementors