Reduce UI lag: YAOB throttle, debounce, dedup, and balance cache

[paullinator]

CHANGELOG

Does this branch warrant an entry to the CHANGELOG?

• Yes
• No

Dependencies

none

Description

Reduces RN JS thread starvation during wallet scene transitions by cutting redundant YAOB bridge crossings and Redux dispatches. Six targeted fixes:

• Seed balanceMap from wallet cache: Initialize balanceMap from cached balances via a new ACCOUNT_CACHED_BALANCES_LOADED action, eliminating a wave of redundant onTokenBalanceChanged callbacks on startup. Adds an early-return guard to drop callbacks when the value matches the current Redux state.
• Increase YAOB throttle 50ms → 200ms: Reduces peak bridge message frequency by 4x across all wallets.
• Debounce update(walletApi) to 300ms: Collapses rapid-fire Redux state mutations into a single bridge crossing per wallet. Adds hasYaobVisibleChange to skip no-op updates for internal-only field changes.
• Slow updateQueue to 1 item per 1000ms: Prevents the queue from flooding the JS thread during the post-login sync burst.
• Gate CURRENCY_ENGINE_CHANGED_TXS dispatch: Only dispatches when compare() finds actual changed/created transactions.
• Dedup balanceMap reducer: Returns the existing Map reference when the balance value is unchanged, preventing spurious watcher triggers.

---

Note

Medium Risk
Touches login sequencing, wallet/config objects, and disk-backed caching, which can affect startup behavior and wallet visibility if cache data is stale/invalid or delegation/polling misbehaves. Changes also alter update/dispatch timing, so regressions may show up as delayed UI refreshes or missed updates.

Overview
Adds a cache-first login path that loads a per-account walletCache.json to instantly expose lightweight EdgeCurrencyWallet/EdgeCurrencyConfig stubs (with delegation/polling to real engines), and merges these cached wallets into EdgeAccount.currencyWallets until engines finish loading.

Introduces wallet-cache persistence: a throttled cacheSaver pixie writes tokens/customTokens, wallet metadata, balances, enabled tokens, and otherMethods names; cached balances are dispatched via new ACCOUNT_CACHED_BALANCES_LOADED so wallet reducers seed balanceMap without a startup callback storm. Adds extensive end-to-end tests plus deterministic fake-plugin gating for engine load.

Reduces UI/bridge churn by increasing YAOB_THROTTLE_MS (50→200), debouncing wallet update(walletApi) with a YAOB-visible-field diff, deduping no-op balance/token/tx Redux dispatches, and slowing updateQueue cadence.

^{Written by Cursor Bugbot for commit 19b037e. This will update automatically on new commits. Configure here.}

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

^{Bugbot Autofix is ON. A Cloud Agent has been kicked off to fix the reported issue.}

[cursor]

Debounce timer uses stale closure over walletState

Medium Severity

The setTimeout callback on line 476 captures walletState from the enclosing async function's local scope. This value is frozen to whatever state existed when the timer was first created. During the 300ms debounce window, subsequent updates set updatePending = true but the timer still holds the stale walletState. When the timer fires, hasYaobVisibleChange compares the stale snapshot (not the latest state) against lastUpdatedState, and lastUpdatedState is then set to the stale value. This causes lastUpdatedState to diverge from what yaob actually received, which can lead to skipped update(walletApi) calls in subsequent debounce windows. Using the outer-scope lastState variable (which always holds the most recent state) instead of the closure-captured walletState would fix this.

 

[cursor]

Bugbot Autofix prepared fixes for 1 of the 1 bugs found in the latest run.

• ✅ Fixed: Debounce timer uses stale closure over walletState
  • Changed the setTimeout callback to use the outer-scope lastState variable instead of the closure-captured walletState, ensuring the timer uses the most recent state when it fires.

Or push these changes by commenting:

@cursor push e705a0120b

Preview (e705a0120b)

diff --git a/src/core/currency/wallet/currency-wallet-pixie.ts b/src/core/currency/wallet/currency-wallet-pixie.ts
--- a/src/core/currency/wallet/currency-wallet-pixie.ts
+++ b/src/core/currency/wallet/currency-wallet-pixie.ts
@@ -473,8 +473,11 @@
             updateTimer = undefined
             if (updatePending) {
               updatePending = false
-              if (hasYaobVisibleChange(walletState, lastUpdatedState)) {
-                lastUpdatedState = walletState
+              if (
+                lastState != null &&
+                hasYaobVisibleChange(lastState, lastUpdatedState)
+              ) {
+                lastUpdatedState = lastState
                 update(walletApi)
               }
             }