Merge pull request #7463 from BitGo/WIN-7828-qty-validation-fix

fix(sdk-coin-ada): shouldn't throw insufficient qty for total token s…

Author: Ranjna-G

modules/sdk-coin-ada/src/lib/transactionBuilder.ts

@@ -259,12 +259,12 @@ export abstract class TransactionBuilder extends BaseTransactionBuilder {
 
           const currentQty = this._mutableSenderAssetList[fingerprint].quantity;
           const remainingQty = BigInt(currentQty) - BigInt(quantity);
-          this._mutableSenderAssetList[fingerprint].quantity = (remainingQty > 0n ? remainingQty : 0n).toString();
-
-          if (CardanoWasm.BigNum.from_str(this._mutableSenderAssetList[fingerprint].quantity).is_zero()) {
+          if (remainingQty < 0n) {
             throw new BuildTransactionError('Insufficient qty: not enough token qty to cover receiver output');
           }
 
+          this._mutableSenderAssetList[fingerprint].quantity = remainingQty.toString();
+
           const minAmountNeededForAssetOutput = this.addTokensToOutput(change, outputs, receiverAddress, {
             policy_id: policyId,
             asset_name: assetName,

modules/sdk-coin-ada/test/unit/tokenWithdrawal.ts

@@ -291,4 +291,39 @@ describe('ADA Token Operations', async () => {
 
     await txBuilder.build().should.rejectedWith('Insufficient qty: not enough token qty to cover receiver output');
   });
+
+  it(`should build a transaction with ${assetName} when the token qty is exactly the qty in withdrawal`, async () => {
+    const quantity = '1';
+    const totalInput = 20000000;
+    const totalAssetList = {
+      [fingerprint]: {
+        quantity: '1',
+        policy_id: policyId,
+        asset_name: asciiEncodedName,
+      },
+    };
+
+    const txBuilder = factory.getTransferBuilder();
+    txBuilder.input({
+      transaction_id: '3677e75c7ba699bfdc6cd57d42f246f86f63aefd76025006ac78313fad2bba21',
+      transaction_index: 1,
+    });
+
+    txBuilder.output({
+      address: receiverAddress,
+      amount: '0', // Set ADA amount to 0 for token transfer (min ADA is handled in sdk build)
+      multiAssets: {
+        asset_name: asciiEncodedName,
+        policy_id: policyId,
+        quantity,
+        fingerprint,
+      },
+    });
+
+    txBuilder.changeAddress(senderAddress, totalInput.toString(), totalAssetList);
+    txBuilder.ttl(800000000);
+    txBuilder.isTokenTransaction();
+
+    await txBuilder.build().should.not.be.rejected();
+  });
 });