Function mergeCellsOrValues

src/mergeable-store/index.ts:271–324

(
    things: typeof isContent extends 1
      ? Stamp<IdObj<Stamp<Thing, true>>, true>
      : Stamp<IdObj<Stamp<Thing>>>,
    thingsStampMap: StampMap<Stamp<Thing, true>>,
    thingsChanges: {[thingId: Id]: Thing},
    isContent: 0 | 1,
  )

  };

  const mergeCellsOrValues = <Thing extends CellOrUndefined | ValueOrUndefined>(
    things: typeof isContent extends 1
      ? Stamp<IdObj<Stamp<Thing, true>>, true>
      : Stamp<IdObj<Stamp<Thing>>>,
    thingsStampMap: StampMap<Stamp<Thing, true>>,
    thingsChanges: {[thingId: Id]: Thing},
    isContent: 0 | 1,
  ): [thingsHlc: Hlc, oldThingsHash: number, newThingsHash: number] => {
    const [
      thingsObj,
      incomingThingsHlc = EMPTY_STRING,
      incomingThingsHash = 0,
    ] = things;
    const [thingStampMaps, oldThingsHlc, oldThingsHash] = thingsStampMap;

    let thingsHlc = incomingThingsHlc;
    let thingsHash = isContent ? incomingThingsHash : oldThingsHash;

    objForEach(
      thingsObj,
      ([thing, thingHlc = EMPTY_STRING, incomingThingHash = 0], thingId) => {
        const thingStampMap = mapEnsure<Id, Stamp<Thing, true>>(
          thingStampMaps,
          thingId,
          () => [undefined as any, EMPTY_STRING, 0],
        );
        const [, oldThingHlc, oldThingHash] = thingStampMap;

        if (!oldThingHlc || thingHlc > oldThingHlc) {
          stampUpdate(
            thingStampMap,
            thingHlc,
            isContent ? incomingThingHash : getValueHash(thing, thingHlc),
          );
          thingStampMap[0] = thing;
          thingsChanges[thingId] = thing;
          thingsHash ^= isContent
            ? 0
            : addOrRemoveHash(
                getValueInValuesHash(thingId, oldThingHash),
                getValueInValuesHash(thingId, thingStampMap[2]),
              );
          thingsHlc = getLatestHlc(thingsHlc, thingHlc);
        }
      },
    );

    thingsHash ^= isContent
      ? 0
      : replaceHlcHash(oldThingsHlc, incomingThingsHlc);
    stampUpdate(thingsStampMap, incomingThingsHlc, thingsHash);

    return [thingsHlc, oldThingsHash, thingsStampMap[2]];
  };

  const preStartTransaction = noop;