Update metadata (Babe updates) (#1410)

* Update metadata (Babe updates)

* Bump with latest master

* Use genesisSlot as opposed to epochStartSlot (wrongly)

* Calculate session from genesis start

* Re-create after master merge

* Kusama CC1 chain type overrides

packages/api-derive/src/session/info.ts

@@ -15,7 +15,7 @@ import { drr } from '../util/drr';
 import { bestNumber } from '../chain';
 
 type Result0to94 = [BlockNumber, [SessionIndex, Option<BlockNumber>, BN, BN, SessionIndex]];
-type Result = [[u64, SessionIndex], [u64, u64, u64], [SessionIndex, EraIndex]];
+type Result = [[boolean, boolean, u64, SessionIndex], [u64, u64, u64], [SessionIndex, EraIndex]];
 
 const ZERO = new BN(0);
 const ONE = new BN(1);
@@ -49,21 +49,24 @@ function createDerived0to94 ([bestNumber, [currentIndex, _lastLengthChange, sess
   } as unknown as DerivedSessionInfo;
 }
 
-function createDerived ([[epochDuration, sessionsPerEra], [currentSlot, epochIndex, epochStartSlot], [currentIndex, currentEra]]: Result): DerivedSessionInfo {
+function createDerived ([[hasBabe, isGenesisSlot, epochDuration, sessionsPerEra], [currentSlot, epochIndex, epochOrGenesisStartSlot], [currentIndex, currentEra]]: Result): DerivedSessionInfo {
+  const epochStartSlot = isGenesisSlot
+    ? epochIndex
+      .mul(epochDuration)
+      .add(epochOrGenesisStartSlot)
+    : epochOrGenesisStartSlot;
   const sessionProgress = currentSlot.sub(epochStartSlot);
   const eraProgress = epochIndex
     .mod(sessionsPerEra)
     .mul(epochDuration)
     .add(sessionProgress);
 
-  // FIXME This alwasy assumes Babe, as per the substrate defaults - at least for
-  // aura the `isEpoch` should be false
   return {
     currentEra,
     currentIndex,
     eraLength: sessionsPerEra.mul(epochDuration),
     eraProgress,
-    isEpoch: true,
+    isEpoch: hasBabe,
     lastEraLengthChange: ZERO,
     lastLengthChange: epochStartSlot,
     sessionLength: epochDuration,
@@ -104,6 +107,8 @@ export function info (api: ApiInterfaceRx): () => Observable<DerivedSessionInfo>
           // substrate spec_version >= 94 : get from parameter_types exposed as api.consts
           // https://github.com/paritytech/substrate/pull/2802/files#diff-5e5e1c3aec9ddfde0a9054d062ab3db9R156
           of([
+            hasBabe,
+            !!api.query.babe.genesisSlot,
             hasBabe
               ? api.consts.babe.epochDuration
               : ONE,
@@ -113,7 +118,9 @@ export function info (api: ApiInterfaceRx): () => Observable<DerivedSessionInfo>
             ? api.queryMulti([
               api.query.babe.currentSlot,
               api.query.babe.epochIndex,
-              api.query.babe.epochStartSlot
+              api.query.babe.genesisSlot
+                ? api.query.babe.genesisSlot
+                : api.query.babe.epochStartSlot
             ])
             : of([ONE, ONE, ONE]),
           api.queryMulti([