fix(sdk-coin-xrp): include SendMax, Paths and DeliverMin in Payment explanation

modules/sdk-coin-xrp/src/lib/iface.ts

@@ -139,6 +139,15 @@ export interface PaymentTransactionExplanation extends BaseTransactionExplanatio
    * this flag is still set so consumers can distinguish partial from full delivery.
    */
   partialPayment?: boolean;
+  sendMax?: Amount | MPTAmount;
+  hasPaths?: boolean;
+  deliverMin?: Amount | MPTAmount;
+}
+
+export interface PaymentSpendLimits {
+  sendMax?: Amount | MPTAmount;
+  hasPaths?: boolean;
+  deliverMin?: Amount | MPTAmount;
 }
 
 export interface AccountSetTransactionExplanation extends BaseTransactionExplanation {

modules/sdk-coin-xrp/src/lib/transaction.ts

@@ -267,6 +267,7 @@ export class Transaction extends BaseTransaction {
     // *requested* amount, not what was actually delivered — surface that via the flag so
     // consumers don't treat outputAmount as the settled value.
     const partialPayment = utils.isPartialPayment(tx.Flags as number);
+    const spendLimits = utils.getPaymentSpendLimits(tx);
 
     return {
       displayOrder: [
@@ -277,6 +278,7 @@ export class Transaction extends BaseTransaction {
         'changeOutputs',
         'fee',
         ...(partialPayment ? ['partialPayment'] : []),
+        ...Object.keys(spendLimits),
       ],
       id: this._id as string,
       changeOutputs: [],
@@ -293,6 +295,7 @@ export class Transaction extends BaseTransaction {
         feeRate: undefined,
       },
       ...(partialPayment ? { partialPayment: true } : {}),
+      ...spendLimits,
     };
   }
 

modules/sdk-coin-xrp/src/lib/utils.ts

@@ -12,7 +12,7 @@ import * as url from 'url';
 import * as xrpl from 'xrpl';
 import { Amount, IssuedCurrencyAmount, isMPTAmount, MPTAmount } from 'xrpl';
 import { TF_PARTIAL_PAYMENT, VALID_ACCOUNT_SET_FLAGS } from './constants';
-import { Address, SignerDetails } from './iface';
+import { Address, PaymentSpendLimits, SignerDetails } from './iface';
 import { KeyPair as XrpKeyPair } from './keyPair';
 import assert from 'assert';
 
@@ -242,6 +242,14 @@ class Utils implements BaseUtils {
     return (Number(flags) & TF_PARTIAL_PAYMENT) !== 0;
   }
 
+  public getPaymentSpendLimits(tx: xrpl.Payment): PaymentSpendLimits {
+    return {
+      ...(tx.SendMax !== undefined ? { sendMax: tx.SendMax } : {}),
+      ...(tx.Paths !== undefined ? { hasPaths: true } : {}),
+      ...(tx.DeliverMin !== undefined ? { deliverMin: tx.DeliverMin } : {}),
+    };
+  }
+
   /**
    * Extracts the numeric/string delivered amount value from XRP transaction metadata.
    * `meta.delivered_amount` is an `Amount | 'unavailable'`:

modules/sdk-coin-xrp/src/xrp.ts

@@ -353,6 +353,7 @@ export class Xrp extends BaseCoin {
       const partialPayment = utils.isPartialPayment(transaction.Flags as number);
       const deliveredValue = partialPayment ? utils.getDeliveredAmountValue(params.meta) : undefined;
       const outputAmount = deliveredValue !== undefined ? deliveredValue : transaction.Amount;
+      const spendLimits = utils.getPaymentSpendLimits(transaction);
       return {
         displayOrder: [
           'id',
@@ -362,6 +363,7 @@ export class Xrp extends BaseCoin {
           'changeOutputs',
           'fee',
           ...(partialPayment ? ['partialPayment'] : []),
+          ...Object.keys(spendLimits),
         ],
         id: id,
         changeOutputs: [],
@@ -379,6 +381,7 @@ export class Xrp extends BaseCoin {
           size: txHex.length / 2,
         },
         ...(partialPayment ? { partialPayment: true } : {}),
+        ...spendLimits,
       };
     }
 

modules/sdk-coin-xrp/test/unit/xrp.ts

@@ -12,7 +12,8 @@ import * as nock from 'nock';
 import * as rippleBinaryCodec from 'ripple-binary-codec';
 import sinon from 'sinon';
 import * as xrpl from 'xrpl';
-import { XrpToken } from '../../src';
+import { Transaction, XrpToken } from '../../src';
+import { coins } from '@bitgo/statics';
 import * as testData from '../resources/xrp';
 import { SIGNER_BACKUP, SIGNER_BITGO, SIGNER_USER } from '../resources/xrp';
 import { getMptBuilderFactory } from './getBuilderFactory';
@@ -484,6 +485,54 @@ describe('XRP:', function () {
     explanation.outputAmount.should.equal('0.005');
   });
 
+  describe('Payment spend limits (SendMax, Paths, DeliverMin)', function () {
+    const crossCurrencyPayment = {
+      TransactionType: 'Payment',
+      Account: 'rBSpCz8PafXTJHppDcNnex7dYnbe3tSuFG',
+      Destination: 'rfjub8A4dpSD5nnszUFTsLprxu1W398jwc',
+      Amount: '1',
+      SendMax: {
+        currency: '524C555344000000000000000000000000000000',
+        issuer: 'rQhWct2fv4Vc4KRjRgMrxa8xPN9Zx9iLKV',
+        value: '100000',
+      },
+      Paths: [[{ currency: 'USD', issuer: 'rQhWct2fv4Vc4KRjRgMrxa8xPN9Zx9iLKV', type: 48 }]],
+      DeliverMin: '1',
+      Flags: 2147483648,
+      Fee: '45',
+      Sequence: 7,
+    };
+
+    it('should surface SendMax, Paths and DeliverMin in the explanation', async function () {
+      const explanation = await basecoin.explainTransaction({ txHex: JSON.stringify(crossCurrencyPayment) });
+      explanation.sendMax.should.deepEqual(crossCurrencyPayment.SendMax);
+      explanation.hasPaths.should.equal(true);
+      explanation.deliverMin.should.equal('1');
+      explanation.displayOrder.should.containEql('sendMax');
+      explanation.displayOrder.should.containEql('hasPaths');
+      explanation.displayOrder.should.containEql('deliverMin');
+    });
+
+    it('should surface the same fields from the lib-level transaction explainer', async function () {
+      // xrpl rejects DeliverMin without tfPartialPayment, so this payload omits it.
+      const paymentWithoutDeliverMin = _.omit(crossCurrencyPayment, 'DeliverMin');
+      const txHex = xrpl.encode(paymentWithoutDeliverMin as xrpl.Payment);
+      const transaction = new Transaction(coins.get('txrp'));
+      transaction.fromRawTransaction(txHex);
+      const explanation = transaction.explainTransaction();
+      explanation.sendMax.should.deepEqual(crossCurrencyPayment.SendMax);
+      explanation.hasPaths.should.equal(true);
+    });
+
+    it('should not add spend-limit fields to a plain payment', async function () {
+      const plainPayment = _.omit(crossCurrencyPayment, ['SendMax', 'Paths', 'DeliverMin']);
+      const explanation = await basecoin.explainTransaction({ txHex: JSON.stringify(plainPayment) });
+      explanation.should.not.have.property('sendMax');
+      explanation.should.not.have.property('hasPaths');
+      explanation.should.not.have.property('deliverMin');
+    });
+  });
+
   describe('Fee Management', () => {
     const nockBasecoin: any = bitgo.coin('txrp');