Cardano Updates

Signed-off-by: Jonathan Lim <[email protected]>

Signed-off-by: KtorZ <[email protected]>

Signed-off-by: Eric Torreborre <[email protected]>

Signed-off-by: Chris Gianelloni <[email protected]>

  This is more convenient and easier to document than some opaque configuration file. One can still use a config file which would export ENV vars.

Signed-off-by: KtorZ <[email protected]>

  It is not okay to change production behavior to accomodate tests; this is dangerous and will send even send a wrong test signal. We should test the code that ends up in production.

  Note that I've kept some of the ideas behind the hack to make the stake distribution resolution a bit more flexible while remaining correct. This is mostly just deferring the error to later; but no longer tries to return a placeholder stake distribution when not found.

Signed-off-by: KtorZ <[email protected]>

Port of lambdasistemi 36ea009c onto upstream/main's rewritten state.rs.

Generated private testnets (db-synthesizer / amaru-bootstrap) can serve
block headers from the next leader schedule before the stable ledger
has materialized that epoch's snapshot. Add an opt-in forecast on
StakeDistributionObserver::get_pool that falls back to the latest
cached distribution when the requested epoch is strictly newer; only
enabled for NetworkName::Testnet(_).

Public networks (mainnet/preprod/preview) keep the existing strict
lookup behaviour.

Signed-off-by: paolino <[email protected]>

Signed-off-by: KtorZ <[email protected]>

  This matches the Haskell's behaviour; and is a lot more sound than returning 1 (which simply bypass the leader schedule stake check).

Signed-off-by: KtorZ <[email protected]>

Signed-off-by: paolino <[email protected]>

The node-snapshot (tvar) import path derived the current era's epoch size
from the network default (86400), ignoring custom-testnet genesis. Load the
history.<slot>.<hash>.json sidecar (as the .cbor path already does via
make_era_history) and use it to interpret the snapshot, but only for
Testnet(_); public networks keep the snapshot-derived history unchanged.

Signed-off-by: paolino <[email protected]>

Two sites in amaru-ledger/src/state.rs were doing unchecked Epoch
subtraction on a u64-backed Epoch, producing u64::MAX-1 (or panicking,
depending on overflow checks) when the latest snapshot or the
slot-derived current epoch was below the rewards/leader-schedule
horizon (epoch < 2):

- StakeDistributionObserver::get_pool: `current_epoch - 2` becomes
  saturating_sub(2). Headers validated very early in the chain (or
  with a custom era history that maps slots to low epoch numbers)
  no longer surface a misleading
  "no stake distribution available for pool access 18446744073709551614"
  — the error now correctly says "pool access 0" and points at a
  real missing snapshot.

- initial_stake_distributions: `latest_epoch - Epoch::from(2)` and
  `- Epoch::from(1)` become saturating_sub(2) / saturating_sub(1).
  Bundles produced by amaru-bootstrap from cold-start short-epoch
  testnets (e.g. lambdasistemi/amaru-bootstrap#34's antithesis
  reproducer) where the most_recent_snapshot is epoch 0 or 1 no
  longer hit a u64 underflow on Ledger::new; for_epoch(0) is
  exercised normally and surfaces a sensible StoreError if the
  snapshot is genuinely absent.

This is a defensive correctness improvement only — it does not change
behaviour for any chain past epoch 2. Surfaced by the new live
amaru-run consumer test in lambdasistemi/amaru-bootstrap#35.

Signed-off-by: Paolo Veronelli <[email protected]>
Signed-off-by: paolino <[email protected]>

Signed-off-by: paolino <[email protected]>

Signed-off-by: paolino <[email protected]>

GetAccountState is a Conway-era query; add the same era guard the other
Conway governance client methods (GetConstitution, GetGovState, GetDRepState)
use, so calling it on a pre-Conway chain returns a clear error instead of
sending an unsupported query.

Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>
Signed-off-by: Chris Guiney <[email protected]>

Signed-off-by: Chris Gianelloni <[email protected]>

by extracting the shared logic in helpers

Signed-off-by: Chris Gianelloni <[email protected]>