code review

Author: atn4z7

packages/core-mobile/app/new/features/swapV2/consts.ts

@@ -1,3 +1,4 @@
+import Config from 'react-native-config'
 import { Environment } from '@avalabs/unified-asset-transfer'
 import { BuildTxParams } from "features/swap/services/ParaswapService"
 
@@ -100,7 +101,7 @@ export const MAX_SLIPPAGE_PERCENT = 50
  */
 // TODO add to env variables once stable
 export const MARKR_API_URL =
-  process.env.MARKR_API_URL ?? 'https://proxy-api.avax.network/proxy/markr-staging'
+  Config.MARKR_API_URL ?? 'https://proxy-api.avax.network/proxy/markr-staging'
 
 /**
  * Determines the Fusion SDK environment based on app settings

packages/core-mobile/app/new/features/swapV2/hooks/useSupportedChains.ts

@@ -4,6 +4,7 @@ import type { Network } from '@avalabs/core-chains-sdk'
 import { ReactQueryKeys } from 'consts/reactQueryKeys'
 import { useNetworks } from 'hooks/networks/useNetworks'
 import Logger from 'utils/Logger'
+import { exponentialBackoff } from 'utils/reactQuery'
 import { isAvalancheChainId } from 'services/network/utils/isAvalancheNetwork'
 import FusionService from '../services/FusionService'
 
@@ -41,7 +42,8 @@ export function useSupportedChains(): {
       return FusionService.getSupportedChains()
     },
     staleTime: STALE_TIME,
-    enabled: FusionService.isInitialized()
+    retry: 3,
+    retryDelay: exponentialBackoff(5000)
   })
 
   // Convert CAIP-2 IDs to Network objects from enabled networks
@@ -53,8 +55,11 @@ export function useSupportedChains(): {
       .filter((network): network is Network => network !== undefined)
       .sort((a, b) => {
         // Avalanche C-Chain always first
-        if (isAvalancheChainId(a.chainId)) return -1
-        if (isAvalancheChainId(b.chainId)) return 1
+        const aIsAvalanche = isAvalancheChainId(a.chainId)
+        const bIsAvalanche = isAvalancheChainId(b.chainId)
+
+        if (aIsAvalanche && !bIsAvalanche) return -1
+        if (!aIsAvalanche && bIsAvalanche) return 1
         return 0
       })
 

packages/core-mobile/app/store/rpc/utils/assert.ts

@@ -7,11 +7,15 @@ import { rpcErrors } from '@metamask/rpc-errors'
  * @param value - The value to check
  * @param message - Optional error message
  * @throws RPC internal error if value is falsy
+ * @example
+ *   const foo: string | null = getValue()
+ *   assert(foo, 'foo is required')
+ *   // foo is now typed as string (non-nullable)
  */
-export function assert(
-  value: unknown,
+export function assert<T>(
+  value: T,
   message?: string
-): asserts value is NonNullable<unknown> {
+): asserts value is NonNullable<T> {
   if (!value) {
     throw rpcErrors.internal({
       data: { reason: message || 'Assertion failed' }

packages/core-mobile/app/utils/api/clients/profileApiClient.ts

@@ -1,8 +1,14 @@
 import Config from 'react-native-config'
+import Logger from 'utils/Logger'
 import { appCheckFetch } from '../common/appCheckFetch'
 import { CORE_HEADERS } from '../constants'
 import { createClient } from '../generated/profileApi.client/client'
 
+if (!Config.CORE_PROFILE_URL)
+  Logger.warn(
+    'CORE_PROFILE_URL is missing in env file. Profile API will not work properly.'
+  )
+
 /**
  * Profile API client configured with:
  * - nitroFetch (via appCheckFetch) for better performance

packages/core-mobile/app/utils/reactQuery.ts

@@ -0,0 +1,23 @@
+/**
+ * React Query utility functions
+ */
+
+/**
+ * Exponential backoff with a maximum delay cap for React Query retries
+ *
+ * @param maxDelayMs - Maximum delay in milliseconds (default: 5000ms)
+ * @returns Function compatible with React Query's retryDelay option
+ *
+ * @example
+ * useQuery({
+ *   queryKey: ['data'],
+ *   queryFn: fetchData,
+ *   retry: 3,
+ *   retryDelay: exponentialBackoff(5000) // 1s, 2s, 4s
+ * })
+ */
+export const exponentialBackoff = (maxDelayMs = 5000) => {
+  return (attemptIndex: number): number => {
+    return Math.min(1000 * 2 ** attemptIndex, maxDelayMs)
+  }
+}