VaultBugs_test.cpp

#include <test/app/vault/VaultTestBase.h>
#include <test/jtx/Account.h>
#include <test/jtx/CaptureLogs.h>
#include <test/jtx/Env.h>
#include <test/jtx/TestHelpers.h>
#include <test/jtx/amount.h>
#include <test/jtx/credentials.h>
#include <test/jtx/fee.h>
#include <test/jtx/flags.h>
#include <test/jtx/mpt.h>
#include <test/jtx/pay.h>
#include <test/jtx/permissioned_domains.h>
#include <test/jtx/sig.h>
#include <test/jtx/sponsor.h>
#include <test/jtx/ter.h>
#include <test/jtx/trust.h>
#include <test/jtx/vault.h>
 
#include <xrpl/basics/Number.h>
#include <xrpl/basics/base_uint.h>
#include <xrpl/basics/chrono.h>
#include <xrpl/beast/unit_test/suite.h>
#include <xrpl/json/json_forwards.h>
#include <xrpl/json/json_value.h>
#include <xrpl/ledger/helpers/VaultHelpers.h>
#include <xrpl/protocol/Asset.h>
#include <xrpl/protocol/Feature.h>
#include <xrpl/protocol/Indexes.h>
#include <xrpl/protocol/Issue.h>
#include <xrpl/protocol/Keylet.h>
#include <xrpl/protocol/MPTIssue.h>
#include <xrpl/protocol/Protocol.h>
#include <xrpl/protocol/SField.h>
#include <xrpl/protocol/STAmount.h>
#include <xrpl/protocol/STNumber.h>  // IWYU pragma: keep
#include <xrpl/protocol/SeqProxy.h>
#include <xrpl/protocol/TER.h>
#include <xrpl/protocol/TxFlags.h>
#include <xrpl/protocol/UintTypes.h>
 
#include <chrono>
#include <cstdint>
#include <memory>
#include <optional>
#include <string>
#include <tuple>
#include <utility>
 
namespace xrpl {
 
class VaultBugs_test : public VaultTestBase
{
private:
    // Bug: the equality check (vault outflow == destination inflow) was
    // skipped whenever the destination delta rounded to zero at localMinScale,
    // including cases where the vault outflow rounded to a non-zero value and
    // a representable amount of value was genuinely destroyed.
    //
    // Scenario: Bob's IOU balance sits 5 units below the 10^16 STAmount
    // precision boundary (atEdge2 = 9,999,999,999,999,995).  A withdrawal of
    // 6 USD shifts his balance across that boundary: the exponent increments
    // (0 → 1), so his effective inflow in Number space is only +5 — 1 USD is
    // consumed by the precision-boundary rounding and cannot be credited.
    //
    // The destroyed amount (1 USD) is sub-ULP at destinationScale=1 (step=10),
    // so the check treats it as an unavoidable IOU-precision artefact and
    // lets the transaction succeed.
    //
    // Contrast: if 15 USD were destroyed at the same scale (destroyed ≥ step),
    // floor(15/10)=1 ≠ 0 and the invariant would fire — that discrepancy IS
    // representable and indicates a real accounting bug.
    //
    // Pre-fixCleanup3_2_0: the "must increase destination balance" check fires
    // because roundedDestinationDelta = 0 ≤ 0.
    void
    testVaultWithdrawEqualityEnforced()
    {
        using namespace test::jtx;
 
        auto runScenario = [this](FeatureBitset features, TER expected) {
            std::string logs;
            Env env(*this, features, std::make_unique<test::CaptureLogs>(&logs));
 
            Account const issuer{"issuer"};
            Account const alice{"alice"};
            Account const bob{"bob"};
 
            env.fund(XRP(100'000), issuer, alice, bob);
            env.close();
            env(fset(issuer, asfDefaultRipple));
            env.close();
 
            PrettyAsset const usd{issuer["USD"]};
            STAmount const aliceLimit{usd.raw(), 2, 16};
            STAmount const bobLimit{usd.raw(), 2, 16};
            // Bob's balance sits 5 units below the 10^16 STAmount precision
            // boundary.  Receiving 6 USD shifts his exponent 0 → 1; the
            // STAmount records +5, not +6 (1 USD is lost to rounding).
            STAmount const atEdge2{usd.raw(), Number{9'999'999'999'999'995LL}};
 
            env(trust(alice, aliceLimit));
            env(trust(bob, bobLimit));
            env.close();
 
            env(pay(issuer, alice, usd(1'000)));
            env(pay(issuer, bob, atEdge2));
            env.close();
 
            Vault const vault{env};
            auto [vaultTx, vaultKeylet] = vault.create({.owner = alice, .asset = usd});
            vaultTx[sfScale] = 0;
            env(vaultTx);
            env.close();
 
            env(vault.deposit({.depositor = alice, .id = vaultKeylet.key, .amount = usd(1'000)}));
            env.close();
 
            // Withdraw 6 USD to Bob: vault loses 6, Bob gains only 5.
            // Destroyed amount = 1 USD, which is sub-ULP at destinationScale=1.
            auto tx = vault.withdraw({.depositor = alice, .id = vaultKeylet.key, .amount = usd(6)});
            tx[sfDestination] = bob.human();
            env(tx, Ter(expected));
            env.close();
        };
 
        {
            testcase(
                "bug: VaultWithdraw to destination at IOU precision boundary fires "
                "invariant (pre-fixCleanup3_2_0)");
            runScenario(testableAmendments() - fixCleanup3_2_0, tecINVARIANT_FAILED);
        }
        {
            testcase(
                "bug: VaultWithdraw to destination at IOU precision boundary succeeds "
                "when destroyed amount is sub-ULP (post-fixCleanup3_2_0)");
            runScenario(testableAmendments(), tesSUCCESS);
        }
    }
 
    // VaultDeposit by issuer with the vault parked at the IOU 16-digit
    // edge (9.999e15). Issuer mints 2 more USD; the vault trust line
    // goes 9.999e15 → 10^16, gaining 1 unit instead of 2 (canonicalization).
    //
    // Pre-fixCleanup3_2_0: the proactive check is absent; the deposit
    // applies, then VaultInvariant's "deposit must increase vault
    // balance" assertion fires at finalize time on the rounded vault
    // delta of zero, returning tecINVARIANT_FAILED.
    // Post-amendment: reject deposit that is not representable at Vault scale.
    void
    testBugIssuerVaultDepositAtEdge()
    {
        using namespace test::jtx;
 
        auto runScenario = [this](FeatureBitset features, TER expected) {
            std::string logs;
            Env env(*this, features, std::make_unique<test::CaptureLogs>(&logs));
 
            Account const issuer{"issuer"};
            Account const owner{"owner"};
 
            env.fund(XRP(100'000), issuer, owner);
            env.close();
            env(fset(issuer, asfDefaultRipple));
            env.close();
 
            PrettyAsset const usd{issuer["USD"]};
            STAmount const trustLimit{usd.raw(), 2, 16};
            STAmount const ownerFund{usd.raw(), Number{9'999'999'999'999'999LL}};
 
            env(trust(owner, trustLimit));
            env.close();
            env(pay(issuer, owner, ownerFund));
            env.close();
 
            Vault const vault{env};
            auto [vaultTx, vaultKeylet] = vault.create({.owner = owner, .asset = usd});
            vaultTx[sfScale] = 0;
            env(vaultTx);
            env.close();
            env(vault.deposit({.depositor = owner, .id = vaultKeylet.key, .amount = ownerFund}));
            env.close();
 
            // Vault pseudo-account is now at 9.999e15. Issuer mints 2
            // more USD. Pre: tecINVARIANT_FAILED at finalize. Post:
            // tecPRECISION_LOSS proactively. Either way, no value moves.
            env(vault.deposit({.depositor = issuer, .id = vaultKeylet.key, .amount = usd(2)}),
                Ter(expected));
            env.close();
        };
 
        {
            testcase(
                "bug: VaultDeposit by issuer at IOU edge fires "
                "tecINVARIANT_FAILED at finalize (pre-fixCleanup3_2_0)");
            runScenario(testableAmendments() - fixCleanup3_2_0, tecINVARIANT_FAILED);
        }
        {
            testcase(
                "bug: VaultDeposit by issuer at IOU edge rejects with "
                "tecPRECISION_LOSS proactively (post-fixCleanup3_2_0)");
            runScenario(testableAmendments(), tecPRECISION_LOSS);
        }
    }
 
    // Bug: DeltaInfo::makeDelta uses max(scale(after), scale(before)) for
    // sfAssetsTotal/Available deltas.  This is symmetric to
    // testBugMakeDeltaAnteriorScale but in the opposite direction: a deposit
    // pushes assetsTotal from just below 1e16 (IOU exponent 0, ULP = 1) to just
    // above it (exponent 1, ULP = 10).  makeDelta picks the coarser *posterior*
    // scale 1.  The trust line balance rounds from atEdge + 2 = 10,000,000,000,000,001
    // → 1e16, so the pseudo-account delta is only +1 in IOU space.
    // roundToAsset(+1, scale=1) = 0 fires "deposit must increase vault balance"
    // even though the state change is consistent at every precision boundary.
    //
    // Fix (fixCleanup3_2_0): computeVaultMinScale uses the posterior Number-space
    // scale of sfAssetsTotal (which retains the full value 10,000,000,000,000,001,
    // exponent 0), giving minScale = 0.  roundToAsset(+1, scale=0) = 1 > 0 and
    // the invariant passes.  However the transactor's own precision guard fires
    // first (bob pays 2 USD, vault receives only 1 due to IOU rounding), so the
    // post-amendment result is tecPRECISION_LOSS rather than tesSUCCESS —
    // the depositor is protected from silently losing 1 USD to rounding.
    void
    testBugMakeDeltaPosteriorScale()
    {
        using namespace test::jtx;
 
        auto runScenario = [this](FeatureBitset features, TER expected) {
            std::string logs;
            Env env(*this, features, std::make_unique<test::CaptureLogs>(&logs));
 
            Account const issuer{"issuer"};
            Account const alice{"alice"};
            Account const bob{"bob"};
 
            env.fund(XRP(100'000), issuer, alice, bob);
            env.close();
            env(fset(issuer, asfDefaultRipple));
            env.close();
 
            PrettyAsset const usd{issuer["USD"]};
            // atEdge is the largest IOU value with exponent 0 (ULP = 1).
            // A deposit of 2 USD brings assetsTotal to 10,000,000,000,000,001
            // in Number space, crossing the 1e16 boundary in IOU space.
            STAmount const atEdge{usd.raw(), Number{9'999'999'999'999'999LL}};
 
            env(trust(alice, STAmount{usd.raw(), 2, 16}));
            env(trust(bob, usd(100)));
            env.close();
            env(pay(issuer, alice, atEdge));
            env(pay(issuer, bob, usd(2)));
            env.close();
 
            Vault const vault{env};
            auto [vaultTx, vaultKeylet] = vault.create({.owner = alice, .asset = usd});
            vaultTx[sfScale] = 0;
            env(vaultTx);
            env.close();
 
            // sfAssetsTotal = sfAssetsAvailable = atEdge (exponent 0, ULP = 1)
            env(vault.deposit({.depositor = alice, .id = vaultKeylet.key, .amount = atEdge}));
            env.close();
 
            // Deposit 2 USD: +2 is sub-ULP at the posterior IOU scale (ULP = 10)
            // but exact at the Number scale retained by sfAssetsTotal.
            env(vault.deposit({.depositor = bob, .id = vaultKeylet.key, .amount = usd(2)}),
                Ter(expected));
            env.close();
        };
 
        {
            testcase(
                "bug: VaultDeposit across IOU scale boundary fires invariant "
                "(pre-fixCleanup3_2_0)");
            runScenario(testableAmendments() - fixCleanup3_2_0, tecINVARIANT_FAILED);
        }
        {
            testcase(
                "bug: VaultDeposit across IOU scale boundary succeeds "
                "(post-fixCleanup3_2_0)");
            runScenario(testableAmendments(), tecPRECISION_LOSS);
        }
    }
 
    // Bug: DeltaInfo::makeDelta uses max(scale(after), scale(before)) for the
    // sfAssetsTotal and sfAssetsAvailable deltas, and visitEntry applies the
    // same max() for the vault pseudo-account RippleState.  When
    // sfAssetsTotal sits exactly at 1e16 (IOU exponent 1, ULP = 10) and a
    // withdrawal of 5 USD brings it to 9.999...995e15 (IOU exponent 0,
    // ULP = 1), all three computations pick the anterior coarser scale 1.
    // roundToAsset(-5, scale=1) collapses to 0, so the invariant check
    // vaultPseudoDeltaAssets >= kZero fires even though the state change is
    // valid and fully consistent at IOU precision.
    //
    // Fix (fixCleanup3_2_0): finalize compares the vault pseudo-account and
    // sfAssetsTotal/Available deltas directly in Number space, bypassing
    // scale-coarsened rounding.
    void
    testBugMakeDeltaAnteriorScale()
    {
        using namespace test::jtx;
 
        auto runScenario = [this](FeatureBitset features, TER expected) {
            std::string logs;
            Env env(*this, features, std::make_unique<test::CaptureLogs>(&logs));
 
            Account const issuer{"issuer"};
            Account const alice{"alice"};
 
            env.fund(XRP(100'000), issuer, alice);
            env.close();
            env(fset(issuer, asfDefaultRipple));
            env.close();
 
            PrettyAsset const usd{issuer["USD"]};
            // Trust limit of 2e16, fund exactly 1e16 so deposit lands at the
            // IOU scale-1 boundary (exponent 1, ULP = 10).
            STAmount const fundAndDeposit{usd.raw(), Number{1, 16}};
 
            env(trust(alice, STAmount{usd.raw(), 2, 16}));
            env.close();
            env(pay(issuer, alice, fundAndDeposit));
            env.close();
 
            Vault const vault{env};
            auto [vaultTx, vaultKeylet] = vault.create({.owner = alice, .asset = usd});
            vaultTx[sfScale] = 0;
            env(vaultTx);
            env.close();
 
            // sfAssetsTotal = sfAssetsAvailable = 1e16 (exponent 1, ULP = 10).
            env(vault.deposit(
                {.depositor = alice, .id = vaultKeylet.key, .amount = fundAndDeposit}));
            env.close();
 
            // Withdraw 5 USD: -5 is sub-ULP at the anterior scale (ULP = 10)
            // but exact at the posterior scale (ULP = 1).  The state change is
            // consistent; only the invariant's scale selection is wrong.
            env(vault.withdraw({.depositor = alice, .id = vaultKeylet.key, .amount = usd(5)}),
                Ter(expected));
            env.close();
        };
 
        {
            testcase(
                "bug: VaultWithdraw across IOU scale boundary fires invariant "
                "(pre-fixCleanup3_2_0)");
            runScenario(testableAmendments() - fixCleanup3_2_0, tecINVARIANT_FAILED);
        }
        {
            testcase(
                "bug: VaultWithdraw across IOU scale boundary succeeds "
                "(post-fixCleanup3_2_0)");
            runScenario(testableAmendments(), tesSUCCESS);
        }
    }
 
    // Bug: when a depositor's IOU trustline balance is very large (e.g.
    // ~1e17), adding a small deposit (e.g. 1 USD) leaves sfAssetsTotal
    // unchanged at IOU precision because the increment is sub-ULP at the
    // vault's current asset scale.  The vault records the deposit, mints
    // shares, and decrements the depositor's trustline, but sfAssetsTotal
    // does not change — the conservation invariant fires because the rail
    // delta is zero.
    //
    // Two sub-cases are exercised:
    //   1. First-ever deposit into an empty vault: the depositor's own
    //      trustline has a large balance so 1 USD canonicalizes to zero
    //      when written back through the IOU rail.
    //   2. Subsequent deposit after the vault already holds a large
    //      sfAssetsTotal: a different depositor (bob, with a small balance)
    //      sends 1 USD, which again rounds to zero at the vault's coarse
    //      asset scale.
    //
    // Fix (fixCleanup3_2_0): the deposit transactor checks whether
    // roundToAsset(amount, vault_scale) == 0 and rejects early with
    // tecPRECISION_LOSS before any state is modified.
    void
    testVaultDepositCanonicalizeToZero()
    {
        using namespace test::jtx;
        auto runScenario = [this](FeatureBitset features, TER expected) {
            std::string logs;
            Env env(*this, features, std::make_unique<test::CaptureLogs>(&logs));
 
            Account const issuer{"issuer"};
            Account const alice{"alice"};
            Account const bob{"bob"};
 
            env.fund(XRP(100'000), issuer, alice, bob);
            env.close();
 
            env(fset(issuer, asfDefaultRipple));
            env.close();
 
            PrettyAsset const usd{issuer["USD"]};
 
            STAmount const trustLimit{usd.raw(), Number{99'999'999'999'999'999LL}};
            STAmount const aliceFund{usd.raw(), Number{99'999'999'999'999'999LL}};
 
            env(trust(alice, trustLimit));
            env(trust(bob, trustLimit));
            env.close();
 
            env(pay(issuer, alice, aliceFund));
            env(pay(issuer, bob, usd(1000)));
            env.close();
 
            Vault const vault{env};
 
            // Scale=0 so sfAssetsTotal stores whole USD
            auto [vaultTx, vaultKeylet] = vault.create({.owner = alice, .asset = usd});
            vaultTx[sfScale] = 0;
            env(vaultTx);
            env.close();
 
            // Alice's deposit canonicalizes to zero at her own trustline scale
            env(vault.deposit({.depositor = alice, .id = vaultKeylet.key, .amount = usd(1)}),
                Ter(expected));
 
            // Increase vault-scale
            env(vault.deposit({.depositor = alice, .id = vaultKeylet.key, .amount = aliceFund}));
            env.close();
 
            env(vault.deposit({.depositor = bob, .id = vaultKeylet.key, .amount = usd(1)}),
                Ter(expected));
            env.close();
        };
 
        {
            // fixCleanup3_4_0 has to be off as well: its depositor-side check
            // rejects alice's deposit for the same reason, so the invariant is
            // only reachable with neither guard in place.
            testcase(
                "bug: VaultDeposit below Vault precision canonicalized to zero "
                "(pre-fixCleanup3_2_0)");
            // Also remove fixCleanup3_4_0 so the VaultDeposit clamp
            // introduced by that amendment does not short-circuit this
            // pre-fixCleanup3_2_0 scenario with tecPRECISION_LOSS.
            runScenario(
                testableAmendments() - fixCleanup3_2_0 - fixCleanup3_4_0, tecINVARIANT_FAILED);
        }
        {
            testcase(
                "bug: VaultDeposit below Vault precision canonicalized to zero "
                "(post-fixCleanup3_2_0)");
            runScenario(testableAmendments(), tecPRECISION_LOSS);
        }
    }
 
    // A deposit does not transfer the requested amount. It transfers the
    // request truncated to a whole number of shares and converted back, which
    // can be strictly smaller. When that smaller value is below half a ULP at
    // the depositor's own trust-line scale, the debit rounds away to nothing:
    // the depositor pays nothing, while the vault books the assets and mints
    // shares. ValidVault catches the desync at finalize time.
    //
    // Only a non-power-of-ten assets-to-shares ratio is needed, and that
    // happens through ordinary use: LoanPay books accrued interest into
    // sfAssetsTotal without minting shares.
    //
    // The fixCleanup3_2_0 guard in preclaim does not help, because it tests the
    // raw requested amount, which is large enough to survive the rounding.
    // Post-fixCleanup3_4_0 the post-truncation value is checked as well and the
    // deposit is rejected with tecPRECISION_LOSS before anything moves.
    void
    testBugDepositShareTruncationSubUlp()
    {
        using namespace test::jtx;
        using namespace loan_broker;
        using namespace loan;
 
        // How bob's trust line is set up before he deposits. Holding is the plain case: a large
        // positive balance whose ULP swallows the debit. InDebt is the case where the stored
        // balance and the spendable amount diverge: bob owes the issuer 1e16, and the issuer's
        // limit on the same line lets him spend 1000 anyway. Reading the spendable amount there
        // reports a small, finely scaled number, while the rounding of the debit is still governed
        // by the 1e16 he actually holds.
        enum class Line { Holding, InDebt };
 
        auto runScenario = [this](FeatureBitset features, Line line, TER expected) {
            std::string logs;
            Env env(*this, features, std::make_unique<test::CaptureLogs>(&logs));
 
            Account const issuer{"issuer"};
            Account const alice{"alice"};
            Account const carol{"carol"};
            Account const bob{"bob"};
 
            env.fund(XRP(100'000), issuer, alice, carol, bob);
            env.close();
            env(fset(issuer, asfDefaultRipple));
            env.close();
 
            PrettyAsset const usd{issuer["USD"]};
            PrettyAsset const bobUsd{bob["USD"]};
            STAmount const trustLimit{usd.raw(), Number{99'999'999'999'999'999LL}};
            // Bob's balance sits exactly on a multiple-of-10 boundary at the
            // 1e16 IOU precision cusp, where one ULP is 10.
            STAmount const bobEdge{usd.raw(), Number{10'000'000'000'000'010LL}};
            STAmount const bobDebt{bobUsd.raw(), Number{10'000'000'000'000'000LL}};
            STAmount const oppositeLimit{bobUsd.raw(), Number{10'000'000'000'001'000LL}};
 
            env(trust(alice, trustLimit));
            env(trust(carol, trustLimit));
            env(trust(bob, trustLimit));
            env.close();
 
            env(pay(issuer, alice, usd(1'000)));
            env(pay(issuer, carol, usd(1'000)));
            if (line == Line::Holding)
            {
                env(pay(issuer, bob, bobEdge));
            }
            else
            {
                // The issuer trusts bob's own USD, so bob can issue 1e16 back and still have
                // 1000 of spendable room left on the same line.
                env(trust(issuer, oppositeLimit));
                env.close();
                env(pay(bob, issuer, bobDebt));
            }
            env.close();
 
            Vault const vault{env};
            auto [vaultTx, vaultKeylet] = vault.create({.owner = alice, .asset = usd});
            vaultTx[sfScale] = 0;
            env(vaultTx);
            env.close();
 
            // Alice deposits 1000 USD, minting 1000 shares 1:1.
            env(vault.deposit({.depositor = alice, .id = vaultKeylet.key, .amount = usd(1'000)}));
            env.close();
 
            // A loan broker on the vault, then a bullet loan at 24% interest:
            // a single payment, one year out.
            auto const brokerKeylet =
                keylet::loanBroker(alice.id(), SeqProxy::rawSequence(env.seq(alice)));
            env(set(alice, vaultKeylet.key));
            env.close();
 
            auto const loanKeylet = keylet::loan(brokerKeylet.key, SeqProxy::rawSequence(1));
            env(set(carol, brokerKeylet.key, usd(1'000).value()),
                loan::kInterestRate(percentageToTenthBips(24)),
                kGracePeriod(60),
                kPaymentInterval(365 * 24 * 60 * 60),
                kPaymentTotal(1),
                Sig(sfCounterpartySignature, alice),
                Fee(env.current()->fees().base * 2),
                Ter(tesSUCCESS));
            env.close();
 
            // Advance to just before the single payment falls due and let carol
            // repay principal plus interest. LoanPay is what books the accrued
            // interest into sfAssetsTotal; under cash-basis accounting LoanSet
            // alone does not. Share supply stays at 1000, so
            // assetsTotal/sharesTotal becomes 1240/1000.
            env.close(std::chrono::seconds{(365 * 24 * 60 * 60) - 3600});
            env(pay(carol, loanKeylet.key, usd(2'000).value()), Ter(tesSUCCESS));
            env.close();
 
            // Pin the ratio the rest of the scenario reasons about, so the test cannot quietly
            // stop exercising the bug if the setup drifts.
            auto const sleVault = env.le(vaultKeylet);
            BEAST_EXPECT(sleVault && sleVault->at(sfAssetsTotal) == Number{1'240});
            auto const sleIssuance = env.le(keylet::mptokenIssuance(sleVault->at(sfShareMPTID)));
            BEAST_EXPECT(sleIssuance && sleIssuance->at(sfOutstandingAmount) == 1'000);
 
            // Bob deposits 6 USD, which rounds to 10 at his own trust-line
            // scale and so clears the fixCleanup3_2_0 guard. But
            // floor(1000 * 6 / 1240) is 4 shares, worth 4 * 1240 / 1000 = 4.96,
            // and that is below half a ULP of his balance, so it rounds away to
            // nothing when subtracted.
            env(vault.deposit({.depositor = bob, .id = vaultKeylet.key, .amount = usd(6)}),
                Ter(expected));
            env.close();
        };
 
        // Strip featureLendingProtocolV1_1: this scenario runs an
        // open-ended vault through deposit/broker/loan/repay/deposit,
        // which spans both Subscription and post-loan lifetime — a phase
        // pattern that only makes sense on open-ended vaults. The gate
        // added by LP V1.1 is unrelated to the truncation bug asserted
        // here.
        auto const legacy = testableAmendments() - featureLendingProtocolV1_1;
        {
            testcase(
                "bug: VaultDeposit share truncation lets depositor debit "
                "round away to zero (pre-fixCleanup3_4_0)");
            runScenario(legacy - fixCleanup3_4_0, Line::Holding, tecINVARIANT_FAILED);
        }
        {
            testcase(
                "bug: VaultDeposit share truncation lets depositor debit "
                "round away to zero (pre-fixCleanup3_2_0 and pre-fixCleanup3_4_0)");
            runScenario(
                legacy - fixCleanup3_2_0 - fixCleanup3_4_0, Line::Holding, tecINVARIANT_FAILED);
        }
        {
            testcase(
                "bug: VaultDeposit share truncation rejected with "
                "tecPRECISION_LOSS (post-fixCleanup3_4_0)");
            runScenario(legacy, Line::Holding, tecPRECISION_LOSS);
        }
        {
            testcase(
                "bug: VaultDeposit share truncation rejected with "
                "tecPRECISION_LOSS (post-fixCleanup3_4_0, pre-fixCleanup3_2_0)");
            runScenario(legacy - fixCleanup3_2_0, Line::Holding, tecPRECISION_LOSS);
        }
        {
            testcase(
                "bug: VaultDeposit share truncation against a debt balance "
                "round away to zero (pre-fixCleanup3_4_0)");
            runScenario(legacy - fixCleanup3_4_0, Line::InDebt, tecINVARIANT_FAILED);
        }
        {
            testcase(
                "bug: VaultDeposit share truncation against a debt balance rejected with "
                "tecPRECISION_LOSS (post-fixCleanup3_4_0)");
            runScenario(legacy, Line::InDebt, tecPRECISION_LOSS);
        }
    }
 
    // Bug: ValidVault::visitEntry computes destinationDelta.scale as
    // max(before_exponent, after_exponent) for RippleState entries.  When a
    // withdrawal credits a destination whose IOU balance sits just below a
    // power-of-10 boundary (atEdge = 9'999'999'999'999'999), the post-credit
    // STAmount rounds up one exponent (exponent 0 → 1), making
    // destinationDelta.scale = 1.  The invariant then calls
    // roundToAsset(+2 USD, scale=1) = 0 and incorrectly fires
    // "withdrawal must increase destination balance".
    //
    // Fix (fixCleanup3_2_0): finalize compares destination delta directly in
    // Number space, bypassing scale-coarsened rounding.  The transaction
    // itself succeeds because the effective IOU credit is non-trivial at
    // Number precision even though the STAmount exponent shifted.
    void
    testVaultWithdrawCanonicalizeToZero()
    {
        using namespace test::jtx;
 
        enum class DestKind : bool { ThirdParty = false, Self = true };
 
        auto runScenario = [this](FeatureBitset features, DestKind destKind, TER expected) {
            std::string logs;
            Env env(*this, features, std::make_unique<test::CaptureLogs>(&logs));
 
            Account const issuer{"issuer"};
            Account const alice{"alice"};
            Account const bob{"bob"};
 
            env.fund(XRP(100'000), issuer, alice, bob);
            env.close();
            env(fset(issuer, asfDefaultRipple));
            env.close();
 
            PrettyAsset const usd{issuer["USD"]};
            STAmount const aliceLimit{usd.raw(), 2, 16};
            STAmount const bobLimit{usd.raw(), 2, 16};
            STAmount const atEdge{usd.raw(), Number{9'999'999'999'999'999LL}};
 
            env(trust(alice, aliceLimit));
            if (destKind == DestKind::ThirdParty)
                env(trust(bob, bobLimit));
            env.close();
 
            env(pay(issuer, alice, usd(1'000)));
            if (destKind == DestKind::ThirdParty)
                env(pay(issuer, bob, atEdge));
            env.close();
 
            Vault const vault{env};
            auto [vaultTx, vaultKeylet] = vault.create({.owner = alice, .asset = usd});
            vaultTx[sfScale] = 0;
            env(vaultTx);
            env.close();
 
            env(vault.deposit({.depositor = alice, .id = vaultKeylet.key, .amount = usd(1'000)}));
            env.close();
 
            // For the self-destination case, push alice's own trust line to
            // the IOU edge so the next withdraw inflow crosses the boundary.
            if (destKind == DestKind::Self)
            {
                env(pay(issuer, alice, atEdge));
                env.close();
            }
 
            auto tx = vault.withdraw({.depositor = alice, .id = vaultKeylet.key, .amount = usd(2)});
            if (destKind == DestKind::ThirdParty)
                tx[sfDestination] = bob.human();
            env(tx, Ter(expected));
            env.close();
        };
 
        {
            testcase(
                "bug: VaultWithdraw to third-party at IOU edge fires invariant "
                "(pre-fixCleanup3_2_0)");
            runScenario(
                testableAmendments() - fixCleanup3_2_0, DestKind::ThirdParty, tecINVARIANT_FAILED);
        }
        {
            testcase(
                "bug: VaultWithdraw to third-party at IOU edge succeeds "
                "(post-fixCleanup3_2_0)");
            runScenario(testableAmendments(), DestKind::ThirdParty, tesSUCCESS);
        }
        {
            testcase(
                "bug: VaultWithdraw to self at IOU edge fires invariant "
                "(pre-fixCleanup3_2_0)");
            runScenario(
                testableAmendments() - fixCleanup3_2_0, DestKind::Self, tecINVARIANT_FAILED);
        }
        {
            testcase(
                "bug: VaultWithdraw to self at IOU edge succeeds "
                "(post-fixCleanup3_2_0)");
            runScenario(testableAmendments(), DestKind::Self, tesSUCCESS);
        }
    }
 
    // Bug: a debit can be genuinely non-zero yet still be dust relative to a
    // sfAssetsTotal/sfAssetsAvailable large enough to exceed STAmount's precision, e.g.
    // AssetsTotal 2e12 minus a 1e-6 debit needs 19 significant digits and rounds straight
    // back to 2e12. The shares still move, so ValidVault later fails with "must decrease
    // vault balance" instead of a clean upfront rejection.
    //
    // Fix (fixCleanup3_4_0): reject upfront with tecPRECISION_LOSS if the debit would
    // canonicalize back to the prior stored value.
    //
    // With a single depositor AssetsTotal == AssetsAvailable, so both
    // debitIsNonZeroDust operands trip together here. LoanRounding_test's
    // "dust debit vs AssetsTotal only" case isolates the AssetsTotal operand
    // via a heavily-loaned vault.
    void
    testBugVaultDustDebitCanonicalizesToNoOp()
    {
        using namespace test::jtx;
 
        // Fund a single depositor and have them deposit `total` USD in one shot (default
        // scale 6, so shares mint at exactly total*1e6).
        auto const seedVault = [](Env& env, Number const& total) {
            Account const issuer{"issuer"};
            Account const owner{"owner"};
            Account const holder{"holder"};
 
            env.fund(XRP(1'000'000), issuer, owner, holder);
            env.close();
            env(fset(issuer, asfAllowTrustLineClawback));
            env.close();
 
            PrettyAsset const usd{issuer["USD"]};
            env(trust(holder, usd(100'000'000'000'000LL)));
            env.close();
            env(pay(issuer, holder, usd(total)));
            env.close();
 
            Vault const vault{env};
            auto const [tx, keylet] = vault.create({.owner = owner, .asset = usd.raw()});
            env(tx);
            env.close();
            env(vault.deposit({.depositor = holder, .id = keylet.key, .amount = usd(total)}),
                Ter(tesSUCCESS));
            env.close();
 
            return keylet;
        };
 
        {
            auto runScenario = [&](FeatureBitset features, TER expected) {
                Env env(*this, features);
                Number const total{2, 12};
                auto const keylet = seedVault(env, total);
 
                Account const issuer{"issuer"};
                PrettyAsset const usd{issuer["USD"]};
 
                // 1 share's worth of assets: 1e-6, below AssetsTotal's storage precision.
                env(Vault::clawback(
                        {.issuer = issuer,
                         .id = keylet.key,
                         .holder = Account{"holder"},
                         .amount = usd(Number{1, -6}).value()}),
                    Ter(expected));
                env.close();
            };
 
            testcase("bug: VaultClawback dust debit fires invariant (pre-fixCleanup3_4_0)");
            runScenario(all_ - fixCleanup3_4_0, tecINVARIANT_FAILED);
            testcase("bug: VaultClawback dust debit rejected cleanly (post-fixCleanup3_4_0)");
            runScenario(all_, tecPRECISION_LOSS);
        }
 
        {
            auto runScenario = [&](FeatureBitset features, TER expected) {
                Env env(*this, features);
                Number const total{2, 12};
                auto const keylet = seedVault(env, total);
 
                MPTIssue const share{env.le(keylet)->at(sfShareMPTID)};
 
                // Redeem 1 share, worth 1e-6 assets, below AssetsTotal's storage precision.
                env(Vault::withdraw(
                        {.depositor = Account{"holder"},
                         .id = keylet.key,
                         .amount = STAmount{share, 1}}),
                    Ter(expected));
                env.close();
            };
 
            testcase("bug: VaultWithdraw dust debit fires invariant (pre-fixCleanup3_4_0)");
            runScenario(all_ - fixCleanup3_4_0, tecINVARIANT_FAILED);
            testcase("bug: VaultWithdraw dust debit rejected cleanly (post-fixCleanup3_4_0)");
            runScenario(all_, tecPRECISION_LOSS);
        }
    }
 
    // Scale 15 seed + deposit 5: pre-fix credited > paid; post-fix credited <= paid.
    // fixCleanup3_2_0 is off so roundToVaultScale does not shrink the deposit first.
    void
    testBugVaultDepositOvercreditsAcrossScaleBoundary()
    {
        using namespace test::jtx;
 
        auto runScenario = [this](FeatureBitset features, bool expectOvercredit) {
            Env env(*this, features);
            Account const owner{"owner"};
            Account const issuer{"issuer"};
            Account const depositor{"depositor"};
            env.fund(XRP(1'000'000), owner, issuer, depositor);
            env.close();
 
            PrettyAsset const usd{issuer["USD"]};
            Number const seed{9'999'999'999'999'999LL, -15};
            Number const deposit{5};
 
            env(trust(depositor, usd(1'000'000'000)));
            env.close();
            env(pay(issuer, depositor, usd(deposit)));
            env.close();
 
            Vault const vault{env};
            auto [tx, keylet] = vault.create({.owner = owner, .asset = usd.raw()});
            tx[sfScale] = 15;
            env(tx);
            env.close();
            env(vault.deposit({.depositor = issuer, .id = keylet.key, .amount = usd(seed)}));
            env.close();
 
            Number const totalBefore = env.le(keylet)->at(sfAssetsTotal);
            Number const depositorBefore = env.balance(depositor, usd.raw()).number();
 
            env(vault.deposit({.depositor = depositor, .id = keylet.key, .amount = usd(deposit)}));
            env.close();
 
            Number const totalAfter = env.le(keylet)->at(sfAssetsTotal);
            Number const depositorAfter = env.balance(depositor, usd.raw()).number();
            Number const paid = depositorBefore - depositorAfter;
            Number const credited = totalAfter - totalBefore;
 
            if (expectOvercredit)
            {
                BEAST_EXPECTS(
                    credited > paid,
                    "AssetsTotal credited " + to_string(credited) + " for a payment of " +
                        to_string(paid) + ", expected an overcredit");
            }
            else
            {
                BEAST_EXPECTS(
                    credited <= paid,
                    "AssetsTotal credited " + to_string(credited) + " for a payment of " +
                        to_string(paid));
            }
        };
 
        testcase(
            "bug: VaultDeposit overcredits across an IOU scale boundary "
            "(pre-fixCleanup3_4_0)");
        runScenario(all_ - fixCleanup3_2_0 - fixCleanup3_4_0, true);
 
        testcase(
            "bug: VaultDeposit no longer overcredits across an IOU scale boundary "
            "(post-fixCleanup3_4_0)");
        runScenario(all_, false);
    }
 
    // 1e17 IOU at scale 0. Withdraw all-but-one, then the last share:
    // pre-fix tecINVARIANT_FAILED, post-fix tesSUCCESS.
    void
    testBugVaultLockedByPartialWithdraw()
    {
        using namespace test::jtx;
 
        auto runScenario = [this](FeatureBitset features, TER expected) {
            Env env(*this, features);
            Account const owner{"owner"};
            Account const issuer{"issuer"};
            Account const holder{"holder"};
            env.fund(XRP(1'000'000), owner, issuer, holder);
            env.close();
 
            PrettyAsset const usd{issuer["USD"]};
            env(trust(holder, usd(Number{1, 18})));
            env.close();
            env(pay(issuer, holder, usd(Number{1, 17})));
            env.close();
 
            Vault const vault{env};
            auto [tx, keylet] = vault.create({.owner = owner, .asset = usd.raw()});
            tx[sfScale] = 0;
            env(tx);
            env.close();
            env(vault.deposit(
                {.depositor = holder, .id = keylet.key, .amount = usd(Number{1, 17})}));
            env.close();
 
            MPTIssue const share{env.le(keylet)->at(sfShareMPTID)};
            std::int64_t const allButOne = 100'000'000'000'000'000LL - 1;
            env(vault.withdraw(
                {.depositor = holder, .id = keylet.key, .amount = STAmount{share, allButOne}}));
            env.close();
 
            env(vault.withdraw(
                    {.depositor = holder, .id = keylet.key, .amount = STAmount{share, 1}}),
                Ter(expected));
            env.close();
        };
 
        testcase(
            "bug: VaultWithdraw permanently locks a large IOU vault "
            "(pre-fixCleanup3_4_0)");
        runScenario(all_ - fixCleanup3_4_0, tecINVARIANT_FAILED);
        testcase(
            "bug: VaultWithdraw no longer locks a large IOU vault "
            "(post-fixCleanup3_4_0)");
        runScenario(all_, tesSUCCESS);
    }
 
    // VaultDeposit::preclaim uses accountHolds(..., SpendableHandling::
    // shFULL_BALANCE), which for an IOU asset adds the counterparty's
    // LowLimit/HighLimit to the depositor's raw balance (TokenHelpers.cpp:
    // getTrustLineBalance with includeOppositeLimit=true). When the
    // depositor's raw balance < deposit amount but raw + opposite limit >=
    // amount, preclaim is satisfied. doApply then calls
    // directSendNoFeeIOU, which unconditionally subtracts saAmount from
    // saBalance — driving the trust line negative — and returns tesSUCCESS.
    // The post-send sanity check uses the default shSIMPLE_BALANCE (no
    // opposite-limit add), sees a negative balance, and returns tefINTERNAL.
    void
    testVaultDepositNegativeBalanceFromOppositeLimit()
    {
        auto runTest = [&](FeatureBitset f, TER expected) {
            using namespace test::jtx;
            using namespace std::literals;
 
            Env env{*this, f};
            Account const gw{"gateway"};
            Account const owner{"owner"};
            Account const depositor{"depositor"};
 
            env.fund(XRP(10000), gw, owner, depositor);
            env.close();
 
            // Gateway with DefaultRipple so vault creation on its IOU works.
            env(fset(gw, asfDefaultRipple));
            env.close();
 
            // Depositor opens a trust line to gateway and receives a small
            // balance.
            PrettyAsset const usd = gw["USD"];
            env.trust(usd(1000), depositor);
            env(pay(gw, depositor, usd(100)));  // raw trust-line balance: 100
            env.close();
 
            // Key precondition: gateway sets a non-zero limit on the same
            // RippleState — the "opposite field" from depositor's perspective.
            // This is what inflates shFULL_BALANCE in preclaim above the raw
            // balance.
            env(trust(gw, depositor["USD"](1000)));
            env.close();
 
            // Create the IOU vault.
            Vault const vault{env};
            auto [vaultTx, keylet] = vault.create({.owner = owner, .asset = usd});
            env(vaultTx);
            env.close();
 
            // Submit a deposit of 500 USD:
            //   - raw balance:                100 USD
            //   - opposite limit (gw's side): 1000 USD
            //   - preclaim sees 100 + 1000 = 1100, passes (>= 500)
            //   - doApply transfers 500, depositor's trust-line balance
            //     becomes -400
            //   - sanity check at VaultDeposit.cpp:256 fires
            //   - tx returns tefINTERNAL (BUG — should be tesSUCCESS.
            auto depositTx =
                vault.deposit({.depositor = depositor, .id = keylet.key, .amount = usd(500)});
            env(depositTx, Ter(expected));
            env.close();
        };
 
        {
            testcase(
                "IOU vault deposit exceeding depositor's balance but "
                "within counterparty's trust limit, pre-fixCleanup3_2_0 "
                "(tefINTERNAL)");
            runTest(test::jtx::testableAmendments() - fixCleanup3_2_0, tefINTERNAL);
        }
        {
            testcase(
                "IOU vault deposit exceeding depositor's balance but "
                "within counterparty's trust limit, post-fixCleanup3_2_0 "
                "(tesSUCCESS)");
            runTest(test::jtx::testableAmendments(), tesSUCCESS);
        }
    }
 
    // Reproduction: canWithdraw IOU limit check bypassed when
    // withdrawal amount is specified in shares (MPT) rather than in assets.
    void
    testBug6LimitBypassWithShares()
    {
        using namespace test::jtx;
        testcase("Bug6 - limit bypass with share-denominated withdrawal");
 
        auto const allAmendments = testableAmendments() | featureSingleAssetVault;
 
        for (auto const& features : {allAmendments, allAmendments - fixCleanup3_1_3})
        {
            bool const withFix = features[fixCleanup3_1_3];
 
            Env env{*this, features};
            Account const owner{"owner"};
            Account const issuer{"issuer"};
            Account const depositor{"depositor"};
            Account const charlie{"charlie"};
            Vault const vault{env};
 
            env.fund(XRP(1000), issuer, owner, depositor, charlie);
            env(fset(issuer, asfAllowTrustLineClawback));
            env.close();
 
            PrettyAsset const asset = issuer["IOU"];
            env.trust(asset(1000), owner);
            env.trust(asset(1000), depositor);
            env(pay(issuer, owner, asset(200)));
            env(pay(issuer, depositor, asset(200)));
            env.close();
 
            // Charlie gets a LOW trustline limit of 5
            env.trust(asset(5), charlie);
            env.close();
 
            auto const [tx, keylet] = vault.create({.owner = owner, .asset = asset});
            env(tx);
            env.close();
 
            auto const depositTx =
                vault.deposit({.depositor = depositor, .id = keylet.key, .amount = asset(100)});
            env(depositTx);
            env.close();
 
            // Get the share MPT info
            auto const vaultSle = env.le(keylet);
            if (!BEAST_EXPECT(vaultSle))
                return;
            auto const mptIssuanceID = vaultSle->at(sfShareMPTID);
            MPTIssue const shares(mptIssuanceID);
            PrettyAsset const share(shares);
 
            // CONTROL: Withdraw 10 IOU (asset-denominated) to charlie.
            // Charlie's limit is 5, so this should be rejected with tecNO_LINE
            // regardless of the amendment.
            {
                auto withdrawTx =
                    vault.withdraw({.depositor = depositor, .id = keylet.key, .amount = asset(10)});
                withdrawTx[sfDestination] = charlie.human();
                env(withdrawTx, Ter{tecNO_LINE});
                env.close();
            }
            auto const charlieBalanceBefore = env.balance(charlie, asset.raw().get<Issue>());
 
            // Withdraw the equivalent amount in shares to charlie.
            // Post-fix: rejected (tecNO_LINE) because the share amount is
            //   converted to assets and the trustline limit is checked.
            // Pre-fix: succeeds (tesSUCCESS) because the limit check was
            //   skipped for share-denominated withdrawals.
            {
                auto withdrawTx = vault.withdraw(
                    {.depositor = depositor,
                     .id = keylet.key,
                     .amount = STAmount(share, 10'000'000)});
                withdrawTx[sfDestination] = charlie.human();
                env(withdrawTx, Ter{withFix ? TER{tecNO_LINE} : TER{tesSUCCESS}});
                env.close();
 
                auto const charlieBalanceAfter = env.balance(charlie, asset.raw().get<Issue>());
                if (withFix)
                {
                    // Post-fix: charlie's balance is unchanged — the withdrawal
                    // was correctly rejected despite being share-denominated.
                    BEAST_EXPECT(charlieBalanceAfter == charlieBalanceBefore);
                }
                else
                {
                    // Pre-fix: charlie received the assets, bypassing the
                    // trustline limit.
                    BEAST_EXPECT(charlieBalanceAfter > charlieBalanceBefore);
                }
            }
        }
    }
 
    // Shared setup for testBugClawbackRoundTripOvershoot and
    // testBugWithdrawRoundTripOvershoot, which both need a vault at
    // assetsTotal=7, sharesTotal=5 and differ only in what they do once
    // that state is reached.
    //
    // The (7, 5) state is reached through ordinary transactions: a 5 USD
    // deposit mints 5 shares 1:1, then a loan broker on the vault issues a
    // single-payment bullet loan for the full 5 USD at 40% interest. When
    // the borrower repays a year later, LoanPay books the 2 USD of accrued
    // interest into sfAssetsTotal without minting shares, leaving
    // assetsTotal=7 against sharesTotal=5 (see
    // testBugDepositShareTruncationSubUlp for the same technique in more
    // detail).
    struct RoundTripOvershootVault
    {
        test::jtx::Account issuer;
        test::jtx::Account holder;
        PrettyAsset usd;
        test::jtx::Vault vault;
        Keylet vaultKeylet;
        Number initialAssetsTotal;
        Number initialAssetsAvailable;
    };
 
    std::optional<RoundTripOvershootVault>
    makeRoundTripOvershootVault(test::jtx::Env& env)
    {
        using namespace test::jtx;
        using namespace loan_broker;
        using namespace loan;
 
        Account const issuer{"issuer"};
        Account const owner{"owner"};
        Account const holder{"holder"};
        Account const borrower{"borrower"};
 
        env.fund(XRP(10'000), issuer, owner, holder, borrower);
        env.close();
 
        env(fset(issuer, asfAllowTrustLineClawback));
        env.close();
 
        PrettyAsset const usd = issuer["USD"];
        env.trust(usd(1'000), owner);
        env.trust(usd(1'000), holder);
        env.trust(usd(1'000), borrower);
        env.close();
 
        env(pay(issuer, holder, usd(100)));
        env(pay(issuer, borrower, usd(100)));
        env.close();
 
        Vault const vault{env};
        auto [vaultTx, vaultKeylet] = vault.create({.owner = owner, .asset = usd});
        vaultTx[sfScale] = 0;
        env(vaultTx);
        env.close();
 
        // Holder deposits 5 USD, minting 5 shares 1:1.
        env(vault.deposit({.depositor = holder, .id = vaultKeylet.key, .amount = usd(5)}));
        env.close();
 
        // A loan broker on the vault, then a single bullet loan for the
        // entire deposit at 40% interest, one payment, one year out.
        auto const brokerKeylet =
            keylet::loanBroker(owner.id(), SeqProxy::rawSequence(env.seq(owner)));
        env(set(owner, vaultKeylet.key));
        env.close();
 
        auto const loanKeylet = keylet::loan(brokerKeylet.key, SeqProxy::rawSequence(1));
        env(set(borrower, brokerKeylet.key, usd(5).value()),
            loan::kInterestRate(percentageToTenthBips(40)),
            kGracePeriod(60),
            kPaymentInterval(365 * 24 * 60 * 60),
            kPaymentTotal(1),
            Sig(sfCounterpartySignature, owner),
            Fee(env.current()->fees().base * 2),
            Ter(tesSUCCESS));
        env.close();
 
        // Advance to just before the single payment falls due and let the
        // borrower repay principal plus interest. Share supply stays at 5,
        // so assetsTotal/sharesTotal becomes 7/5.
        env.close(std::chrono::seconds{(365 * 24 * 60 * 60) - 3600});
        env(pay(borrower, loanKeylet.key, usd(10).value()), Ter(tesSUCCESS));
        env.close();
 
        auto const vaultSle = env.le(vaultKeylet);
        if (!BEAST_EXPECT(vaultSle))
            return std::nullopt;
        auto const mptIssuanceID = vaultSle->at(sfShareMPTID);
 
        Number const initialAssetsTotal = vaultSle->at(sfAssetsTotal);
        Number const initialAssetsAvailable = vaultSle->at(sfAssetsAvailable);
        BEAST_EXPECT(initialAssetsTotal == usd(7).number());
        BEAST_EXPECT(initialAssetsAvailable == usd(7).number());
        {
            auto const sleIssuance = env.le(keylet::mptokenIssuance(mptIssuanceID));
            if (!BEAST_EXPECT(sleIssuance))
                return std::nullopt;
            BEAST_EXPECT(sleIssuance->getFieldU64(sfOutstandingAmount) == 5);
        }
 
        return RoundTripOvershootVault{
            .issuer = issuer,
            .holder = holder,
            .usd = usd,
            .vault = vault,
            .vaultKeylet = vaultKeylet,
            .initialAssetsTotal = initialAssetsTotal,
            .initialAssetsAvailable = initialAssetsAvailable};
    }
 
    // VaultClawback::assetsToClawback converts clawbackAmount to shares
    // with round-to-nearest, then round-trips back to assets. When shares
    // round up, assetsRecovered can exceed clawbackAmount.
    //
    // Repro: assetsTotal=7, sharesTotal=5, request 4:
    //   shares = round(20/7) = 3, assets = 7*3/5 = 4.2 > 4.
    //
    // Post-fixCleanup3_4_0: truncate shares so assetsRecovered <=
    // clawbackAmount by construction.
    void
    testBugClawbackRoundTripOvershoot()
    {
        using namespace test::jtx;
 
        auto runScenario = [this](FeatureBitset features, bool withFix) {
            // This regression requires the open-ended vault lifecycle: deposit,
            // originate and repay a loan, then claw back shares. LP V1.1
            // independently rejects attaching a broker to an open-ended vault.
            Env env{*this, features - featureLendingProtocolV1_1};
 
            auto const setup = makeRoundTripOvershootVault(env);
            if (!BEAST_EXPECT(setup))
                return;
 
            auto const clawbackAmount = setup->usd(4);
            env(setup->vault.clawback(
                {.issuer = setup->issuer,
                 .id = setup->vaultKeylet.key,
                 .holder = setup->holder,
                 .amount = clawbackAmount.value()}));
 
            auto const vaultSleAfter = env.current()->read(setup->vaultKeylet);
            if (!BEAST_EXPECT(vaultSleAfter))
                return;
            Number const finalAssetsTotal = vaultSleAfter->at(sfAssetsTotal);
            Number const assetsRecovered = setup->initialAssetsTotal - finalAssetsTotal;
            Number const clawbackNum = clawbackAmount.number();
 
            Number const expectedPost{28LL, -1};
            Number const expectedPre{42LL, -1};
            if (withFix)
            {
                BEAST_EXPECT(assetsRecovered <= clawbackNum);
                BEAST_EXPECT(assetsRecovered == expectedPost);
            }
            else
            {
                BEAST_EXPECT(assetsRecovered > clawbackNum);
                BEAST_EXPECT(assetsRecovered == expectedPre);
            }
        };
 
        {
            testcase(
                "bug: VaultClawback round-trip overshoot lets issuer recover "
                "more than requested (pre-fixCleanup3_4_0)");
            runScenario(testableAmendments() - fixCleanup3_4_0, false);
        }
        {
            testcase(
                "bug: VaultClawback round-trip overshoot is clamped so "
                "assetsRecovered <= clawbackAmount (post-fixCleanup3_4_0)");
            runScenario(testableAmendments(), true);
        }
    }
 
    // Same root cause as testBugClawbackRoundTripOvershoot on the
    // withdraw path. Also bypasses the preclaim canWithdraw check, which
    // validates destination limits against the requested amount only.
    //
    // Repro: assetsTotal=7, sharesTotal=5, request 4:
    //   pre-fix : shares = round(20/7) = 3, assets = 7*3/5 = 4.2 > 4.
    //   post-fix: shares = floor(20/7) = 2, assets = 7*2/5 = 2.8 <= 4.
    void
    testBugWithdrawRoundTripOvershoot()
    {
        using namespace test::jtx;
 
        auto runScenario = [this](FeatureBitset features, bool withFix) {
            // This regression requires the open-ended vault lifecycle: deposit,
            // originate and repay a loan, then withdraw shares. LP V1.1
            // independently rejects attaching a broker to an open-ended vault.
            Env env{*this, features - featureLendingProtocolV1_1};
 
            auto const setup = makeRoundTripOvershootVault(env);
            if (!BEAST_EXPECT(setup))
                return;
 
            auto const requested = setup->usd(4);
            env(setup->vault.withdraw(
                {.depositor = setup->holder,
                 .id = setup->vaultKeylet.key,
                 .amount = requested.value()}));
 
            auto const vaultSleAfter = env.current()->read(setup->vaultKeylet);
            if (!BEAST_EXPECT(vaultSleAfter))
                return;
            Number const finalAssetsTotal = vaultSleAfter->at(sfAssetsTotal);
            Number const assetsWithdrawn = setup->initialAssetsTotal - finalAssetsTotal;
            Number const requestedNum = requested.number();
 
            Number const expectedPost{28LL, -1};
            Number const expectedPre{42LL, -1};
            if (withFix)
            {
                BEAST_EXPECT(assetsWithdrawn <= requestedNum);
                BEAST_EXPECT(assetsWithdrawn == expectedPost);
            }
            else
            {
                BEAST_EXPECT(assetsWithdrawn > requestedNum);
                BEAST_EXPECT(assetsWithdrawn == expectedPre);
            }
        };
 
        {
            testcase(
                "bug: VaultWithdraw round-trip overshoot delivers more than "
                "requested (pre-fixCleanup3_4_0)");
            runScenario(testableAmendments() - fixCleanup3_4_0, false);
        }
        {
            testcase(
                "bug: VaultWithdraw round-trip overshoot is clamped so "
                "assetsWithdrawn <= requested (post-fixCleanup3_4_0)");
            runScenario(testableAmendments(), true);
        }
    }
 
    struct ImpairedLoanVault
    {
        test::jtx::Account issuer;
        test::jtx::Account holder;
        PrettyAsset usd;
        test::jtx::Vault vault;
        Keylet vaultKeylet;
        MPTID shareId;
    };
 
    // Impairing a 1,000 loan in a 10,000 vault leaves AssetsAvailable=9,000
    // and AssetsTotal=10,000. otherDeposit > 0 splits the shares, 0 leaves
    // holder as the sole shareholder.
    std::optional<ImpairedLoanVault>
    makeImpairedLoanVault(test::jtx::Env& env, int otherDeposit)
    {
        using namespace test::jtx;
        using namespace loan_broker;
        using namespace loan;
 
        Account const issuer{"issuer"};
        Account const owner{"owner"};
        Account const holder{"holder"};
        Account const other{"other"};
        Account const borrower{"borrower"};
 
        env.fund(XRP(100'000), issuer, owner, holder, other, borrower);
        env.close();
 
        env(fset(issuer, asfAllowTrustLineClawback));
        env(fset(issuer, asfDefaultRipple));
        env.close();
 
        PrettyAsset const usd = issuer["USD"];
        env.trust(usd(100'000), owner);
        env.trust(usd(100'000), holder);
        env.trust(usd(100'000), other);
        env.trust(usd(100'000), borrower);
        env.close();
 
        int const holderDeposit = 10'000 - otherDeposit;
        env(pay(issuer, holder, usd(holderDeposit)));
        if (otherDeposit != 0)
        {
            env(pay(issuer, other, usd(otherDeposit)));
        }
        env.close();
 
        Vault const vault{env};
        auto const [createTx, vaultKeylet, subscriptionDate] = vault.createClosedEnded(
            {.owner = owner, .asset = usd, .subscriptionOffset = std::chrono::seconds{60}});
        env(createTx);
        env.close();
 
        auto const vaultSle = env.le(vaultKeylet);
        if (!BEAST_EXPECT(vaultSle))
            return std::nullopt;
        MPTID const shareId = vaultSle->at(sfShareMPTID);
 
        env(vault.deposit(
            {.depositor = holder, .id = vaultKeylet.key, .amount = usd(holderDeposit)}));
        if (otherDeposit != 0)
        {
            env(vault.deposit(
                {.depositor = other, .id = vaultKeylet.key, .amount = usd(otherDeposit)}));
        }
        env.close();
 
        vault.closePastSubscription(subscriptionDate);
 
        auto const brokerKeylet =
            keylet::loanBroker(owner.id(), SeqProxy::rawSequence(env.seq(owner)));
        env(set(owner, vaultKeylet.key));
        env.close();
 
        auto const sleBroker = env.le(brokerKeylet);
        if (!BEAST_EXPECT(sleBroker))
            return std::nullopt;
        auto const loanKeylet =
            keylet::loan(brokerKeylet.key, SeqProxy::rawSequence(sleBroker->at(sfLoanSequence)));
 
        env(set(borrower, brokerKeylet.key, usd(1'000).value()),
            loan::kInterestRate(percentageToTenthBips(0)),
            kGracePeriod(60),
            kPaymentInterval(120),
            kPaymentTotal(10),
            Sig(sfCounterpartySignature, owner),
            Fee(env.current()->fees().base * 2),
            Ter(tesSUCCESS));
        env.close();
 
        // Under fixCleanup3_4_0, LoanManage rejects tfLoanImpair with
        // tecTOO_SOON unless the payment is already late; advance the ledger
        // past sfNextPaymentDueDate so impairment succeeds. No-op otherwise.
        if (env.current()->rules().enabled(fixCleanup3_4_0))
        {
            auto const loanBefore = env.le(loanKeylet);
            if (!BEAST_EXPECT(loanBefore))
                return std::nullopt;
            std::uint32_t const dueDate = loanBefore->at(sfNextPaymentDueDate);
            env.close(NetClock::time_point{NetClock::duration{dueDate}} + std::chrono::seconds{1});
        }
 
        env(manage(owner, loanKeylet.key, tfLoanImpair), Ter(tesSUCCESS));
        env.close();
 
        auto const vaultAfter = env.le(vaultKeylet);
        if (!BEAST_EXPECT(vaultAfter))
            return std::nullopt;
        BEAST_EXPECT(vaultAfter->at(sfAssetsAvailable) == usd(9'000).value());
        BEAST_EXPECT(vaultAfter->at(sfLossUnrealized) == usd(1'000).value());
 
        return ImpairedLoanVault{
            .issuer = issuer,
            .holder = holder,
            .usd = usd,
            .vault = vault,
            .vaultKeylet = vaultKeylet,
            .shareId = shareId};
    }
 
    // Legacy clawback pricing burns every share; fixCleanup3_4_0 leaves 10%
    // outstanding, backed by the impaired receivable.
    void
    testBugClawbackAfterLoanImpair()
    {
        using namespace test::jtx;
 
        auto clawbackHolder = [](ImpairedLoanVault const& setup, STAmount const& amount) {
            return setup.vault.clawback(
                {.issuer = setup.issuer,
                 .id = setup.vaultKeylet.key,
                 .holder = setup.holder,
                 .amount = amount});
        };
 
        auto runSole = [this, &clawbackHolder](FeatureBitset features, TER expected) {
            testcase(
                features[fixCleanup3_4_0]
                    ? "VaultClawback after impaired loan (post-fixCleanup3_4_0)"
                    : "VaultClawback after impaired loan (pre-fixCleanup3_4_0)");
 
            Env env(*this, features);
            auto const maybeSetup = makeImpairedLoanVault(env, 0);
            if (!maybeSetup)
            {
                BEAST_EXPECT(false);
                return;
            }
            ImpairedLoanVault const& setup = *maybeSetup;
 
            auto const tokenBefore = env.le(keylet::mptoken(setup.shareId, setup.holder.id()));
            auto const vaultBefore = env.le(setup.vaultKeylet);
            auto const issuanceBefore = env.le(keylet::mptokenIssuance(setup.shareId));
            if (!BEAST_EXPECT(tokenBefore) || !BEAST_EXPECT(vaultBefore) ||
                !BEAST_EXPECT(issuanceBefore))
                return;
            std::uint64_t const sharesBefore = tokenBefore->getFieldU64(sfMPTAmount);
 
            // The clawback of 19,000 exceeds AssetsAvailable (9,000), so
            // VaultClawback clamps sharesDestroyed to whatever redeems
            // exactly AssetsAvailable; compute that expected value using the
            // same conversion helper VaultClawback itself uses, rather than
            // assuming an exact 90/10 split holds under truncation.
            auto const maybeSharesDestroyed = assetsToSharesWithdraw(
                vaultBefore,
                issuanceBefore,
                setup.usd(9'000).value(),
                TruncateShares::Yes,
                WaiveUnrealizedLoss::Yes);
            if (!BEAST_EXPECT(maybeSharesDestroyed))
                return;
            std::uint64_t const expectedSharesAfter =
                sharesBefore - maybeSharesDestroyed->mpt().value();
 
            env(clawbackHolder(setup, setup.usd(19'000).value()), Ter(expected));
            env.close();
            if (expected != tesSUCCESS)
                return;
 
            auto const vaultAfter = env.le(setup.vaultKeylet);
            if (!BEAST_EXPECT(vaultAfter))
                return;
            BEAST_EXPECT(vaultAfter->at(sfAssetsAvailable) == setup.usd(0).value());
            BEAST_EXPECT(vaultAfter->at(sfAssetsTotal) == setup.usd(1'000).value());
            BEAST_EXPECT(vaultAfter->at(sfLossUnrealized) == setup.usd(1'000).value());
            auto const tokenAfter = env.le(keylet::mptoken(setup.shareId, setup.holder.id()));
            if (!BEAST_EXPECT(tokenAfter))
                return;
            BEAST_EXPECT(tokenAfter->getFieldU64(sfMPTAmount) == expectedSharesAfter);
        };
 
        runSole(all_ - fixCleanup3_4_0, tecINVARIANT_FAILED);
        runSole(all_, tesSUCCESS);
 
        testcase("VaultClawback after impaired loan, non-sole holder");
        {
            Env env(*this, all_);
            auto const maybeSetup = makeImpairedLoanVault(env, 1'000);
            if (!maybeSetup)
            {
                BEAST_EXPECT(false);
                return;
            }
            ImpairedLoanVault const& setup = *maybeSetup;
            // The waiver does not apply, so the holder's 9,000 shares are
            // still priced at the discounted rate and cannot cover 9,000.
            env(clawbackHolder(setup, setup.usd(9'000).value()), Ter(tecINSUFFICIENT_FUNDS));
        }
    }
 
    // Bug: a fully impaired vault may pay zero assets for a share burn.
    // Sending zero MPT is a no-op, so the vault pseudo-account's asset
    // MPToken is never written and ValidVault, which only records deltas for
    // created, modified or deleted entries, sees no vault delta at all.
    //
    // Pre-fixCleanup3_4_0 that alone makes the withdrawal impossible:
    // zeroDeltaIsLegitimate is gated on the amendment, so the absent vault
    // delta fails "withdrawal must change vault balance". Every pre-amendment
    // arm below dies there, before any destination-side check runs.
    //
    // The destination side differs per arm, and only the vault-delta return
    // hides that pre-amendment. With Alice's asset MPToken already present
    // nothing touches it, so she has no delta either. With it missing,
    // doWithdraw still called addEmptyHolding for a self-destination on a
    // zero payout and created her MPToken at amount 0; a created MPToken is
    // recorded even at zero, so she arrives with a present-and-zero delta,
    // which for an integral MPT asset the destination check would reject if
    // it were reached.
    //
    // ValidMPTIssuance: pre-fixCleanup3_4_0, a VaultWithdraw that both
    // creates and deletes an MPToken fails. Post-fixCleanup3_4_0 that is
    // allowed.
 
    //
    // Post-fixCleanup3_4_0, doWithdraw skips addEmptyHolding on a zero
    // payout and zeroDeltaIsLegitimate lets the vault-delta and
    // missing-recipient-delta checks accept the transfer. A present
    // destination delta of zero is still rejected.
    void
    testBugMptZeroWithdrawMissingHolding()
    {
        using namespace test::jtx;
        using namespace loan_broker;
        using namespace loan;
        using namespace std::chrono_literals;
 
        auto runScenario = [this](
                               FeatureBitset features,
                               bool removeAssetToken,
                               bool withdrawAllAliceShares,
                               TER expected) {
            testcase(
                std::string{"bug: MPT vault zero-value withdraw "} +
                (removeAssetToken ? "without asset MPToken" : "with asset MPToken") +
                (withdrawAllAliceShares ? ", Alice's last share" : ", Alice has leftover shares") +
                (features[fixCleanup3_4_0] ? " (post-fixCleanup3_4_0)" : " (pre-fixCleanup3_4_0)"));
 
            Env env(*this, features);
 
            Account const issuer{"issuer"};
            Account const owner{"owner"};
            Account const alice{"alice"};
            Account const bob{"bob"};
            Account const borrower{"borrower"};
 
            env.fund(XRP(100'000), issuer, owner, alice, bob, borrower);
            env.close();
 
            MPTTester mptt{env, issuer, kMptInitNoFund};
            mptt.create({.flags = tfMPTCanTransfer});
            PrettyAsset const asset = mptt.issuanceID();
            mptt.authorize({.account = owner});
            mptt.authorize({.account = alice});
            mptt.authorize({.account = bob});
            mptt.authorize({.account = borrower});
            env.close();
 
            env(pay(issuer, alice, asset(2)));
            env(pay(issuer, bob, asset(8)));
            env.close();
 
            Vault const vault{env};
            auto const [createTx, vaultKeylet, subscriptionDate] = vault.createClosedEnded(
                {.owner = owner, .asset = asset, .subscriptionOffset = 60s});
            env(createTx);
            env.close();
 
            env(vault.deposit({.depositor = alice, .id = vaultKeylet.key, .amount = asset(2)}));
            env(vault.deposit({.depositor = bob, .id = vaultKeylet.key, .amount = asset(8)}));
            env.close();
 
            vault.closePastSubscription(subscriptionDate);
 
            auto const brokerKeylet =
                keylet::loanBroker(owner.id(), SeqProxy::rawSequence(env.seq(owner)));
            env(set(owner, vaultKeylet.key));
            env.close();
 
            auto const sleBroker = env.le(brokerKeylet);
            if (!BEAST_EXPECT(sleBroker))
                return;
            auto const loanKeylet = keylet::loan(
                brokerKeylet.key, SeqProxy::rawSequence(sleBroker->at(sfLoanSequence)));
 
            env(set(borrower, brokerKeylet.key, asset(10).value()),
                kInterestRate(percentageToTenthBips(0)),
                kGracePeriod(60),
                kPaymentInterval(120),
                kPaymentTotal(10),
                Sig(sfCounterpartySignature, owner),
                Fee(env.current()->fees().base * 2),
                Ter(tesSUCCESS));
            env.close();
 
            auto const loanBefore = env.le(loanKeylet);
            if (!BEAST_EXPECT(loanBefore))
                return;
            std::uint32_t const dueDate = loanBefore->at(sfNextPaymentDueDate);
            env.close(NetClock::time_point{NetClock::duration{dueDate}} + 1s);
 
            env(manage(owner, loanKeylet.key, tfLoanImpair), Ter(tesSUCCESS));
            env.close();
 
            auto const vaultImpaired = env.le(vaultKeylet);
            if (!BEAST_EXPECT(vaultImpaired))
                return;
            BEAST_EXPECT(vaultImpaired->at(sfAssetsAvailable) == asset(0).value());
            BEAST_EXPECT(vaultImpaired->at(sfAssetsTotal) == vaultImpaired->at(sfLossUnrealized));
            Number const totalBefore = vaultImpaired->at(sfAssetsTotal);
            Number const lossBefore = vaultImpaired->at(sfLossUnrealized);
 
            MPTID const shareId = vaultImpaired->at(sfShareMPTID);
            auto const issuanceBefore = env.le(keylet::mptokenIssuance(shareId));
            if (!BEAST_EXPECT(issuanceBefore))
                return;
            std::uint64_t const outstandingBefore =
                issuanceBefore->getFieldU64(sfOutstandingAmount);
 
            auto const tokenAlice = env.le(keylet::mptoken(shareId, alice.id()));
            if (!BEAST_EXPECT(tokenAlice))
                return;
            std::uint64_t const sharesBefore = tokenAlice->getFieldU64(sfMPTAmount);
            BEAST_EXPECT(sharesBefore == 2);
            std::uint64_t const sharesToRedeem = withdrawAllAliceShares ? sharesBefore : 1;
            STAmount const redeemShares{MPTIssue{shareId}, Number(sharesToRedeem)};
 
            auto const assetTokenKeylet = keylet::mptoken(mptt.issuanceID(), alice.id());
            if (removeAssetToken)
            {
                mptt.authorize({.account = alice, .flags = tfMPTUnauthorize});
                env.close();
                BEAST_EXPECT(!env.le(assetTokenKeylet));
            }
            else
            {
                auto const existing = env.le(assetTokenKeylet);
                if (!BEAST_EXPECT(existing))
                    return;
                BEAST_EXPECT(existing->getFieldU64(sfMPTAmount) == 0);
            }
 
            std::uint32_t const redemptionDate = vaultImpaired->at(sfRedemptionDate);
            env.close(NetClock::time_point{NetClock::duration{redemptionDate}} + 1s);
 
            env(vault.withdraw({.depositor = alice, .id = vaultKeylet.key, .amount = redeemShares}),
                Ter(expected));
            env.close();
            if (expected != tesSUCCESS)
                return;
 
            if (removeAssetToken)
            {
                BEAST_EXPECT(!env.le(assetTokenKeylet));
            }
            else
            {
                auto const assetAfter = env.le(assetTokenKeylet);
                if (!BEAST_EXPECT(assetAfter))
                    return;
                BEAST_EXPECT(assetAfter->getFieldU64(sfMPTAmount) == 0);
            }
 
            auto const shareAfter = env.le(keylet::mptoken(shareId, alice.id()));
            if (withdrawAllAliceShares)
            {
                BEAST_EXPECT(!shareAfter);
            }
            else if (BEAST_EXPECT(shareAfter))
            {
                BEAST_EXPECT(shareAfter->getFieldU64(sfMPTAmount) == sharesBefore - sharesToRedeem);
            }
 
            auto const vaultAfter = env.le(vaultKeylet);
            if (!BEAST_EXPECT(vaultAfter))
                return;
            BEAST_EXPECT(vaultAfter->at(sfAssetsTotal) == totalBefore);
            BEAST_EXPECT(vaultAfter->at(sfLossUnrealized) == lossBefore);
            BEAST_EXPECT(vaultAfter->at(sfAssetsAvailable) == asset(0).value());
 
            auto const issuanceAfter = env.le(keylet::mptokenIssuance(shareId));
            if (!BEAST_EXPECT(issuanceAfter))
                return;
            BEAST_EXPECT(
                issuanceAfter->getFieldU64(sfOutstandingAmount) ==
                outstandingBefore - sharesToRedeem);
        };
 
        runScenario(
            all_, false /* removeAssetToken */, false /* withdrawAllAliceShares */, tesSUCCESS);
        runScenario(
            all_, false /* removeAssetToken */, true /* withdrawAllAliceShares */, tesSUCCESS);
        runScenario(
            all_, true /* removeAssetToken */, false /* withdrawAllAliceShares */, tesSUCCESS);
        runScenario(
            all_, true /* removeAssetToken */, true /* withdrawAllAliceShares */, tesSUCCESS);
        runScenario(
            all_ - fixCleanup3_4_0,
            false /* removeAssetToken */,
            false /* withdrawAllAliceShares */,
            tecINVARIANT_FAILED);
        runScenario(
            all_ - fixCleanup3_4_0,
            false /* removeAssetToken */,
            true /* withdrawAllAliceShares */,
            tecINVARIANT_FAILED);
        runScenario(
            all_ - fixCleanup3_4_0,
            true /* removeAssetToken */,
            false /* withdrawAllAliceShares */,
            tecINVARIANT_FAILED);
        runScenario(
            all_ - fixCleanup3_4_0,
            true /* removeAssetToken */,
            true /* withdrawAllAliceShares */,
            tecINVARIANT_FAILED);
    }
 
    // IOU analogue of the missing-MPToken case above. Alice removes her
    // zero-balance trust line after depositing, then burns one unit from her
    // scaled share balance after the vault is fully impaired. Bob's share
    // balance keeps this out of the sole-shareholder loss-waiver and
    // final-outstanding-share paths. A zero payout must not recreate Alice's
    // unsolicited trust line.
    void
    testBugIouZeroWithdrawMissingTrustLine()
    {
        using namespace test::jtx;
        using namespace loan_broker;
        using namespace loan;
        using namespace std::chrono_literals;
 
        Env env(*this, all_);
 
        Account const issuer{"issuer"};
        Account const owner{"owner"};
        Account const alice{"alice"};
        Account const bob{"bob"};
        Account const borrower{"borrower"};
 
        env.fund(XRP(100'000), issuer, owner, alice, bob, borrower);
        env.close();
        env(fset(issuer, asfDefaultRipple));
        env.close();
 
        PrettyAsset const asset = issuer["USD"];
        env.trust(asset(100), owner);
        env.trust(asset(100), alice);
        env.trust(asset(100), bob);
        env.trust(asset(100), borrower);
        env.close();
 
        env(pay(issuer, alice, asset(2)));
        env(pay(issuer, bob, asset(8)));
        env.close();
 
        Vault const vault{env};
        auto const [createTx, vaultKeylet, subscriptionDate] =
            vault.createClosedEnded({.owner = owner, .asset = asset, .subscriptionOffset = 60s});
        env(createTx);
        env.close();
 
        env(vault.deposit({.depositor = alice, .id = vaultKeylet.key, .amount = asset(2)}));
        env(vault.deposit({.depositor = bob, .id = vaultKeylet.key, .amount = asset(8)}));
        env.close();
 
        auto const assetLine = keylet::trustLine(alice, asset.raw().get<Issue>());
        if (!BEAST_EXPECT(env.le(assetLine)))
            return;
        env.trust(asset(0), alice);
        env.close();
        BEAST_EXPECT(!env.le(assetLine));
 
        vault.closePastSubscription(subscriptionDate);
 
        auto const brokerKeylet =
            keylet::loanBroker(owner.id(), SeqProxy::rawSequence(env.seq(owner)));
        env(set(owner, vaultKeylet.key));
        env.close();
 
        auto const sleBroker = env.le(brokerKeylet);
        if (!BEAST_EXPECT(sleBroker))
            return;
        auto const loanKeylet =
            keylet::loan(brokerKeylet.key, SeqProxy::rawSequence(sleBroker->at(sfLoanSequence)));
 
        env(set(borrower, brokerKeylet.key, asset(10).value()),
            kInterestRate(percentageToTenthBips(0)),
            kGracePeriod(60),
            kPaymentInterval(120),
            kPaymentTotal(10),
            Sig(sfCounterpartySignature, owner),
            Fee(env.current()->fees().base * 2),
            Ter(tesSUCCESS));
        env.close();
 
        auto const loanBefore = env.le(loanKeylet);
        if (!BEAST_EXPECT(loanBefore))
            return;
        std::uint32_t const dueDate = loanBefore->at(sfNextPaymentDueDate);
        env.close(NetClock::time_point{NetClock::duration{dueDate}} + 1s);
 
        env(manage(owner, loanKeylet.key, tfLoanImpair), Ter(tesSUCCESS));
        env.close();
 
        auto const vaultImpaired = env.le(vaultKeylet);
        if (!BEAST_EXPECT(vaultImpaired))
            return;
        BEAST_EXPECT(vaultImpaired->at(sfAssetsAvailable) == asset(0).value());
        BEAST_EXPECT(vaultImpaired->at(sfAssetsTotal) == vaultImpaired->at(sfLossUnrealized));
        Number const totalBefore = vaultImpaired->at(sfAssetsTotal);
        Number const lossBefore = vaultImpaired->at(sfLossUnrealized);
 
        MPTID const shareId = vaultImpaired->at(sfShareMPTID);
        auto const tokenAlice = env.le(keylet::mptoken(shareId, alice.id()));
        if (!BEAST_EXPECT(tokenAlice))
            return;
        std::uint64_t const sharesBefore = tokenAlice->getFieldU64(sfMPTAmount);
        // Default IOU vault scale is 6, so 2 USD mints 2e6 shares. Redeem one
        // leftover share; do not require 1:1 like the MPT case.
        BEAST_EXPECT(sharesBefore > 1);
        STAmount const redeemShares{MPTIssue{shareId}, Number(1)};
 
        std::uint32_t const redemptionDate = vaultImpaired->at(sfRedemptionDate);
        env.close(NetClock::time_point{NetClock::duration{redemptionDate}} + 1s);
 
        env(vault.withdraw({.depositor = alice, .id = vaultKeylet.key, .amount = redeemShares}),
            Ter(tesSUCCESS));
        env.close();
 
        // A regression in the View guard would recreate this line even though
        // no asset value was paid.
        BEAST_EXPECT(!env.le(assetLine));
 
        auto const shareAfter = env.le(keylet::mptoken(shareId, alice.id()));
        if (!BEAST_EXPECT(shareAfter))
            return;
        BEAST_EXPECT(shareAfter->getFieldU64(sfMPTAmount) == sharesBefore - 1);
 
        auto const vaultAfter = env.le(vaultKeylet);
        if (!BEAST_EXPECT(vaultAfter))
            return;
        BEAST_EXPECT(vaultAfter->at(sfAssetsTotal) == totalBefore);
        BEAST_EXPECT(vaultAfter->at(sfLossUnrealized) == lossBefore);
        BEAST_EXPECT(vaultAfter->at(sfAssetsAvailable) == asset(0).value());
    }
 
    // Same zero-payout withdrawal as testBugMptZeroWithdrawMissingHolding, but
    // the vault asset is XRP. addEmptyHolding is a no-op for native assets.
    // Sequence processing still touches the sender AccountRoot; a sponsored
    // fee leaves that XRP balance economically unchanged. After the
    // sponsored-withdraw fee-payer fix, deltaAssetsForParty collapses that
    // economically-zero XRP delta to absence, so tesSUCCESS takes the
    // missing-recipient-delta arm gated by zeroDeltaIsLegitimate. This test
    // covers that live SUCCESS path. Pre-fixCleanup3_4_0 still fails the
    // invariant.
    void
    testBugXrpZeroWithdrawSponsoredFee()
    {
        using namespace test::jtx;
        using namespace loan_broker;
        using namespace loan;
        using namespace std::chrono_literals;
 
        auto runScenario = [this](FeatureBitset features, TER expected) {
            testcase(
                std::string{"bug: XRP vault zero-value withdraw with sponsored fee"} +
                (features[fixCleanup3_4_0] ? " (post-fixCleanup3_4_0)" : " (pre-fixCleanup3_4_0)"));
 
            Env env(*this, features);
 
            Account const owner{"owner"};
            Account const alice{"alice"};
            Account const bob{"bob"};
            Account const borrower{"borrower"};
            Account const sponsor{"sponsor"};
 
            env.fund(XRP(100'000), owner, alice, bob, borrower, sponsor);
            env.close();
 
            PrettyAsset const asset{xrpIssue()};
            Vault const vault{env};
            auto const [createTx, vaultKeylet, subscriptionDate] = vault.createClosedEnded(
                {.owner = owner, .asset = asset, .subscriptionOffset = 60s});
            env(createTx);
            env.close();
 
            env(vault.deposit({.depositor = alice, .id = vaultKeylet.key, .amount = asset(2)}));
            env(vault.deposit({.depositor = bob, .id = vaultKeylet.key, .amount = asset(8)}));
            env.close();
 
            vault.closePastSubscription(subscriptionDate);
 
            auto const brokerKeylet =
                keylet::loanBroker(owner.id(), SeqProxy::rawSequence(env.seq(owner)));
            env(set(owner, vaultKeylet.key));
            env.close();
 
            auto const sleBroker = env.le(brokerKeylet);
            if (!BEAST_EXPECT(sleBroker))
                return;
            auto const loanKeylet = keylet::loan(
                brokerKeylet.key, SeqProxy::rawSequence(sleBroker->at(sfLoanSequence)));
 
            env(set(borrower, brokerKeylet.key, asset(10).value()),
                kInterestRate(percentageToTenthBips(0)),
                kGracePeriod(60),
                kPaymentInterval(120),
                kPaymentTotal(10),
                Sig(sfCounterpartySignature, owner),
                Fee(env.current()->fees().base * 2),
                Ter(tesSUCCESS));
            env.close();
 
            auto const loanBefore = env.le(loanKeylet);
            if (!BEAST_EXPECT(loanBefore))
                return;
            std::uint32_t const dueDate = loanBefore->at(sfNextPaymentDueDate);
            env.close(NetClock::time_point{NetClock::duration{dueDate}} + 1s);
 
            env(manage(owner, loanKeylet.key, tfLoanImpair), Ter(tesSUCCESS));
            env.close();
 
            auto const vaultImpaired = env.le(vaultKeylet);
            if (!BEAST_EXPECT(vaultImpaired))
                return;
            BEAST_EXPECT(vaultImpaired->at(sfAssetsAvailable) == asset(0).value());
            BEAST_EXPECT(vaultImpaired->at(sfAssetsTotal) == vaultImpaired->at(sfLossUnrealized));
            Number const totalBefore = vaultImpaired->at(sfAssetsTotal);
            Number const lossBefore = vaultImpaired->at(sfLossUnrealized);
 
            MPTID const shareId = vaultImpaired->at(sfShareMPTID);
            auto const tokenAlice = env.le(keylet::mptoken(shareId, alice.id()));
            if (!BEAST_EXPECT(tokenAlice))
                return;
            std::uint64_t const sharesBefore = tokenAlice->getFieldU64(sfMPTAmount);
            BEAST_EXPECT(sharesBefore == 2);
            STAmount const redeemShares{MPTIssue{shareId}, Number(1)};
 
            std::uint32_t const redemptionDate = vaultImpaired->at(sfRedemptionDate);
            env.close(NetClock::time_point{NetClock::duration{redemptionDate}} + 1s);
 
            auto const aliceBalanceBefore = env.balance(alice);
            auto const sponsorBalanceBefore = env.balance(sponsor);
            auto const fee = env.current()->fees().base;
 
            env(vault.withdraw({.depositor = alice, .id = vaultKeylet.key, .amount = redeemShares}),
                Fee(fee),
                sponsor::As(sponsor, spfSponsorFee),
                Sig(sfSponsorSignature, sponsor),
                Ter(expected));
            env.close();
 
            BEAST_EXPECT(env.balance(sponsor) == sponsorBalanceBefore - fee);
            BEAST_EXPECT(env.balance(alice) == aliceBalanceBefore);
 
            if (expected != tesSUCCESS)
                return;
 
            auto const shareAfter = env.le(keylet::mptoken(shareId, alice.id()));
            if (!BEAST_EXPECT(shareAfter))
                return;
            BEAST_EXPECT(shareAfter->getFieldU64(sfMPTAmount) == sharesBefore - 1);
 
            auto const vaultAfter = env.le(vaultKeylet);
            if (!BEAST_EXPECT(vaultAfter))
                return;
            BEAST_EXPECT(vaultAfter->at(sfAssetsTotal) == totalBefore);
            BEAST_EXPECT(vaultAfter->at(sfLossUnrealized) == lossBefore);
            BEAST_EXPECT(vaultAfter->at(sfAssetsAvailable) == asset(0).value());
        };
 
        runScenario(all_, tesSUCCESS);
        runScenario(all_ - fixCleanup3_4_0, tecINVARIANT_FAILED);
    }
 
    // addEmptyHolding() used to check isGlobalFrozen(issuer) and
    // !lsfDefaultRipple before the "line already exists" tecDUPLICATE
    // short circuit. doWithdraw() calls addEmptyHolding() for a
    // self-destination payout and only tolerates tecDUPLICATE, so
    // tecINTERNAL from a missing DefaultRipple flag aborted the
    // withdrawal. fixCleanup3_4_0 checks existence first and maps the
    // create-path DefaultRipple miss to terNO_RIPPLE. Global freeze on an
    // existing line is still rejected later by checkWithdrawFreeze.
    void
    testBugSelfWithdrawAfterIssuerClearsDefaultRipple()
    {
        using namespace test::jtx;
 
        auto runExistingLine = [this](
                                   FeatureBitset features,
                                   TER selfExpected,
                                   bool issuerGlobalFreeze = false) {
            Env env(*this, features);
            Account const issuer{"issuer"};
            Account const alice{"alice"};
            Account const bob{"bob"};
 
            env.fund(XRP(10'000), issuer, alice, bob);
            env.close();
            env(fset(issuer, asfDefaultRipple));
            env.close();
 
            PrettyAsset const usd{issuer["USD"]};
            Issue const usdIssue = usd.raw().get<Issue>();
            env(trust(alice, usd(10'000)));
            env(trust(bob, usd(10'000)));
            env.close();
            env(pay(issuer, alice, usd(1'000)));
            env.close();
 
            Vault const vault{env};
            auto [vaultTx, vaultKeylet] = vault.create({.owner = alice, .asset = usd});
            env(vaultTx);
            env.close();
 
            env(vault.deposit({.depositor = alice, .id = vaultKeylet.key, .amount = usd(500)}));
            env.close();
 
            env(vault.withdraw({.depositor = alice, .id = vaultKeylet.key, .amount = usd(50)}));
            env.close();
 
            env(fclear(issuer, asfDefaultRipple));
            env.close();
            if (issuerGlobalFreeze)
            {
                env(fset(issuer, asfGlobalFreeze));
                env.close();
            }
 
            BEAST_EXPECT(env.le(keylet::trustLine(alice.id(), usdIssue)));
 
            // Alice's USD line is unchanged; a later deposit still succeeds
            // unless the issuer is globally frozen.
            if (!issuerGlobalFreeze)
            {
                env(vault.deposit({.depositor = alice, .id = vaultKeylet.key, .amount = usd(10)}));
                env.close();
            }
 
            Number const destBefore = env.balance(alice, usd.raw()).number();
            Number const vaultBefore = env.le(vaultKeylet)->at(sfAssetsTotal);
            Number const withdrawAmt{50};
 
            env(vault.withdraw({.depositor = alice, .id = vaultKeylet.key, .amount = usd(50)}),
                Ter(selfExpected));
            env.close();
 
            Number const destAfter = env.balance(alice, usd.raw()).number();
            Number const vaultAfter = env.le(vaultKeylet)->at(sfAssetsTotal);
            if (isTesSuccess(selfExpected))
            {
                BEAST_EXPECT(destAfter == destBefore + withdrawAmt);
                BEAST_EXPECT(vaultAfter == vaultBefore - withdrawAmt);
            }
            else
            {
                BEAST_EXPECT(destAfter == destBefore);
                BEAST_EXPECT(vaultAfter == vaultBefore);
            }
 
            if (!issuerGlobalFreeze)
            {
                auto destTx =
                    vault.withdraw({.depositor = alice, .id = vaultKeylet.key, .amount = usd(50)});
                destTx[sfDestination] = bob.human();
                env(destTx);
                env.close();
            }
        };
 
        auto runDeletedLine = [this](FeatureBitset features, TER selfExpected) {
            Env env(*this, features);
            Account const issuer{"issuer"};
            Account const alice{"alice"};
 
            env.fund(XRP(10'000), issuer, alice);
            env.close();
            env(fset(issuer, asfDefaultRipple));
            env.close();
 
            PrettyAsset const usd{issuer["USD"]};
            Issue const usdIssue = usd.raw().get<Issue>();
            env(trust(alice, usd(10'000)));
            env.close();
            env(pay(issuer, alice, usd(500)));
            env.close();
 
            Vault const vault{env};
            auto [vaultTx, vaultKeylet] = vault.create({.owner = alice, .asset = usd});
            env(vaultTx);
            env.close();
 
            env(vault.deposit({.depositor = alice, .id = vaultKeylet.key, .amount = usd(500)}));
            env.close();
 
            env(trust(alice, usd(0)));
            env.close();
            BEAST_EXPECT(!env.le(keylet::trustLine(alice.id(), usdIssue)));
            env(fclear(issuer, asfDefaultRipple));
            env.close();
 
            env(vault.withdraw({.depositor = alice, .id = vaultKeylet.key, .amount = usd(50)}),
                Ter(selfExpected));
            env.close();
        };
 
        auto runCoverWithdraw = [this](FeatureBitset features, TER selfExpected) {
            using namespace loan_broker;
 
            Env env(*this, features);
            Account const issuer{"issuer"};
            Account const alice{"alice"};
 
            env.fund(XRP(10'000), issuer, alice);
            env.close();
            env(fset(issuer, asfDefaultRipple));
            env.close();
 
            PrettyAsset const usd{issuer["USD"]};
            Issue const usdIssue = usd.raw().get<Issue>();
            env(trust(alice, usd(10'000)));
            env.close();
            env(pay(issuer, alice, usd(1'000)));
            env.close();
 
            Vault const vault{env};
            auto const [createTx, vaultKeylet, subscriptionDate] = vault.createClosedEnded(
                {.owner = alice, .asset = usd, .subscriptionOffset = std::chrono::seconds{60}});
            (void)subscriptionDate;
            env(createTx);
            env.close();
 
            env(vault.deposit({.depositor = alice, .id = vaultKeylet.key, .amount = usd(500)}));
            env.close();
 
            auto const brokerKeylet =
                keylet::loanBroker(alice.id(), SeqProxy::rawSequence(env.seq(alice)));
            env(set(alice, vaultKeylet.key));
            env.close();
            env(coverDeposit(alice, brokerKeylet.key, usd(100).value()));
            env.close();
 
            env(fclear(issuer, asfDefaultRipple));
            env.close();
            BEAST_EXPECT(env.le(keylet::trustLine(alice.id(), usdIssue)));
 
            Number const destBefore = env.balance(alice, usd.raw()).number();
            Number const coverBefore = env.le(brokerKeylet)->at(sfCoverAvailable);
            Number const withdrawAmt{50};
 
            env(coverWithdraw(alice, brokerKeylet.key, usd(50).value()), Ter(selfExpected));
            env.close();
 
            Number const destAfter = env.balance(alice, usd.raw()).number();
            Number const coverAfter = env.le(brokerKeylet)->at(sfCoverAvailable);
            if (isTesSuccess(selfExpected))
            {
                BEAST_EXPECT(destAfter == destBefore + withdrawAmt);
                BEAST_EXPECT(coverAfter == coverBefore - withdrawAmt);
            }
            else
            {
                BEAST_EXPECT(destAfter == destBefore);
                BEAST_EXPECT(coverAfter == coverBefore);
            }
        };
 
        auto runDeletedCoverWithdraw = [this](FeatureBitset features, TER selfExpected) {
            using namespace loan_broker;
 
            Env env(*this, features);
            Account const issuer{"issuer"};
            Account const alice{"alice"};
 
            env.fund(XRP(10'000), issuer, alice);
            env.close();
            env(fset(issuer, asfDefaultRipple));
            env.close();
 
            PrettyAsset const usd{issuer["USD"]};
            Issue const usdIssue = usd.raw().get<Issue>();
            env(trust(alice, usd(10'000)));
            env.close();
            env(pay(issuer, alice, usd(600)));
            env.close();
 
            Vault const vault{env};
            auto const [createTx, vaultKeylet, subscriptionDate] = vault.createClosedEnded(
                {.owner = alice, .asset = usd, .subscriptionOffset = std::chrono::seconds{60}});
            (void)subscriptionDate;
            env(createTx);
            env.close();
 
            env(vault.deposit({.depositor = alice, .id = vaultKeylet.key, .amount = usd(500)}));
            env.close();
 
            auto const brokerKeylet =
                keylet::loanBroker(alice.id(), SeqProxy::rawSequence(env.seq(alice)));
            env(set(alice, vaultKeylet.key));
            env.close();
            env(coverDeposit(alice, brokerKeylet.key, usd(100).value()));
            env.close();
 
            env(trust(alice, usd(0)));
            env.close();
            BEAST_EXPECT(!env.le(keylet::trustLine(alice.id(), usdIssue)));
            env(fclear(issuer, asfDefaultRipple));
            env.close();
 
            env(coverWithdraw(alice, brokerKeylet.key, usd(50).value()), Ter(selfExpected));
            env.close();
        };
 
        auto runPrivateVault = [this](FeatureBitset features, TER selfExpected) {
            Env env(*this, features);
            Account const issuer{"issuer"};
            Account const alice{"alice"};
            Account const pdOwner{"pdOwner"};
            Account const credIssuer{"credIssuer"};
            std::string const credType = "credential";
 
            env.fund(XRP(10'000), issuer, alice, pdOwner, credIssuer);
            env.close();
            env(fset(issuer, asfDefaultRipple));
            env.close();
 
            PrettyAsset const usd{issuer["USD"]};
            env(trust(alice, usd(10'000)));
            env.close();
            env(pay(issuer, alice, usd(1'000)));
            env.close();
 
            Vault const vault{env};
            auto [vaultTx, vaultKeylet] =
                vault.create({.owner = alice, .asset = usd, .flags = tfVaultPrivate});
            env(vaultTx);
            env.close();
 
            pdomain::Credentials const credentials{{.issuer = credIssuer, .credType = credType}};
            env(pdomain::setTx(pdOwner, credentials));
            auto const domainId = pdomain::getNewDomain(env.meta());
            {
                auto domainTx = vault.set({.owner = alice, .id = vaultKeylet.key});
                domainTx[sfDomainID] = to_string(domainId);
                env(domainTx);
                env.close();
            }
 
            env(credentials::create(alice, credIssuer, credType));
            env(credentials::accept(alice, credIssuer, credType));
            env.close();
 
            env(vault.deposit({.depositor = alice, .id = vaultKeylet.key, .amount = usd(500)}));
            env.close();
 
            env(fclear(issuer, asfDefaultRipple));
            env.close();
 
            env(vault.withdraw({.depositor = alice, .id = vaultKeylet.key, .amount = usd(50)}),
                Ter(selfExpected));
            env.close();
        };
 
        testcase(
            "bug: VaultWithdraw to self fails with tecINTERNAL after issuer "
            "clears asfDefaultRipple even though the trust line exists "
            "(pre-fixCleanup3_4_0)");
        runExistingLine(all_ - fixCleanup3_4_0, tecINTERNAL);
 
        testcase(
            "bug: VaultWithdraw to self succeeds after issuer clears "
            "asfDefaultRipple when the trust line exists (post-fixCleanup3_4_0)");
        runExistingLine(all_, tesSUCCESS);
 
        testcase(
            "bug: VaultWithdraw to self with an existing line still gets "
            "tecFROZEN under asfGlobalFreeze (post-fixCleanup3_4_0)");
        runExistingLine(all_, tecFROZEN, true);
 
        testcase(
            "bug: VaultWithdraw to self fails with tecINTERNAL after issuer "
            "clears asfDefaultRipple and the trust line was deleted "
            "(pre-fixCleanup3_4_0)");
        runDeletedLine(all_ - fixCleanup3_4_0, tecINTERNAL);
 
        testcase(
            "bug: VaultWithdraw to self fails with terNO_RIPPLE after issuer "
            "clears asfDefaultRipple and the trust line was deleted "
            "(post-fixCleanup3_4_0)");
        runDeletedLine(all_, terNO_RIPPLE);
 
        testcase(
            "bug: LoanBrokerCoverWithdraw to self fails with tecINTERNAL after "
            "issuer clears asfDefaultRipple even though the trust line exists "
            "(pre-fixCleanup3_4_0)");
        runCoverWithdraw(all_ - fixCleanup3_4_0, tecINTERNAL);
 
        testcase(
            "bug: LoanBrokerCoverWithdraw to self succeeds after issuer clears "
            "asfDefaultRipple when the trust line exists (post-fixCleanup3_4_0)");
        runCoverWithdraw(all_, tesSUCCESS);
 
        testcase(
            "bug: LoanBrokerCoverWithdraw to self fails with tecINTERNAL after "
            "issuer clears asfDefaultRipple and the trust line was deleted "
            "(pre-fixCleanup3_4_0)");
        runDeletedCoverWithdraw(all_ - fixCleanup3_4_0, tecINTERNAL);
 
        testcase(
            "bug: LoanBrokerCoverWithdraw to self fails with terNO_RIPPLE after "
            "issuer clears asfDefaultRipple and the trust line was deleted "
            "(post-fixCleanup3_4_0)");
        runDeletedCoverWithdraw(all_, terNO_RIPPLE);
 
        testcase(
            "bug: private VaultWithdraw to self fails with tecINTERNAL after "
            "issuer clears asfDefaultRipple even though the trust line exists "
            "(pre-fixCleanup3_4_0)");
        runPrivateVault(all_ - fixCleanup3_4_0, tecINTERNAL);
 
        testcase(
            "bug: private VaultWithdraw to self succeeds after issuer clears "
            "asfDefaultRipple when the trust line exists (post-fixCleanup3_4_0)");
        runPrivateVault(all_, tesSUCCESS);
    }
 
    // Bug 1: a sponsored XRP VaultWithdraw to a distinct destination is
    // rejected because the vault invariant treats the holder's touched
    // but economically unchanged AccountRoot as a second payout
    // recipient. Sequence/ticket processing still touches the holder
    // while the sponsor pays the fee, so the holder's XRP delta is
    // present-zero and is not normalized away. If this happens on the
    // last Subscription ledger of a closed-ended vault, the holder
    // cannot retry until Redemption (tecTOO_SOON during Investment).
    //
    // Fixed by ValidVault::deltaAssetsForParty always collapsing an
    // economically-zero XRP delta to absence, regardless of who paid the
    // fee.
    void
    testBugSponsoredWithdrawZeroDeltaMisclassifiedAsSecondRecipient()
    {
        using namespace test::jtx;
 
        auto runScenario = [this](FeatureBitset features, TER expected) {
            Env env{*this, features};
            Account const owner{"owner"};
            Account const holder{"holder"};
            Account const destination{"destination"};
            Account const sponsor{"sponsor"};
            env.fund(XRP(10'000), owner, holder, destination, sponsor);
            env.close();
 
            constexpr std::uint32_t investmentPeriod = 14u * 24u * 60u * 60u;
            auto const [vault, vaultKeylet, subscriptionDate, redemptionDate] =
                makeClosedEndedVault(env, owner, xrpIssue(), 120u, investmentPeriod);
            BEAST_EXPECT(redemptionDate - subscriptionDate == investmentPeriod);
 
            env(vault.deposit(
                {.depositor = holder, .id = vaultKeylet.key, .amount = XRP(100).value()}));
            env.close();
 
            // Inclusive SubscriptionDate boundary: still Subscription, so an
            // ordinary withdrawal is allowed.
            closeToTime(env, Tp{D{subscriptionDate}});
 
            auto const vaultBefore = env.le(vaultKeylet);
            if (!BEAST_EXPECT(vaultBefore))
                return;
            auto const assetsTotalBefore = vaultBefore->at(sfAssetsTotal);
            auto const holderBalanceBefore = env.balance(holder);
            auto const destinationBalanceBefore = env.balance(destination);
            auto const sponsorBalanceBefore = env.balance(sponsor);
            auto const fee = env.current()->fees().base;
 
            auto withdraw = vault.withdraw(
                {.depositor = holder, .id = vaultKeylet.key, .amount = XRP(100).value()});
            withdraw[sfDestination] = destination.human();
            env(withdraw,
                Fee(fee),
                sponsor::As(sponsor, spfSponsorFee),
                Sig(sfSponsorSignature, sponsor),
                Ter(expected));
            env.close();
 
            auto const vaultAfter = env.le(vaultKeylet);
            if (!BEAST_EXPECT(vaultAfter))
                return;
            BEAST_EXPECT(env.balance(sponsor) == sponsorBalanceBefore - fee);
 
            if (expected == tesSUCCESS)
            {
                BEAST_EXPECT(vaultAfter->at(sfAssetsTotal) == assetsTotalBefore - XRP(100).value());
                BEAST_EXPECT(env.balance(holder) == holderBalanceBefore);
                BEAST_EXPECT(env.balance(destination) == destinationBalanceBefore + XRP(100));
                return;
            }
 
            // Invariant rollback: the payout and share burn are undone, but
            // sequence processing and the sponsored fee charge remain.
            BEAST_EXPECT(vaultAfter->at(sfAssetsTotal) == assetsTotalBefore);
            BEAST_EXPECT(env.balance(holder) == holderBalanceBefore);
            BEAST_EXPECT(env.balance(destination) == destinationBalanceBefore);
 
            // Once the ledger advances into Investment, the same holder
            // cannot retry until Redemption.
            auto retry = vault.withdraw(
                {.depositor = holder, .id = vaultKeylet.key, .amount = XRP(100).value()});
            retry[sfDestination] = destination.human();
            env(retry, Ter(tecTOO_SOON));
        };
 
        testcase(
            "bug: sponsored XRP withdrawal to a distinct destination misreads a "
            "touched-but-zero sender delta as a second recipient "
            "(pre-fixCleanup3_4_0)");
        runScenario(all_ - fixCleanup3_4_0, tecINVARIANT_FAILED);
 
        testcase(
            "bug: sponsored XRP withdrawal to a distinct destination succeeds "
            "(post-fixCleanup3_4_0)");
        runScenario(all_, tesSUCCESS);
    }
 
    // Bug 2: a co-signed fee sponsor named as the withdrawal's own
    // destination pays its fee from the same AccountRoot it is paid into,
    // so its net XRP delta is (payout - fee). The invariant never fee-
    // corrected the destination side at all, so this always failed the
    // equal-amount check against the vault's outflow (payout).
    //
    // Fixed by ValidVault::deltaAssetsForParty adding the fee back onto
    // whichever inspected party's AccountRoot actually paid it -- the
    // sender, or a distinct destination -- not just the sender.
    void
    testBugSponsorAsDestinationFeeMisappliedToPayout()
    {
        using namespace test::jtx;
 
        auto runScenario = [this](FeatureBitset features, TER expected) {
            Env env{*this, features};
            Account const owner{"owner"};
            Account const holder{"holder"};
            Account const sponsor{"sponsor"};
            env.fund(XRP(10'000), owner, holder, sponsor);
            env.close();
 
            Vault const vault{env};
            auto [vaultTx, vaultKeylet] = vault.create({.owner = owner, .asset = xrpIssue()});
            env(vaultTx);
            env.close();
 
            env(vault.deposit(
                {.depositor = holder, .id = vaultKeylet.key, .amount = XRP(100).value()}));
            env.close();
 
            auto const vaultBefore = env.le(vaultKeylet);
            if (!BEAST_EXPECT(vaultBefore))
                return;
            auto const assetsTotalBefore = vaultBefore->at(sfAssetsTotal);
            auto const sponsorBalanceBefore = env.balance(sponsor);
            auto const fee = env.current()->fees().base;
 
            // The sponsor both receives the withdrawal (as sfDestination)
            // and pays its own fee (co-signed) from the same AccountRoot.
            auto withdraw = vault.withdraw(
                {.depositor = holder, .id = vaultKeylet.key, .amount = XRP(100).value()});
            withdraw[sfDestination] = sponsor.human();
            env(withdraw,
                Fee(fee),
                sponsor::As(sponsor, spfSponsorFee),
                Sig(sfSponsorSignature, sponsor),
                Ter(expected));
            env.close();
 
            auto const vaultAfter = env.le(vaultKeylet);
            if (!BEAST_EXPECT(vaultAfter))
                return;
 
            if (expected == tesSUCCESS)
            {
                BEAST_EXPECT(vaultAfter->at(sfAssetsTotal) == assetsTotalBefore - XRP(100).value());
                // Paid the withdrawal, then separately debited for the fee
                // it chose to cover; net effect is payout minus fee.
                BEAST_EXPECT(env.balance(sponsor) == sponsorBalanceBefore + XRP(100) - fee);
                return;
            }
 
            BEAST_EXPECT(vaultAfter->at(sfAssetsTotal) == assetsTotalBefore);
            BEAST_EXPECT(env.balance(sponsor) == sponsorBalanceBefore - fee);
        };
 
        testcase(
            "bug: co-signed sponsor named as withdrawal destination has its "
            "own fee debit misread as breaking the payout equality "
            "(pre-fixCleanup3_4_0)");
        runScenario(all_ - fixCleanup3_4_0, tecINVARIANT_FAILED);
 
        testcase(
            "bug: co-signed sponsor named as withdrawal destination succeeds "
            "(post-fixCleanup3_4_0)");
        runScenario(all_, tesSUCCESS);
    }
 
    // Pre-funded fee sponsorship draws the fee from ltSponsorship.sfFeeAmount,
    // so feePayerAccountRoot must return nullopt rather than the sponsor's
    // AccountRoot. A bystander sponsor leaves that branch unexercised: the
    // result is only consulted by deltaAssetsForParty via `payer && *payer ==
    // id`. Naming the sponsor as sfDestination makes the early return
    // load-bearing -- returning the sponsor's id instead of nullopt would add
    // the fee back onto a balance that never paid it, and the equal-amount
    // check against the vault outflow would fail.
    //
    // Contrast testBugSponsorAsDestinationFeeMisappliedToPayout, where the
    // sponsor co-signs and so really does pay from its own AccountRoot.
    void
    testPrefundedFeeWithdraw()
    {
        using namespace test::jtx;
 
        auto runScenario = [this](
                               FeatureBitset features,
                               TER expected,
                               bool const sponsorIsDestination) {
            Env env{*this, features};
            Account const owner{"owner"};
            Account const holder{"holder"};
            Account const destination{"destination"};
            Account const sponsor{"sponsor"};
            env.fund(XRP(10'000), owner, holder, destination, sponsor);
            env.close();
 
            Vault const vault{env};
            auto [vaultTx, vaultKeylet] = vault.create({.owner = owner, .asset = xrpIssue()});
            env(vaultTx);
            env.close();
 
            env(vault.deposit(
                {.depositor = holder, .id = vaultKeylet.key, .amount = XRP(100).value()}));
            env.close();
 
            auto const fee = env.current()->fees().base;
            env(sponsor::set_fee(sponsor, 0, fee), sponsor::SponseeAcc(holder));
            env.close();
 
            auto const vaultBefore = env.le(vaultKeylet);
            if (!BEAST_EXPECT(vaultBefore))
                return;
            auto const assetsTotalBefore = vaultBefore->at(sfAssetsTotal);
            auto const holderBalanceBefore = env.balance(holder);
            auto const destinationBalanceBefore = env.balance(destination);
            auto const sponsorBalanceBefore = env.balance(sponsor);
 
            Account const& recipient = sponsorIsDestination ? sponsor : destination;
            auto withdraw = vault.withdraw(
                {.depositor = holder, .id = vaultKeylet.key, .amount = XRP(100).value()});
            withdraw[sfDestination] = recipient.human();
            env(withdraw, Fee(fee), sponsor::As(sponsor, spfSponsorFee), Ter(expected));
            env.close();
 
            auto const vaultAfter = env.le(vaultKeylet);
            if (!BEAST_EXPECT(vaultAfter))
                return;
            // Holder is economically unchanged (sequence only); the fee is
            // taken from the sponsorship object, not any AccountRoot.
            BEAST_EXPECT(env.balance(holder) == holderBalanceBefore);
 
            if (expected == tesSUCCESS)
            {
                BEAST_EXPECT(vaultAfter->at(sfAssetsTotal) == assetsTotalBefore - XRP(100).value());
                if (sponsorIsDestination)
                {
                    // The sponsor receives the payout and is not debited for
                    // the fee. The sponsor has to BE the destination for
                    // FeePayerType::SponsorPreFunded to matter.
                    BEAST_EXPECT(env.balance(sponsor) == sponsorBalanceBefore + XRP(100));
                }
                else
                {
                    BEAST_EXPECT(env.balance(destination) == destinationBalanceBefore + XRP(100));
                    BEAST_EXPECT(env.balance(sponsor) == sponsorBalanceBefore);
                }
                auto const sponsorship = env.le(keylet::sponsorship(sponsor, holder));
                if (!BEAST_EXPECT(sponsorship))
                    return;
                BEAST_EXPECT(!sponsorship->isFieldPresent(sfFeeAmount));
                return;
            }
 
            BEAST_EXPECT(vaultAfter->at(sfAssetsTotal) == assetsTotalBefore);
            BEAST_EXPECT(env.balance(sponsor) == sponsorBalanceBefore);
            if (!sponsorIsDestination)
                BEAST_EXPECT(env.balance(destination) == destinationBalanceBefore);
        };
 
        testcase(
            "pre-funded fee XRP withdrawal to a distinct destination succeeds "
            "(post-fixCleanup3_4_0)");
        runScenario(all_, tesSUCCESS, false);
 
        testcase(
            "bug: pre-funded sponsor named as withdrawal destination misreads "
            "the sender's touched-but-zero delta as a second recipient "
            "(pre-fixCleanup3_4_0)");
        runScenario(all_ - fixCleanup3_4_0, tecINVARIANT_FAILED, true);
 
        testcase(
            "bug: pre-funded sponsor named as withdrawal destination receives "
            "the full payout (post-fixCleanup3_4_0)");
        runScenario(all_, tesSUCCESS, true);
    }
 
    // Unsponsored third-party XRP withdrawal: the sender's AccountRoot moves
    // by exactly -fee. Pre-amendment, the sender-only fee correction then
    // collapses that to absence so the dual-recipient guard does not fire.
    void
    testUnsponsoredWithdrawToDistinctDestinationPreAmendment()
    {
        using namespace test::jtx;
 
        testcase(
            "unsponsored XRP withdrawal to a distinct destination succeeds "
            "(pre-fixCleanup3_4_0)");
 
        Env env{*this, all_ - fixCleanup3_4_0};
        Account const owner{"owner"};
        Account const holder{"holder"};
        Account const destination{"destination"};
        env.fund(XRP(10'000), owner, holder, destination);
        env.close();
 
        Vault const vault{env};
        auto [vaultTx, vaultKeylet] = vault.create({.owner = owner, .asset = xrpIssue()});
        env(vaultTx);
        env.close();
 
        env(vault.deposit(
            {.depositor = holder, .id = vaultKeylet.key, .amount = XRP(100).value()}));
        env.close();
 
        auto const vaultBefore = env.le(vaultKeylet);
        if (!BEAST_EXPECT(vaultBefore))
            return;
        auto const assetsTotalBefore = vaultBefore->at(sfAssetsTotal);
        auto const holderBalanceBefore = env.balance(holder);
        auto const destinationBalanceBefore = env.balance(destination);
        auto const fee = env.current()->fees().base;
 
        auto withdraw = vault.withdraw(
            {.depositor = holder, .id = vaultKeylet.key, .amount = XRP(100).value()});
        withdraw[sfDestination] = destination.human();
        env(withdraw, Fee(fee), Ter(tesSUCCESS));
        env.close();
 
        auto const vaultAfter = env.le(vaultKeylet);
        if (!BEAST_EXPECT(vaultAfter))
            return;
        BEAST_EXPECT(vaultAfter->at(sfAssetsTotal) == assetsTotalBefore - XRP(100).value());
        BEAST_EXPECT(env.balance(holder) == holderBalanceBefore - fee);
        BEAST_EXPECT(env.balance(destination) == destinationBalanceBefore + XRP(100));
    }
 
public:
    void
    run() override
    {
        testVaultWithdrawEqualityEnforced();
        testBugIssuerVaultDepositAtEdge();
        testBugMakeDeltaPosteriorScale();
        testBugMakeDeltaAnteriorScale();
        testVaultDepositCanonicalizeToZero();
        testBugDepositShareTruncationSubUlp();
        testVaultWithdrawCanonicalizeToZero();
        testBugVaultDustDebitCanonicalizesToNoOp();
        testBugVaultDepositOvercreditsAcrossScaleBoundary();
        testBugVaultLockedByPartialWithdraw();
        testVaultDepositNegativeBalanceFromOppositeLimit();
        testBug6LimitBypassWithShares();
        testBugClawbackRoundTripOvershoot();
        testBugWithdrawRoundTripOvershoot();
        testBugClawbackAfterLoanImpair();
        testBugMptZeroWithdrawMissingHolding();
        testBugIouZeroWithdrawMissingTrustLine();
        testBugXrpZeroWithdrawSponsoredFee();
        testBugSelfWithdrawAfterIssuerClearsDefaultRipple();
        testBugSponsoredWithdrawZeroDeltaMisclassifiedAsSecondRecipient();
        testBugSponsorAsDestinationFeeMisappliedToPayout();
        testPrefundedFeeWithdraw();
        testUnsponsoredWithdrawToDistinctDestinationPreAmendment();
    }
};
 
BEAST_DEFINE_TESTSUITE(VaultBugs, app, xrpl);
 
}  // namespace xrpl