Merge branch 'ximinez/lending-XLS-66-ongoing' into ximinez/lending-XLS-66-test-wip

* XRPLF/ximinez/develop-nolending:
  Revert "Implement Lending Protocol (unsupported) (5270)"
  Implement Lending Protocol (unsupported) (5270)

src/test/app/LendingHelpers_test.cpp

@@ -1,642 +0,0 @@
-#include <xrpl/beast/unit_test/suite.h>
-// DO NOT REMOVE
-#include <test/jtx.h>
-#include <test/jtx/Account.h>
-#include <test/jtx/amount.h>
-#include <test/jtx/mpt.h>
-
-#include <xrpld/app/misc/LendingHelpers.h>
-#include <xrpld/app/misc/LoadFeeTrack.h>
-#include <xrpld/app/tx/detail/Batch.h>
-#include <xrpld/app/tx/detail/LoanSet.h>
-
-#include <xrpl/beast/xor_shift_engine.h>
-#include <xrpl/protocol/SField.h>
-
-#include <string>
-#include <vector>
-
-namespace ripple {
-namespace test {
-
-class LendingHelpers_test : public beast::unit_test::suite
-{
-    void
-    testComputeRaisedRate()
-    {
-        using namespace jtx;
-        using namespace ripple::detail;
-        struct TestCase
-        {
-            std::string name;
-            Number periodicRate;
-            std::uint32_t paymentsRemaining;
-            Number expectedRaisedRate;
-        };
-
-        auto const testCases = std::vector<TestCase>{
-            {
-                .name = "Zero payments remaining",
-                .periodicRate = Number{5, -2},
-                .paymentsRemaining = 0,
-                .expectedRaisedRate = Number{1},  // (1 + r)^0 = 1
-            },
-            {
-                .name = "One payment remaining",
-                .periodicRate = Number{5, -2},
-                .paymentsRemaining = 1,
-                .expectedRaisedRate = Number{105, -2},
-            },  // 1.05^1
-            {
-                .name = "Multiple payments remaining",
-                .periodicRate = Number{5, -2},
-                .paymentsRemaining = 3,
-                .expectedRaisedRate = Number{1157625, -6},
-            },  // 1.05^3
-            {
-                .name = "Zero periodic rate",
-                .periodicRate = Number{0},
-                .paymentsRemaining = 5,
-                .expectedRaisedRate = Number{1},  // (1 + 0)^5 = 1
-            }};
-
-        for (auto const& tc : testCases)
-        {
-            testcase("computeRaisedRate: " + tc.name);
-
-            auto const computedRaisedRate =
-                computeRaisedRate(tc.periodicRate, tc.paymentsRemaining);
-            BEAST_EXPECTS(
-                computedRaisedRate == tc.expectedRaisedRate,
-                "Raised rate mismatch: expected " +
-                    to_string(tc.expectedRaisedRate) + ", got " +
-                    to_string(computedRaisedRate));
-        }
-    }
-
-    void
-    testComputePaymentFactor()
-    {
-        using namespace jtx;
-        using namespace ripple::detail;
-        struct TestCase
-        {
-            std::string name;
-            Number periodicRate;
-            std::uint32_t paymentsRemaining;
-            Number expectedPaymentFactor;
-        };
-
-        auto const testCases = std::vector<TestCase>{
-            {
-                .name = "Zero periodic rate",
-                .periodicRate = Number{0},
-                .paymentsRemaining = 4,
-                .expectedPaymentFactor = Number{25, -2},
-            },  // 1/4 = 0.25
-            {
-                .name = "One payment remaining",
-                .periodicRate = Number{5, -2},
-                .paymentsRemaining = 1,
-                .expectedPaymentFactor = Number{105, -2},
-            },  // 0.05/1 = 1.05
-            {
-                .name = "Multiple payments remaining",
-                .periodicRate = Number{5, -2},
-                .paymentsRemaining = 3,
-                .expectedPaymentFactor = Number{367208564631245, -15},
-            },  // from calc
-            {
-                .name = "Zero payments remaining",
-                .periodicRate = Number{5, -2},
-                .paymentsRemaining = 0,
-                .expectedPaymentFactor = Number{0},
-            }  // edge case
-        };
-
-        for (auto const& tc : testCases)
-        {
-            testcase("computePaymentFactor: " + tc.name);
-
-            auto const computedPaymentFactor =
-                computePaymentFactor(tc.periodicRate, tc.paymentsRemaining);
-            BEAST_EXPECTS(
-                computedPaymentFactor == tc.expectedPaymentFactor,
-                "Payment factor mismatch: expected " +
-                    to_string(tc.expectedPaymentFactor) + ", got " +
-                    to_string(computedPaymentFactor));
-        }
-    }
-
-    void
-    testLoanPeriodicPayment()
-    {
-        using namespace jtx;
-        using namespace ripple::detail;
-
-        struct TestCase
-        {
-            std::string name;
-            Number principalOutstanding;
-            Number periodicRate;
-            std::uint32_t paymentsRemaining;
-            Number expectedPeriodicPayment;
-        };
-
-        auto const testCases = std::vector<TestCase>{
-            {
-                .name = "Zero principal outstanding",
-                .principalOutstanding = Number{0},
-                .periodicRate = Number{5, -2},
-                .paymentsRemaining = 5,
-                .expectedPeriodicPayment = Number{0},
-            },
-            {
-                .name = "Zero payments remaining",
-                .principalOutstanding = Number{1'000},
-                .periodicRate = Number{5, -2},
-                .paymentsRemaining = 0,
-                .expectedPeriodicPayment = Number{0},
-            },
-            {
-                .name = "Zero periodic rate",
-                .principalOutstanding = Number{1'000},
-                .periodicRate = Number{0},
-                .paymentsRemaining = 4,
-                .expectedPeriodicPayment = Number{250},
-            },
-            {
-                .name = "Standard case",
-                .principalOutstanding = Number{1'000},
-                .periodicRate =
-                    loanPeriodicRate(TenthBips32(100'000), 30 * 24 * 60 * 60),
-                .paymentsRemaining = 3,
-                .expectedPeriodicPayment =
-                    Number{3895690663961231, -13},  // from calc
-            },
-        };
-
-        for (auto const& tc : testCases)
-        {
-            testcase("loanPeriodicPayment: " + tc.name);
-
-            auto const computedPeriodicPayment = loanPeriodicPayment(
-                tc.principalOutstanding, tc.periodicRate, tc.paymentsRemaining);
-            BEAST_EXPECTS(
-                computedPeriodicPayment == tc.expectedPeriodicPayment,
-                "Periodic payment mismatch: expected " +
-                    to_string(tc.expectedPeriodicPayment) + ", got " +
-                    to_string(computedPeriodicPayment));
-        }
-    }
-
-    void
-    testLoanPrincipalFromPeriodicPayment()
-    {
-        using namespace jtx;
-        using namespace ripple::detail;
-
-        struct TestCase
-        {
-            std::string name;
-            Number periodicPayment;
-            Number periodicRate;
-            std::uint32_t paymentsRemaining;
-            Number expectedPrincipalOutstanding;
-        };
-
-        auto const testCases = std::vector<TestCase>{
-            {
-                .name = "Zero periodic payment",
-                .periodicPayment = Number{0},
-                .periodicRate = Number{5, -2},
-                .paymentsRemaining = 5,
-                .expectedPrincipalOutstanding = Number{0},
-            },
-            {
-                .name = "Zero payments remaining",
-                .periodicPayment = Number{1'000},
-                .periodicRate = Number{5, -2},
-                .paymentsRemaining = 0,
-                .expectedPrincipalOutstanding = Number{0},
-            },
-            {
-                .name = "Zero periodic rate",
-                .periodicPayment = Number{250},
-                .periodicRate = Number{0},
-                .paymentsRemaining = 4,
-                .expectedPrincipalOutstanding = Number{1'000},
-            },
-            {
-                .name = "Standard case",
-                .periodicPayment = Number{3895690663961231, -13},  // from calc
-                .periodicRate =
-                    loanPeriodicRate(TenthBips32(100'000), 30 * 24 * 60 * 60),
-                .paymentsRemaining = 3,
-                .expectedPrincipalOutstanding = Number{1'000},
-            },
-        };
-
-        for (auto const& tc : testCases)
-        {
-            testcase("loanPrincipalFromPeriodicPayment: " + tc.name);
-
-            auto const computedPrincipalOutstanding =
-                loanPrincipalFromPeriodicPayment(
-                    tc.periodicPayment, tc.periodicRate, tc.paymentsRemaining);
-            BEAST_EXPECTS(
-                computedPrincipalOutstanding == tc.expectedPrincipalOutstanding,
-                "Principal outstanding mismatch: expected " +
-                    to_string(tc.expectedPrincipalOutstanding) + ", got " +
-                    to_string(computedPrincipalOutstanding));
-        }
-    }
-
-    void
-    testComputeOverpaymentComponents()
-    {
-        testcase("computeOverpaymentComponents");
-        using namespace jtx;
-        using namespace ripple::detail;
-
-        Account const issuer{"issuer"};
-        PrettyAsset const IOU = issuer["IOU"];
-        int32_t const loanScale = 1;
-        auto const overpayment = Number{1'000};
-        auto const overpaymentInterestRate = TenthBips32{10'000};  // 10%
-        auto const overpaymentFeeRate = TenthBips32{50'000};       // 50%
-        auto const managementFeeRate = TenthBips16{10'000};        // 10%
-
-        auto const expectedOverpaymentFee = Number{500};  // 50% of 1,000
-        auto const expectedOverpaymentInterestGross =
-            Number{100};  // 10% of 1,000
-        auto const expectedOverpaymentInterestNet =
-            Number{90};  // 100 - 10% of 100
-        auto const expectedOverpaymentManagementFee = Number{10};  // 10% of 100
-        auto const expectedPrincipalPortion = Number{400};  // 1,000 - 100 - 500
-
-        auto const components = detail::computeOverpaymentComponents(
-            IOU,
-            loanScale,
-            overpayment,
-            overpaymentInterestRate,
-            overpaymentFeeRate,
-            managementFeeRate);
-
-        BEAST_EXPECT(
-            components.untrackedManagementFee == expectedOverpaymentFee);
-
-        BEAST_EXPECT(
-            components.untrackedInterest == expectedOverpaymentInterestNet);
-        BEAST_EXPECT(
-            components.trackedManagementFeeDelta ==
-            expectedOverpaymentManagementFee);
-        BEAST_EXPECT(
-            components.trackedPrincipalDelta == expectedPrincipalPortion);
-        BEAST_EXPECT(
-            components.trackedManagementFeeDelta +
-                components.untrackedInterest ==
-            expectedOverpaymentInterestGross);
-
-        BEAST_EXPECT(
-            components.trackedManagementFeeDelta +
-                components.untrackedInterest +
-                components.trackedPrincipalDelta +
-                components.untrackedManagementFee ==
-            overpayment);
-    }
-
-    void
-    testComputeInterestAndFeeParts()
-    {
-        using namespace jtx;
-        using namespace ripple::detail;
-
-        struct TestCase
-        {
-            std::string name;
-            Number interest;
-            TenthBips16 managementFeeRate;
-            Number expectedInterestPart;
-            Number expectedFeePart;
-        };
-
-        Account const issuer{"issuer"};
-        PrettyAsset const IOU = issuer["IOU"];
-        std::int32_t const loanScale = 1;
-
-        auto const testCases = std::vector<TestCase>{
-            {.name = "Zero interest",
-             .interest = Number{0},
-             .managementFeeRate = TenthBips16{10'000},
-             .expectedInterestPart = Number{0},
-             .expectedFeePart = Number{0}},
-            {.name = "Zero fee rate",
-             .interest = Number{1'000},
-             .managementFeeRate = TenthBips16{0},
-             .expectedInterestPart = Number{1'000},
-             .expectedFeePart = Number{0}},
-            {.name = "10% fee rate",
-             .interest = Number{1'000},
-             .managementFeeRate = TenthBips16{10'000},
-             .expectedInterestPart = Number{900},
-             .expectedFeePart = Number{100}},
-        };
-
-        for (auto const& tc : testCases)
-        {
-            testcase("computeInterestAndFeeParts: " + tc.name);
-
-            auto const [computedInterestPart, computedFeePart] =
-                computeInterestAndFeeParts(
-                    IOU, tc.interest, tc.managementFeeRate, loanScale);
-            BEAST_EXPECTS(
-                computedInterestPart == tc.expectedInterestPart,
-                "Interest part mismatch: expected " +
-                    to_string(tc.expectedInterestPart) + ", got " +
-                    to_string(computedInterestPart));
-            BEAST_EXPECTS(
-                computedFeePart == tc.expectedFeePart,
-                "Fee part mismatch: expected " + to_string(tc.expectedFeePart) +
-                    ", got " + to_string(computedFeePart));
-        }
-    }
-
-    void
-    testLoanLatePaymentInterest()
-    {
-        using namespace jtx;
-        using namespace ripple::detail;
-        struct TestCase
-        {
-            std::string name;
-            Number principalOutstanding;
-            TenthBips32 lateInterestRate;
-            NetClock::time_point parentCloseTime;
-            std::uint32_t nextPaymentDueDate;
-            Number expectedLateInterest;
-        };
-
-        auto const testCases = std::vector<TestCase>{
-            {
-                .name = "On-time payment",
-                .principalOutstanding = Number{1'000},
-                .lateInterestRate = TenthBips32{10'000},  // 10%
-                .parentCloseTime =
-                    NetClock::time_point{NetClock::duration{3'000}},
-                .nextPaymentDueDate = 3'000,
-                .expectedLateInterest = Number{0},
-            },
-            {
-                .name = "Early payment",
-                .principalOutstanding = Number{1'000},
-                .lateInterestRate = TenthBips32{10'000},  // 10%
-                .parentCloseTime =
-                    NetClock::time_point{NetClock::duration{3'000}},
-                .nextPaymentDueDate = 4'000,
-                .expectedLateInterest = Number{0},
-            },
-            {
-                .name = "No principal outstanding",
-                .principalOutstanding = Number{0},
-                .lateInterestRate = TenthBips32{10'000},  // 10%
-                .parentCloseTime =
-                    NetClock::time_point{NetClock::duration{3'000}},
-                .nextPaymentDueDate = 2'000,
-                .expectedLateInterest = Number{0},
-            },
-            {
-                .name = "No late interest rate",
-                .principalOutstanding = Number{1'000},
-                .lateInterestRate = TenthBips32{0},  // 0%
-                .parentCloseTime =
-                    NetClock::time_point{NetClock::duration{3'000}},
-                .nextPaymentDueDate = 2'000,
-                .expectedLateInterest = Number{0},
-            },
-            {
-                .name = "Late payment",
-                .principalOutstanding = Number{1'000},
-                .lateInterestRate = TenthBips32{100'000},  // 100%
-                .parentCloseTime =
-                    NetClock::time_point{NetClock::duration{3'000}},
-                .nextPaymentDueDate = 2'000,
-                .expectedLateInterest =
-                    Number{3170979198376459, -17},  // from calc
-            },
-        };
-
-        for (auto const& tc : testCases)
-        {
-            testcase("loanLatePaymentInterest: " + tc.name);
-
-            auto const computedLateInterest = loanLatePaymentInterest(
-                tc.principalOutstanding,
-                tc.lateInterestRate,
-                tc.parentCloseTime,
-                tc.nextPaymentDueDate);
-            BEAST_EXPECTS(
-                computedLateInterest == tc.expectedLateInterest,
-                "Late interest mismatch: expected " +
-                    to_string(tc.expectedLateInterest) + ", got " +
-                    to_string(computedLateInterest));
-        }
-    }
-
-    void
-    testLoanAccruedInterest()
-    {
-        using namespace jtx;
-        using namespace ripple::detail;
-        struct TestCase
-        {
-            std::string name;
-            Number principalOutstanding;
-            Number periodicRate;
-            NetClock::time_point parentCloseTime;
-            std::uint32_t startDate;
-            std::uint32_t prevPaymentDate;
-            std::uint32_t paymentInterval;
-            Number expectedAccruedInterest;
-        };
-
-        auto const testCases = std::vector<TestCase>{
-            {
-                .name = "Zero principal outstanding",
-                .principalOutstanding = Number{0},
-                .periodicRate = Number{5, -2},
-                .parentCloseTime =
-                    NetClock::time_point{NetClock::duration{3'000}},
-                .startDate = 2'000,
-                .prevPaymentDate = 2'500,
-                .paymentInterval = 30 * 24 * 60 * 60,
-                .expectedAccruedInterest = Number{0},
-            },
-            {
-                .name = "Before start date",
-                .principalOutstanding = Number{1'000},
-                .periodicRate = Number{5, -2},
-                .parentCloseTime =
-                    NetClock::time_point{NetClock::duration{1'000}},
-                .startDate = 2'000,
-                .prevPaymentDate = 1'500,
-                .paymentInterval = 30 * 24 * 60 * 60,
-                .expectedAccruedInterest = Number{0},
-            },
-            {
-                .name = "Zero periodic rate",
-                .principalOutstanding = Number{1'000},
-                .periodicRate = Number{0},
-                .parentCloseTime =
-                    NetClock::time_point{NetClock::duration{3'000}},
-                .startDate = 2'000,
-                .prevPaymentDate = 2'500,
-                .paymentInterval = 30 * 24 * 60 * 60,
-                .expectedAccruedInterest = Number{0},
-            },
-            {
-                .name = "Zero payment interval",
-                .principalOutstanding = Number{1'000},
-                .periodicRate = Number{5, -2},
-                .parentCloseTime =
-                    NetClock::time_point{NetClock::duration{3'000}},
-                .startDate = 2'000,
-                .prevPaymentDate = 2'500,
-                .paymentInterval = 0,
-                .expectedAccruedInterest = Number{0},
-            },
-            {
-                .name = "Standard case",
-                .principalOutstanding = Number{1'000},
-                .periodicRate = Number{5, -2},
-                .parentCloseTime =
-                    NetClock::time_point{NetClock::duration{3'000}},
-                .startDate = 1'000,
-                .prevPaymentDate = 2'000,
-                .paymentInterval = 30 * 24 * 60 * 60,
-                .expectedAccruedInterest =
-                    Number{1929012345679012, -17},  // from calc
-            },
-        };
-
-        for (auto const& tc : testCases)
-        {
-            testcase("loanAccruedInterest: " + tc.name);
-
-            auto const computedAccruedInterest = loanAccruedInterest(
-                tc.principalOutstanding,
-                tc.periodicRate,
-                tc.parentCloseTime,
-                tc.startDate,
-                tc.prevPaymentDate,
-                tc.paymentInterval);
-            BEAST_EXPECTS(
-                computedAccruedInterest == tc.expectedAccruedInterest,
-                "Accrued interest mismatch: expected " +
-                    to_string(tc.expectedAccruedInterest) + ", got " +
-                    to_string(computedAccruedInterest));
-        }
-    }
-
-    // This test overlaps with testLoanAccruedInterest, the test cases only
-    // exercise the computeFullPaymentInterest parts unique to it.
-    void
-    testComputeFullPaymentInterest()
-    {
-        using namespace jtx;
-        using namespace ripple::detail;
-
-        struct TestCase
-        {
-            std::string name;
-            Number rawPrincipalOutstanding;
-            Number periodicRate;
-            NetClock::time_point parentCloseTime;
-            std::uint32_t paymentInterval;
-            std::uint32_t prevPaymentDate;
-            std::uint32_t startDate;
-            TenthBips32 closeInterestRate;
-            Number expectedFullPaymentInterest;
-        };
-
-        auto const testCases = std::vector<TestCase>{
-            {
-                .name = "Zero principal outstanding",
-                .rawPrincipalOutstanding = Number{0},
-                .periodicRate = Number{5, -2},
-                .parentCloseTime =
-                    NetClock::time_point{NetClock::duration{3'000}},
-                .paymentInterval = 30 * 24 * 60 * 60,
-                .prevPaymentDate = 2'000,
-                .startDate = 1'000,
-                .closeInterestRate = TenthBips32{10'000},
-                .expectedFullPaymentInterest = Number{0},
-            },
-            {
-                .name = "Zero close interest rate",
-                .rawPrincipalOutstanding = Number{1'000},
-                .periodicRate = Number{5, -2},
-                .parentCloseTime =
-                    NetClock::time_point{NetClock::duration{3'000}},
-                .paymentInterval = 30 * 24 * 60 * 60,
-                .prevPaymentDate = 2'000,
-                .startDate = 1'000,
-                .closeInterestRate = TenthBips32{0},
-                .expectedFullPaymentInterest =
-                    Number{1929012345679012, -17},  // from calc
-            },
-            {
-                .name = "Standard case",
-                .rawPrincipalOutstanding = Number{1'000},
-                .periodicRate = Number{5, -2},
-                .parentCloseTime =
-                    NetClock::time_point{NetClock::duration{3'000}},
-                .paymentInterval = 30 * 24 * 60 * 60,
-                .prevPaymentDate = 2'000,
-                .startDate = 1'000,
-                .closeInterestRate = TenthBips32{10'000},
-                .expectedFullPaymentInterest =
-                    Number{1000192901234568, -13},  // from calc
-            },
-        };
-
-        for (auto const& tc : testCases)
-        {
-            testcase("computeFullPaymentInterest: " + tc.name);
-
-            auto const computedFullPaymentInterest = computeFullPaymentInterest(
-                tc.rawPrincipalOutstanding,
-                tc.periodicRate,
-                tc.parentCloseTime,
-                tc.paymentInterval,
-                tc.prevPaymentDate,
-                tc.startDate,
-                tc.closeInterestRate);
-            BEAST_EXPECTS(
-                computedFullPaymentInterest == tc.expectedFullPaymentInterest,
-                "Full payment interest mismatch: expected " +
-                    to_string(tc.expectedFullPaymentInterest) + ", got " +
-                    to_string(computedFullPaymentInterest));
-        }
-    }
-
-public:
-    void
-    run() override
-    {
-        testComputeFullPaymentInterest();
-        testLoanAccruedInterest();
-        testLoanLatePaymentInterest();
-        testLoanPeriodicPayment();
-        testLoanPrincipalFromPeriodicPayment();
-        testComputeRaisedRate();
-        testComputePaymentFactor();
-        testComputeOverpaymentComponents();
-        testComputeInterestAndFeeParts();
-    }
-};
-
-BEAST_DEFINE_TESTSUITE(LendingHelpers, app, ripple);
-
-}  // namespace test
-}  // namespace ripple

src/test/app/Loan_test.cpp

@@ -521,6 +521,35 @@ protected:
                 .paymentInterval = loan->at(sfPaymentInterval),
                 .interestRate = TenthBips32{loan->at(sfInterestRate)},
             };
+            BEAST_EXPECT(state.previousPaymentDate == 0);
+            BEAST_EXPECT(
+                tp{d{state.nextPaymentDate}} == state.startDate + 600s);
+            BEAST_EXPECT(state.paymentRemaining == 12);
+            BEAST_EXPECT(
+                state.principalOutstanding == broker.asset(loanAmount).value());
+            BEAST_EXPECT(
+                state.loanScale ==
+                (broker.asset.integral()
+                     ? 0
+                     : state.principalOutstanding.exponent()));
+            BEAST_EXPECT(state.paymentInterval == 600);
+            BEAST_EXPECT(
+                state.totalValue ==
+                roundToAsset(
+                    broker.asset,
+                    state.periodicPayment * state.paymentRemaining,
+                    state.loanScale));
+            BEAST_EXPECT(
+                state.managementFeeOutstanding ==
+                computeFee(
+                    broker.asset,
+                    state.totalValue - state.principalOutstanding,
+                    managementFeeRateParameter,
+                    state.loanScale));
+
+            verifyLoanStatus(state);
+
+            return state;
         }
         return LoanState{};
     }
@@ -532,6 +561,7 @@ protected:
         jtx::Env const& env,
         BrokerInfo const& broker,
         Keylet const& loanKeylet,
+        Number const& loanAmount,
         VerifyLoanStatus const& verifyLoanStatus)
     {
         using namespace std::chrono_literals;
@@ -1365,10 +1395,10 @@ protected:
             .counterpartyExplicit = false,
             .principalRequest = loanAmount,
             .setFee = loanSetFee,
-            .originationFee = 1,
-            .serviceFee = 2,
-            .lateFee = 3,
-            .closeFee = 4,
+            .originationFee = loanAmount * Number(1, -3),
+            .serviceFee = loanAmount * Number(2, -3),
+            .lateFee = loanAmount * Number(3, -3),
+            .closeFee = loanAmount * Number(4, -3),
             .overFee = applyExponent(percentageToTenthBips(5) / 10),
             .interest = applyExponent(percentageToTenthBips(12)),
             // 2.4%
@@ -1469,7 +1499,8 @@ protected:
                 loan->at(sfPrincipalOutstanding) == principalRequestAmount);
         }
 
-        auto state = getCurrentState(env, broker, keylet, verifyLoanStatus);
+        auto state =
+            getCurrentState(env, broker, keylet, loanAmount, verifyLoanStatus);
 
         auto const loanProperties = computeLoanProperties(
             broker.asset.raw(),
@@ -1643,8 +1674,8 @@ protected:
         auto const currencyLabel = getCurrencyLabel(asset);
         auto const caseLabel = [&]() {
             std::stringstream ss;
-            ss << "Lifecycle: " << loanAmount << " " << currencyLabel
-               << " Scale interest to: " << interestExponent << " ";
+            ss << "Lifecycle: " << " " << currencyLabel << " Interest scale: "
+               << Number(1, interestExponent) " Amount: " << loanAmount;
             return ss.str();
         }();
         testcase << caseLabel;
@@ -2145,8 +2176,8 @@ protected:
                 // Default the loan
 
                 // Initialize values with the current state
-                auto state =
-                    getCurrentState(env, broker, loanKeylet, verifyLoanStatus);
+                auto state = getCurrentState(
+                    env, broker, loanKeylet, loanAmount, verifyLoanStatus);
                 BEAST_EXPECT(state.flags == baseFlag);
 
                 auto const& broker = verifyLoanStatus.broker;
@@ -2374,8 +2405,9 @@ protected:
                        VerifyLoanStatus const& verifyLoanStatus) {
                 // toEndOfLife
                 //
-                auto state =
-                    getCurrentState(env, broker, loanKeylet, verifyLoanStatus);
+                auto state = getCurrentState(
+                    env, broker, loanKeylet, loanAmount, verifyLoanStatus);
+                BEAST_EXPECT(state.flags == baseFlag);
                 env.close(state.startDate + 20s);
                 auto const loanAge = (env.now() - state.startDate).count();
                 BEAST_EXPECT(loanAge == 30);
@@ -2402,22 +2434,38 @@ protected:
                         interval};
                 BEAST_EXPECT(
                     accruedInterest ==
-                    broker.asset(Number(1141552511415525, -19)));
+                    broker.asset(loanAmount * Number(1141552511415525, -22)));
                 STAmount const prepaymentPenalty{
-                    broker.asset, state.principalOutstanding * Number(36, -3)};
-                BEAST_EXPECT(prepaymentPenalty == broker.asset(36));
-                STAmount const closePaymentFee = broker.asset(4);
+                    broker.asset,
+                    state.principalOutstanding *
+                        Number(36, interestExponent - 3)};
+                BEAST_EXPECT(
+                    prepaymentPenalty ==
+                    broker.asset(
+                        loanAmount * Number(36, interestExponent - 3)));
+                STAmount const closePaymentFee =
+                    broker.asset(loanAmount * Number(4, -3));
                 auto const payoffAmount = roundToScale(
                     principalOutstanding + accruedInterest + prepaymentPenalty +
                         closePaymentFee,
                     state.loanScale);
+                // TODO: Figure out what's wrong with this calculation
+                // STAmount{broker.asset, state.principalOutstanding} +
+                // accruedInterest + prepaymentPenalty + closePaymentFee;
                 BEAST_EXPECT(
                     payoffAmount ==
                     roundToAsset(
                         broker.asset,
-                        broker.asset(Number(1040000114155251, -12)).number(),
+                        broker.asset(loanAmount * Number(1040000114155251, -15))
+                            .number(),
                         state.loanScale));
 
+                // Try to pay a little extra to show that it's _not_
+                // taken
+                auto const transactionAmount =
+                    payoffAmount + broker.asset(loanAmount * Number(1, -2));
+                env(pay(borrower, loanKeylet.key, transactionAmount));
+
                 // The terms of this loan actually make the early payoff
                 // more expensive than just making payments
                 BEAST_EXPECT(
@@ -2601,8 +2649,8 @@ protected:
                 // toEndOfLife
                 //
                 // Draw and make multiple payments
-                auto state =
-                    getCurrentState(env, broker, loanKeylet, verifyLoanStatus);
+                auto state = getCurrentState(
+                    env, broker, loanKeylet, loanAmount, verifyLoanStatus);
                 BEAST_EXPECT(state.flags == 0);
                 env.close();
 
@@ -2714,6 +2762,21 @@ protected:
 
                 while (state.paymentRemaining > 0)
                 {
+                    // Try to pay a little extra to show that it's _not_
+                    // taken
+                    STAmount const transactionAmount =
+                        STAmount{broker.asset, totalDue} +
+                        broker.asset(loanAmount * Number(1, -2));
+                    // Only check the first payment since the rounding may
+                    // drift as payments are made
+                    BEAST_EXPECT(
+                        transactionAmount ==
+                        roundToScale(
+                            broker.asset(
+                                Number(9533457001162141, -14), Number::upward),
+                            state.loanScale,
+                            Number::upward));
+
                     // Compute the expected principal amount
                     auto const paymentComponents =
                         detail::computePaymentComponents(
@@ -2795,7 +2858,7 @@ protected:
                             Number::upward) ==
                             roundToScale(
                                 broker.asset(
-                                    Number(8333228695260180, -14),
+                                    loanAmount * Number(8333228695260180, -17),
                                     Number::upward),
                                 state.loanScale,
                                 Number::upward));
@@ -2907,6 +2970,10 @@ protected:
                     ter(tecNO_PERMISSION));
                 env(manage(lender, loanKeylet.key, tfLoanDefault),
                     ter(tecNO_PERMISSION));
+
+                // Can't make a payment on it either
+                env(pay(borrower, loanKeylet.key, broker.asset(loanAmount)),
+                    ter(tecKILLED));
             });
 
 #if LOANTODO
@@ -3649,19 +3716,23 @@ protected:
         // Create and update Loans
         for (auto const& broker : brokers)
         {
-            for (int amountExponent = 3; amountExponent >= 3; --amountExponent)
+            for (int amountMantissa : {1, 3, 7})
             {
-                Number const loanAmount{1, amountExponent};
-                for (int interestExponent = 0; interestExponent >= 0;
-                     --interestExponent)
+                for (int amountExponent = 3; amountExponent >= -5;
+                     amountExponent -= 4)
                 {
-                    testCaseWrapper(
-                        env,
-                        mptt,
-                        assets,
-                        broker,
-                        loanAmount,
-                        interestExponent);
+                    Number const loanAmount{amountMantissa, amountExponent};
+                    for (int interestExponent = 1 - 1; interestExponent >= -2;
+                         --interestExponent)
+                    {
+                        testCaseWrapper(
+                            env,
+                            mptt,
+                            assets,
+                            broker,
+                            loanAmount,
+                            interestExponent);
+                    }
                 }
             }
 
@@ -6145,16 +6216,15 @@ protected:
         // Accrued + prepayment-penalty interest based on current periodic
         // schedule
         auto const fullPaymentInterest = computeFullPaymentInterest(
-            detail::loanPrincipalFromPeriodicPayment(
-                after.periodicPayment, periodicRate2, after.paymentRemaining),
+            after.periodicPayment,
             periodicRate2,
+            after.paymentRemaining,
             env.current()->parentCloseTime(),
             after.paymentInterval,
             after.previousPaymentDate,
             static_cast<std::uint32_t>(
                 after.startDate.time_since_epoch().count()),
             closeInterestRate);
-
         // Round to asset scale and split interest/fee parts
         auto const roundedInterest =
             roundToAsset(asset.raw(), fullPaymentInterest, after.loanScale);
@@ -6182,9 +6252,9 @@ protected:
         // window by clamping prevPaymentDate to 'now' for the full-pay path.
         auto const prevClamped = std::min(after.previousPaymentDate, nowSecs);
         auto const fullPaymentInterestClamped = computeFullPaymentInterest(
-            detail::loanPrincipalFromPeriodicPayment(
-                after.periodicPayment, periodicRate2, after.paymentRemaining),
+            after.periodicPayment,
             periodicRate2,
+            after.paymentRemaining,
             env.current()->parentCloseTime(),
             after.paymentInterval,
             prevClamped,

src/test/app/Vault_test.cpp

@@ -5243,46 +5243,6 @@ class Vault_test : public beast::unit_test::suite
         });
     }
 
-    void
-    testFrozenWithdrawToIssuer()
-    {
-        using namespace test::jtx;
-
-        testcase("frozen asset cannot withdraw to issuer (spec deviation)");
-
-        Env env{*this, testable_amendments() | featureSingleAssetVault};
-        Account issuer{"issuer"};
-        Account owner{"owner"};
-        Account depositor{"depositor"};
-        env.fund(XRP(1000), issuer, owner, depositor);
-        env.close();
-
-        PrettyAsset asset = issuer["IOU"];
-        env.trust(asset(1000), owner);
-        env.trust(asset(1000), depositor);
-        env(pay(issuer, owner, asset(100)));
-        env(pay(issuer, depositor, asset(200)));
-        env.close();
-
-        Vault vault{env};
-        auto [tx, keylet] = vault.create({.owner = owner, .asset = asset});
-        env(tx);
-        env.close();
-
-        env(vault.deposit(
-            {.depositor = depositor, .id = keylet.key, .amount = asset(50)}));
-        env.close();
-
-        env(fset(issuer, asfGlobalFreeze));
-        env.close();
-
-        auto withdraw = vault.withdraw(
-            {.depositor = depositor, .id = keylet.key, .amount = asset(10)});
-        withdraw[sfDestination] = issuer.human();
-        env(withdraw, ter{tesSUCCESS});
-        env.close();
-    }
-
 public:
     void
     run() override
@@ -5301,7 +5261,6 @@ public:
         testScaleIOU();
         testRPC();
         testDelegate();
-        testFrozenWithdrawToIssuer();
     }
 };
 

src/xrpld/app/misc/LendingHelpers.h

@@ -202,6 +202,14 @@ computeRawLoanState(
     std::uint32_t const paymentRemaining,
     TenthBips32 const managementFeeRate);
 
+LoanState
+computeRawLoanState(
+    Number const& periodicPayment,
+    TenthBips32 interestRate,
+    std::uint32_t paymentInterval,
+    std::uint32_t const paymentRemaining,
+    TenthBips32 const managementFeeRate);
+
 // Constructs a valid LoanState object from arbitrary inputs
 LoanState
 constructLoanState(
@@ -231,6 +239,17 @@ computeFullPaymentInterest(
     std::uint32_t startDate,
     TenthBips32 closeInterestRate);
 
+Number
+computeFullPaymentInterest(
+    Number const& periodicPayment,
+    Number const& periodicRate,
+    std::uint32_t paymentRemaining,
+    NetClock::time_point parentCloseTime,
+    std::uint32_t paymentInterval,
+    std::uint32_t prevPaymentDate,
+    std::uint32_t startDate,
+    TenthBips32 closeInterestRate);
+
 namespace detail {
 // These classes and functions should only be accessed by LendingHelper
 // functions and unit tests
@@ -368,58 +387,6 @@ struct LoanStateDeltas
     nonNegative();
 };
 
-Number
-computeRaisedRate(Number const& periodicRate, std::uint32_t paymentsRemaining);
-
-Number
-computePaymentFactor(
-    Number const& periodicRate,
-    std::uint32_t paymentsRemaining);
-
-std::pair<Number, Number>
-computeInterestAndFeeParts(
-    Asset const& asset,
-    Number const& interest,
-    TenthBips16 managementFeeRate,
-    std::int32_t loanScale);
-
-Number
-loanPeriodicPayment(
-    Number const& principalOutstanding,
-    Number const& periodicRate,
-    std::uint32_t paymentsRemaining);
-
-Number
-loanPrincipalFromPeriodicPayment(
-    Number const& periodicPayment,
-    Number const& periodicRate,
-    std::uint32_t paymentsRemaining);
-
-Number
-loanLatePaymentInterest(
-    Number const& principalOutstanding,
-    TenthBips32 lateInterestRate,
-    NetClock::time_point parentCloseTime,
-    std::uint32_t nextPaymentDueDate);
-
-Number
-loanAccruedInterest(
-    Number const& principalOutstanding,
-    Number const& periodicRate,
-    NetClock::time_point parentCloseTime,
-    std::uint32_t startDate,
-    std::uint32_t prevPaymentDate,
-    std::uint32_t paymentInterval);
-
-ExtendedPaymentComponents
-computeOverpaymentComponents(
-    Asset const& asset,
-    int32_t const loanScale,
-    Number const& overpayment,
-    TenthBips32 const overpaymentInterestRate,
-    TenthBips32 const overpaymentFeeRate,
-    TenthBips16 const managementFeeRate);
-
 PaymentComponents
 computePaymentComponents(
     Asset const& asset,

src/xrpld/app/misc/detail/LendingHelpers.cpp

@@ -100,9 +100,6 @@ computePaymentFactor(
     Number const& periodicRate,
     std::uint32_t paymentsRemaining)
 {
-    if (paymentsRemaining == 0)
-        return numZero;
-
     // For zero interest, payment factor is simply 1/paymentsRemaining
     if (periodicRate == beast::zero)
         return Number{1} / paymentsRemaining;
@@ -135,6 +132,27 @@ loanPeriodicPayment(
         computePaymentFactor(periodicRate, paymentsRemaining);
 }
 
+/* Calculates the periodic payment amount from annualized interest rate.
+ * Converts the annual rate to periodic rate before computing payment.
+ *
+ * Equation (7) from XLS-66 spec, Section A-2 Equation Glossary
+ */
+Number
+loanPeriodicPayment(
+    Number const& principalOutstanding,
+    TenthBips32 interestRate,
+    std::uint32_t paymentInterval,
+    std::uint32_t paymentsRemaining)
+{
+    if (principalOutstanding == 0 || paymentsRemaining == 0)
+        return 0;
+
+    Number const periodicRate = loanPeriodicRate(interestRate, paymentInterval);
+
+    return loanPeriodicPayment(
+        principalOutstanding, periodicRate, paymentsRemaining);
+}
+
 /* Reverse-calculates principal from periodic payment amount.
  * Used to determine theoretical principal at any point in the schedule.
  *
@@ -146,9 +164,6 @@ loanPrincipalFromPeriodicPayment(
     Number const& periodicRate,
     std::uint32_t paymentsRemaining)
 {
-    if (paymentsRemaining == 0)
-        return numZero;
-
     if (periodicRate == 0)
         return periodicPayment * paymentsRemaining;
 
@@ -156,6 +171,21 @@ loanPrincipalFromPeriodicPayment(
         computePaymentFactor(periodicRate, paymentsRemaining);
 }
 
+/* Splits gross interest into net interest (to vault) and management fee (to
+ * broker). Returns pair of (net interest, management fee).
+ *
+ * Equation (33) from XLS-66 spec, Section A-2 Equation Glossary
+ */
+std::pair<Number, Number>
+computeInterestAndFeeParts(
+    Number const& interest,
+    TenthBips16 managementFeeRate)
+{
+    auto const fee = tenthBipsOfValue(interest, managementFeeRate);
+
+    return std::make_pair(interest - fee, fee);
+}
+
 /*
  * Computes the interest and management fee parts from interest amount.
  *
@@ -186,12 +216,6 @@ loanLatePaymentInterest(
     NetClock::time_point parentCloseTime,
     std::uint32_t nextPaymentDueDate)
 {
-    if (principalOutstanding == beast::zero)
-        return numZero;
-
-    if (lateInterestRate == TenthBips32{0})
-        return numZero;
-
     auto const now = parentCloseTime.time_since_epoch().count();
 
     // If the payment is not late by any amount of time, then there's no late
@@ -224,9 +248,6 @@ loanAccruedInterest(
     if (periodicRate == beast::zero)
         return numZero;
 
-    if (paymentInterval == 0)
-        return numZero;
-
     auto const lastPaymentDate = std::max(prevPaymentDate, startDate);
     auto const now = parentCloseTime.time_since_epoch().count();
 
@@ -1204,12 +1225,17 @@ computeOverpaymentComponents(
     // This interest doesn't follow the normal amortization schedule - it's
     // a one-time charge for paying early.
     // Equation (20) and (21) from XLS-66 spec, Section A-2 Equation Glossary
+    auto const [rawOverpaymentInterest, _] = [&]() {
+        Number const interest =
+            tenthBipsOfValue(overpayment, overpaymentInterestRate);
+        return detail::computeInterestAndFeeParts(interest, managementFeeRate);
+    }();
+
+    // Round the penalty interest components to the loan scale
     auto const [roundedOverpaymentInterest, roundedOverpaymentManagementFee] =
         [&]() {
-            auto const interest = roundToAsset(
-                asset,
-                tenthBipsOfValue(overpayment, overpaymentInterestRate),
-                loanScale);
+            Number const interest =
+                roundToAsset(asset, rawOverpaymentInterest, loanScale);
             return detail::computeInterestAndFeeParts(
                 asset, interest, managementFeeRate, loanScale);
         }();
@@ -1403,6 +1429,31 @@ computeFullPaymentInterest(
     return accruedInterest + prepaymentPenalty;
 }
 
+Number
+computeFullPaymentInterest(
+    Number const& periodicPayment,
+    Number const& periodicRate,
+    std::uint32_t paymentRemaining,
+    NetClock::time_point parentCloseTime,
+    std::uint32_t paymentInterval,
+    std::uint32_t prevPaymentDate,
+    std::uint32_t startDate,
+    TenthBips32 closeInterestRate)
+{
+    Number const rawPrincipalOutstanding =
+        detail::loanPrincipalFromPeriodicPayment(
+            periodicPayment, periodicRate, paymentRemaining);
+
+    return computeFullPaymentInterest(
+        rawPrincipalOutstanding,
+        periodicRate,
+        parentCloseTime,
+        paymentInterval,
+        prevPaymentDate,
+        startDate,
+        closeInterestRate);
+}
+
 /* Calculates the theoretical loan state at maximum precision for a given point
  * in the amortization schedule.
  *
@@ -1464,6 +1515,21 @@ computeRawLoanState(
         .managementFeeDue = rawManagementFeeOutstanding};
 };
 
+LoanState
+computeRawLoanState(
+    Number const& periodicPayment,
+    TenthBips32 interestRate,
+    std::uint32_t paymentInterval,
+    std::uint32_t const paymentRemaining,
+    TenthBips32 const managementFeeRate)
+{
+    return computeRawLoanState(
+        periodicPayment,
+        loanPeriodicRate(interestRate, paymentInterval),
+        paymentRemaining,
+        managementFeeRate);
+}
+
 /* Constructs a LoanState from rounded Loan ledger object values.
  *
  * This function creates a LoanState structure from the three tracked values

src/xrpld/app/tx/detail/LoanBrokerDelete.cpp

@@ -67,7 +67,7 @@ LoanBrokerDelete::preclaim(PreclaimContext const& ctx)
             JLOG(ctx.j.warn()) << "LoanBrokerDelete: Debt total is "
                                << debtTotal << ", which rounds to " << rounded;
             return tecHAS_OBLIGATIONS;
-            // LCOV_EXCL_STOP
+            // LCOV_EXCL_START
         }
     }
 

src/xrpld/app/tx/detail/VaultWithdraw.cpp

@@ -80,23 +80,13 @@ VaultWithdraw::preclaim(PreclaimContext const& ctx)
         return ter;
 
     // Cannot withdraw from a Vault an Asset frozen for the destination account
-    if (!vaultAsset.holds<Issue>() ||
-        (dstAcct != vaultAsset.getIssuer() &&
-         account != vaultAsset.getIssuer()))
-    {
-        if (auto const ret = checkFrozen(ctx.view, dstAcct, vaultAsset))
-            return ret;
-    }
+    if (auto const ret = checkFrozen(ctx.view, dstAcct, vaultAsset))
+        return ret;
 
     // Cannot return shares to the vault, if the underlying asset was frozen for
     // the submitter
-    if (!vaultAsset.holds<Issue>() ||
-        (dstAcct != vaultAsset.getIssuer() &&
-         account != vaultAsset.getIssuer()))
-    {
-        if (auto const ret = checkFrozen(ctx.view, account, vaultShare))
-            return ret;
-    }
+    if (auto const ret = checkFrozen(ctx.view, account, vaultShare))
+        return ret;
 
     return tesSUCCESS;
 }
@@ -125,7 +115,6 @@ VaultWithdraw::doApply()
 
     auto const amount = ctx_.tx[sfAmount];
     Asset const vaultAsset = vault->at(sfAsset);
-    auto const dstAcct = ctx_.tx[~sfDestination].value_or(account_);
     MPTIssue const share{mptIssuanceID};
     STAmount sharesRedeemed = {share};
     STAmount assetsWithdrawn;
@@ -176,20 +165,11 @@ VaultWithdraw::doApply()
         return tecPATH_DRY;
     }
 
-    // When withdrawing IOU to the issuer, ignore freeze since spec allows
-    // returning frozen IOU assets to their issuer (MPTs don't have this
-    // concept)
-    FreezeHandling const freezeHandling = (vaultAsset.holds<Issue>() &&
-                                           (dstAcct == vaultAsset.getIssuer() ||
-                                            account_ == vaultAsset.getIssuer()))
-        ? FreezeHandling::fhIGNORE_FREEZE
-        : FreezeHandling::fhZERO_IF_FROZEN;
-
     if (accountHolds(
             view(),
             account_,
             share,
-            freezeHandling,
+            FreezeHandling::fhZERO_IF_FROZEN,
             AuthHandling::ahIGNORE_AUTH,
             j_) < sharesRedeemed)
     {
@@ -257,6 +237,8 @@ VaultWithdraw::doApply()
         // else quietly ignore, account balance is not zero
     }
 
+    auto const dstAcct = ctx_.tx[~sfDestination].value_or(account_);
+
     return doWithdraw(
         view(),
         ctx_.tx,