From df55d48b25698c17743dba3d2ccb9d2b61156603 Mon Sep 17 00:00:00 2001
From: Hotmopo <owolabioluwakemi41@gmail.com>
Date: Thu, 1 Oct 2026 15:43:43 +0000
Subject: [PATCH] fix(#500): avoid double-conversion in unlockAssets wrapper

The unlockAssets wrapper was validating the amount by calling amountToStroops()
and discarding the result, then the service would call amountToStroops() again
for the actual conversion. Now the wrapper captures the converted stroops value
and passes it to the service via a new optional parameter, avoiding the
redundant conversion while maintaining fail-fast validation before wallet
interaction.

Closes #500
---
 src/lib/soroban.ts | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/src/lib/soroban.ts b/src/lib/soroban.ts
index bab3729..8d9ec0f 100644
--- a/src/lib/soroban.ts
+++ b/src/lib/soroban.ts
@@ -1355,6 +1355,8 @@ export class SorobanService {
    * Unlock assets from a pool
    * @param amount - display units as a string, converted to stroops via
    *   amountToStroops — the same contract lockAssets uses (issue #445)
+   * @param amountStroops - optional pre-converted stroops value to avoid
+   *   double-conversion when caller has already validated (issue #500)
    */
   async unlockAssets(
     poolId: string,
@@ -1363,6 +1365,7 @@ export class SorobanService {
     walletApi: FreighterWalletApi,
     callbacks?: UnlockAssetsCallbacks,
     isStillConnected?: () => boolean,
+    amountStroops?: bigint,
   ): Promise<TransactionResult> {
     const poolContract = this.resolvePoolContract(poolId);
 
@@ -1385,10 +1388,12 @@ export class SorobanService {
 
       callbacks?.onStep?.('simulating');
 
+      const stroops = amountStroops ?? amountToStroops(amount);
+
       const call = poolContract.call(
         "unlock_assets",
         Address.fromString(userAddress).toScVal(),
-        nativeToScVal(amountToStroops(amount), { type: "i128" }),
+        nativeToScVal(stroops, { type: "i128" }),
       );
 
       const account = await this.rpcServer.getAccount(userAddress);
@@ -2180,14 +2185,13 @@ export const unlockAssets = async ({
   isStillConnected?: () => boolean;
 } & UnlockAssetsCallbacks) => {
   // Validate the display-unit amount up front so malformed input is rejected
-  // before any wallet/RPC interaction. Both wrappers now pass display units
-  // straight through; the service converts with the same amountToStroops
-  // helper lockAssets uses (issue #445).
-  amountToStroops(amount);
+  // before any wallet/RPC interaction. Capture the converted stroops value
+  // to avoid double-conversion in the service (issue #500).
+  const stroops = amountToStroops(amount);
   return sorobanService.unlockAssets(poolContractId, publicKey, amount, walletApi, {
     onHash,
     onStep,
-  }, isStillConnected);
+  }, isStillConnected, stroops);
 };
 
 export const stellarExpertTxUrl = (hash: string, network: string) =>