Struct ReplayHarness 

pub struct ReplayHarness;

Drives an Eventsourced aggregate through a recorded entry stream, restoring RNG state first so derived computation is bit-identical to the original run.

Replay contract

For each recorded PersistentRepr in sequence order:

• ExternalCommand entries are decoded and applied as recorded — they represent inputs the aggregate cannot reproduce on its own.
• DerivedEvent entries (and untagged entries, treated as derived) are decoded, applied, and — when the caller routes the originating command back through command_to_events — compared byte-for-byte against the recording. Any mismatch flips ReplayReport::matched to false.

The harness is intentionally generic and minimal: state is rebuilt purely by apply_event, so two replays from the same seed + snapshot yield identical Eventsourced::State.

Implementations

impl ReplayHarness

pub fn replay<E, F, G>( rng_state: RngState, state: &mut E::State, recorded: &[PersistentRepr], decode: F, re_encode: G, ) -> ReplayReport

where E: Eventsourced, F: FnMut(&[u8]) -> Option<E::Event>, G: FnMut(&E::Event) -> Vec<u8>,

Replay recorded entries into state, restoring rng_state first.

decode turns a payload into an event; re_encode re-serializes a recomputed derived event so it can be compared against the recording. Returns a ReplayReport.