TypeScript SDK's filterMarkets misreads resolutionDate filter — markets with no resolutionDate are included instead of excluded #2369

Gap

Core's filterMarkets explicitly excludes a market from resolutionDate filtering when the market has no resolutionDate set. The TypeScript SDK's reimplementation does the opposite: it silently includes such markets, because its guard condition requires market.resolutionDate to be truthy before applying (or skipping) the filter.

Core

core/src/BaseExchange.ts:1435-1444:

if (criteria.resolutionDate) {
    const resDate = market.resolutionDate;
    if (!resDate) return false;   // <-- exclude when missing
    if (criteria.resolutionDate.before && resDate >= criteria.resolutionDate.before) return false;
    if (criteria.resolutionDate.after && resDate <= criteria.resolutionDate.after) return false;
}

TypeScript SDK

sdks/typescript/pmxt/client.ts:3089 — the equivalent block is gated as if (criteria.resolutionDate && market.resolutionDate), so when market.resolutionDate is falsy the whole block is skipped and the market passes the filter (included) instead of being excluded.

Python SDK

Not checked in this pass — flag for a follow-up spot check since the Python filter_markets implementation was otherwise found to match core.

Evidence

Read core/src/BaseExchange.ts:1435-1444 and sdks/typescript/pmxt/client.ts:3089 side by side; the divergent null-handling was confirmed directly in both files.

Impact

exchange.filterMarkets(markets, { resolutionDate: { before: X } }) returns a different result set in the TypeScript SDK than the equivalent call against core for any market missing a resolutionDate — the SDK silently includes markets that core would exclude.

Found by automated Core-to-SDK surface coverage audit