Description

After the HIP-3 refactor that replaced webData3 with individual clearinghouseState/openOrders subscriptions, HIP-3 market positions were not showing up on initial load. Additionally, when they did appear (e.g., after switching accounts), there was a ~1 second delay between crypto perps and HIP-3 positions appearing.

Root Cause

A race condition between subscription creation and DEX discovery:

1. HyperLiquidSubscriptionService initializes with empty enabledDexs
   subscribeToPositions() creates subscriptions using empty enabledDexs (main DEX only)
2. DEX discovery runs asynchronously via buildAssetMapping()
3. updateFeatureFlags() is called with discovered DEXs, but subscriptions already exist for main DEX only
4. HIP-3 positions never appear because no subscriptions were created for HIP-3 DEXs

Why switching accounts worked: Account switching triggers reconnectWithNewContext() which performs a full reinitialization. During reconnection, buildAssetMapping() (DEX discovery) completes before createUserDataSubscription() is called, so enabledDexs is already populated and HIP-3 subscriptions are correctly created.

Solution

1. Promise-based DEX discovery wait
   Added dexDiscoveryPromise and dexDiscoveryResolver fields
   createUserDataSubscription() waits for DEX discovery when HIP-3 is enabled but enabledDexs is empty
   updateFeatureFlags() resolves the promise when DEXs are discovered
   5-second timeout prevents indefinite waiting
2. Synchronized position subscription notifications
   Added expectedDexs and initializedDexs tracking sets
   aggregateAndNotifySubscribers() waits for ALL expected DEXs to send initial data before notifying
   Ensures crypto and HIP-3 positions appear simultaneously
3. Consistent position ordering
   Modified aggregation to always show main DEX (crypto perps) first, then HIP-3 positions

Error handling:

1. Failed DEX subscriptions are removed from expectedDexs so they don't block notifications for other DEXs
2. Both ensureClearinghouseStateSubscription and ensureOpenOrdersSubscription mark DEXs as initialize

Changes to HyperLiquidSubscriptionService.ts:

• Added DEX discovery synchronization promise mechanism
• Added expectedDexs/initializedDexs tracking for synchronized notifications
• Added wait logic in createUserDataSubscription() for HIP-3 DEX discovery
• Modified aggregateAndNotifySubscribers() to wait for all DEXs before notifying
• Modified aggregation ordering to put main DEX first
• Added initializedDexs.add() to both subscription callbacks
• Added expectedDexs.delete() in catch blocks for failed subscriptions
• Added cleanup for tracking state in cleanupSharedWebData3Subscription()
• Updated tests to call updateFeatureFlags() to simulate DEX discovery before subscribing in HyperLiquidSubscriptionService.test.ts

Changelog

CHANGELOG entry: Fixes bug where hip3 positions were not loaded on initial PerpsContext load

Related issues

Fixes:

Manual testing steps

Verified crypto and HIP-3 positions appear simultaneously on initial load
Verified position ordering (crypto first, HIP-3 second)
Verified account switching still works correctly
Verified that TP/SL still works as intended

Screenshots/Recordings

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