From baf4b8381f32d00e05d4e5bc0598d14ab80c00ac Mon Sep 17 00:00:00 2001
From: Shawn Xie <35279399+shawnxie999@users.noreply.github.com>
Date: Tue, 29 Jul 2025 13:02:33 -0400
Subject: [PATCH] fix `DeliveredAmount` and `delivered_amount` in transaction
 metadata for direct MPT transfer (#5569)

The Payment transaction metadata is missing the `DeliveredAmount` field that displays the actual amount delivered to the destination excluding transfer fees. This amendment fixes this problem.
---
 include/xrpl/protocol/detail/features.macro |  1 +
 src/test/rpc/DeliveredAmount_test.cpp       | 84 +++++++++++++++++++++
 src/xrpld/app/tx/detail/Payment.cpp         |  9 +++
 3 files changed, 94 insertions(+)

diff --git a/include/xrpl/protocol/detail/features.macro b/include/xrpl/protocol/detail/features.macro
index c83dacfa73..e36a466971 100644
--- a/include/xrpl/protocol/detail/features.macro
+++ b/include/xrpl/protocol/detail/features.macro
@@ -32,6 +32,7 @@
 // If you add an amendment here, then do not forget to increment `numFeatures`
 // in include/xrpl/protocol/Feature.h.
 
+XRPL_FIX    (MPTDeliveredAmount,         Supported::no,  VoteBehavior::DefaultNo)
 XRPL_FIX    (AMMClawbackRounding,        Supported::no,  VoteBehavior::DefaultNo)
 XRPL_FEATURE(TokenEscrow,                Supported::yes, VoteBehavior::DefaultNo)
 XRPL_FIX    (EnforceNFTokenTrustlineV2,  Supported::yes, VoteBehavior::DefaultNo)
diff --git a/src/test/rpc/DeliveredAmount_test.cpp b/src/test/rpc/DeliveredAmount_test.cpp
index 17763790e8..d084f92f25 100644
--- a/src/test/rpc/DeliveredAmount_test.cpp
+++ b/src/test/rpc/DeliveredAmount_test.cpp
@@ -21,6 +21,7 @@
 #include <test/jtx/WSClient.h>
 
 #include <xrpl/beast/unit_test.h>
+#include <xrpl/beast/unit_test/suite.h>
 #include <xrpl/protocol/jss.h>
 
 namespace ripple {
@@ -329,12 +330,95 @@ class DeliveredAmount_test : public beast::unit_test::suite
         }
     }
 
+    void
+    testMPTDeliveredAmountRPC(FeatureBitset features)
+    {
+        testcase("MPT DeliveredAmount");
+
+        using namespace jtx;
+        Account const alice("alice");
+        Account const carol("carol");
+        Account const bob("bob");
+        Env env{*this, features};
+
+        MPTTester mptAlice(
+            env, alice, {.holders = {bob, carol}, .close = false});
+
+        mptAlice.create(
+            {.transferFee = 25000,
+             .ownerCount = 1,
+             .holderCount = 0,
+             .flags = tfMPTCanTransfer});
+        auto const MPT = mptAlice["MPT"];
+
+        mptAlice.authorize({.account = bob});
+        mptAlice.authorize({.account = carol});
+
+        // issuer to holder
+        mptAlice.pay(alice, bob, 10000);
+
+        // holder to holder
+        env(pay(bob, carol, mptAlice.mpt(1000)), txflags(tfPartialPayment));
+        env.close();
+
+        // Get the hash for the most recent transaction.
+        std::string txHash{
+            env.tx()->getJson(JsonOptions::none)[jss::hash].asString()};
+        Json::Value meta = env.rpc("tx", txHash)[jss::result][jss::meta];
+
+        if (features[fixMPTDeliveredAmount])
+        {
+            BEAST_EXPECT(
+                meta[sfDeliveredAmount.jsonName] ==
+                STAmount{MPT(800)}.getJson(JsonOptions::none));
+            BEAST_EXPECT(
+                meta[jss::delivered_amount] ==
+                STAmount{MPT(800)}.getJson(JsonOptions::none));
+        }
+        else
+        {
+            BEAST_EXPECT(!meta.isMember(sfDeliveredAmount.jsonName));
+            BEAST_EXPECT(
+                meta[jss::delivered_amount] = Json::Value("unavailable"));
+        }
+
+        env(pay(bob, carol, MPT(1000)),
+            sendmax(MPT(1200)),
+            txflags(tfPartialPayment));
+        env.close();
+
+        txHash = env.tx()->getJson(JsonOptions::none)[jss::hash].asString();
+        meta = env.rpc("tx", txHash)[jss::result][jss::meta];
+
+        if (features[fixMPTDeliveredAmount])
+        {
+            BEAST_EXPECT(
+                meta[sfDeliveredAmount.jsonName] ==
+                STAmount{MPT(960)}.getJson(JsonOptions::none));
+            BEAST_EXPECT(
+                meta[jss::delivered_amount] ==
+                STAmount{MPT(960)}.getJson(JsonOptions::none));
+        }
+        else
+        {
+            BEAST_EXPECT(!meta.isMember(sfDeliveredAmount.jsonName));
+            BEAST_EXPECT(
+                meta[jss::delivered_amount] = Json::Value("unavailable"));
+        }
+    }
+
 public:
     void
     run() override
     {
+        using namespace test::jtx;
+        FeatureBitset const all{testable_amendments()};
+
         testTxDeliveredAmountRPC();
         testAccountDeliveredAmountSubscribe();
+
+        testMPTDeliveredAmountRPC(all - fixMPTDeliveredAmount);
+        testMPTDeliveredAmountRPC(all);
     }
 };
 
diff --git a/src/xrpld/app/tx/detail/Payment.cpp b/src/xrpld/app/tx/detail/Payment.cpp
index 692e03109e..386b170ed1 100644
--- a/src/xrpld/app/tx/detail/Payment.cpp
+++ b/src/xrpld/app/tx/detail/Payment.cpp
@@ -580,7 +580,16 @@ Payment::doApply()
         auto res = accountSend(
             pv, account_, dstAccountID, amountDeliver, ctx_.journal);
         if (res == tesSUCCESS)
+        {
             pv.apply(ctx_.rawView());
+
+            // If the actual amount delivered is different from the original
+            // amount due to partial payment or transfer fee, we need to update
+            // DelieveredAmount using the actual delivered amount
+            if (view().rules().enabled(fixMPTDeliveredAmount) &&
+                amountDeliver != dstAmount)
+                ctx_.deliver(amountDeliver);
+        }
         else if (res == tecINSUFFICIENT_FUNDS || res == tecPATH_DRY)
             res = tecPATH_PARTIAL;