Add MPT support to DEX:

* Payment
* OfferCreate
* CheckCash
* All AMM transactions
* Pathfinding

Retire FlowCross feature

include/xrpl/protocol/AMMCore.h

@@ -22,7 +22,7 @@
 
 #include <xrpl/basics/Number.h>
 #include <xrpl/protocol/AccountID.h>
-#include <xrpl/protocol/Issue.h>
+#include <xrpl/protocol/Asset.h>
 #include <xrpl/protocol/TER.h>
 #include <xrpl/protocol/UintTypes.h>
 
@@ -59,14 +59,14 @@ ammAccountID(
 /** Calculate Liquidity Provider Token (LPT) Currency.
  */
 Currency
-ammLPTCurrency(Currency const& cur1, Currency const& cur2);
+ammLPTCurrency(Asset const& asset1, Asset const& asset2);
 
 /** Calculate LPT Issue from AMM asset pair.
  */
 Issue
 ammLPTIssue(
-    Currency const& cur1,
-    Currency const& cur2,
+    Asset const& asset1,
+    Asset const& asset2,
     AccountID const& ammAccountID);
 
 /** Validate the amount.
@@ -77,19 +77,19 @@ ammLPTIssue(
 NotTEC
 invalidAMMAmount(
     STAmount const& amount,
-    std::optional<std::pair<Issue, Issue>> const& pair = std::nullopt,
+    std::optional<std::pair<Asset, Asset>> const& pair = std::nullopt,
     bool validZero = false);
 
 NotTEC
 invalidAMMAsset(
-    Issue const& issue,
-    std::optional<std::pair<Issue, Issue>> const& pair = std::nullopt);
+    Asset const& asset,
+    std::optional<std::pair<Asset, Asset>> const& pair = std::nullopt);
 
 NotTEC
 invalidAMMAssetPair(
-    Issue const& issue1,
-    Issue const& issue2,
-    std::optional<std::pair<Issue, Issue>> const& pair = std::nullopt);
+    Asset const& asset1,
+    Asset const& asset2,
+    std::optional<std::pair<Asset, Asset>> const& pair = std::nullopt);
 
 /** Get time slot of the auction slot.
  */

include/xrpl/protocol/AmountConversions.h

@@ -21,6 +21,7 @@
 #define RIPPLE_PROTOCOL_AMOUNTCONVERSION_H_INCLUDED
 
 #include <xrpl/protocol/IOUAmount.h>
+#include <xrpl/protocol/Protocol.h>
 #include <xrpl/protocol/STAmount.h>
 #include <xrpl/protocol/XRPAmount.h>
 
@@ -29,11 +30,12 @@
 namespace ripple {
 
 inline STAmount
-toSTAmount(IOUAmount const& iou, Issue const& iss)
+toSTAmount(IOUAmount const& iou, Asset const& asset)
 {
+    XRPL_ASSERT(asset.holds<Issue>(), "ripple::toSTAmount : is Issue");
     bool const isNeg = iou.signum() < 0;
     std::uint64_t const umant = isNeg ? -iou.mantissa() : iou.mantissa();
-    return STAmount(iss, umant, iou.exponent(), isNeg, STAmount::unchecked());
+    return STAmount(asset, umant, iou.exponent(), isNeg, STAmount::unchecked());
 }
 
 inline STAmount
@@ -51,14 +53,25 @@ toSTAmount(XRPAmount const& xrp)
 }
 
 inline STAmount
-toSTAmount(XRPAmount const& xrp, Issue const& iss)
+toSTAmount(XRPAmount const& xrp, Asset const& asset)
 {
-    XRPL_ASSERT(
-        isXRP(iss.account) && isXRP(iss.currency),
-        "ripple::toSTAmount : is XRP");
+    XRPL_ASSERT(isXRP(asset), "ripple::toSTAmount : is XRP");
     return toSTAmount(xrp);
 }
 
+inline STAmount
+toSTAmount(MPTAmount const& mpt)
+{
+    return STAmount(mpt, noMPT());
+}
+
+inline STAmount
+toSTAmount(MPTAmount const& mpt, Asset const& asset)
+{
+    XRPL_ASSERT(asset.holds<MPTIssue>(), "ripple::toSTAmount : is MPT");
+    return STAmount(mpt, asset.get<MPTIssue>());
+}
+
 template <class T>
 T
 toAmount(STAmount const& amt) = delete;
@@ -100,6 +113,21 @@ toAmount<XRPAmount>(STAmount const& amt)
     return XRPAmount(sMant);
 }
 
+template <>
+inline MPTAmount
+toAmount<MPTAmount>(STAmount const& amt)
+{
+    XRPL_ASSERT(
+        amt.holds<MPTIssue>() && amt.mantissa() <= maxMPTokenAmount &&
+            amt.exponent() == 0,
+        "ripple::toAmount<MPTAmount> : maximum mantissa");
+    bool const isNeg = amt.negative();
+    std::int64_t const sMant =
+        isNeg ? -std::int64_t(amt.mantissa()) : amt.mantissa();
+
+    return MPTAmount(sMant);
+}
+
 template <class T>
 T
 toAmount(IOUAmount const& amt) = delete;
@@ -122,26 +150,39 @@ toAmount<XRPAmount>(XRPAmount const& amt)
     return amt;
 }
 
+template <class T>
+T
+toAmount(MPTAmount const& amt) = delete;
+
+template <>
+inline MPTAmount
+toAmount<MPTAmount>(MPTAmount const& amt)
+{
+    return amt;
+}
+
 template <typename T>
 T
 toAmount(
-    Issue const& issue,
+    Asset const& asset,
     Number const& n,
     Number::rounding_mode mode = Number::getround())
 {
     saveNumberRoundMode rm(Number::getround());
-    if (isXRP(issue))
+    if (isXRP(asset))
         Number::setround(mode);
 
     if constexpr (std::is_same_v<IOUAmount, T>)
         return IOUAmount(n);
     else if constexpr (std::is_same_v<XRPAmount, T>)
         return XRPAmount(static_cast<std::int64_t>(n));
+    else if constexpr (std::is_same_v<MPTAmount, T>)
+        return MPTAmount(static_cast<std::int64_t>(n));
     else if constexpr (std::is_same_v<STAmount, T>)
     {
-        if (isXRP(issue))
-            return STAmount(issue, static_cast<std::int64_t>(n));
-        return STAmount(issue, n.mantissa(), n.exponent());
+        if (isXRP(asset))
+            return STAmount(asset, static_cast<std::int64_t>(n));
+        return STAmount(asset, n.mantissa(), n.exponent());
     }
     else
     {
@@ -152,18 +193,31 @@ toAmount(
 
 template <typename T>
 T
-toMaxAmount(Issue const& issue)
+toMaxAmount(Asset const& asset)
 {
     if constexpr (std::is_same_v<IOUAmount, T>)
         return IOUAmount(STAmount::cMaxValue, STAmount::cMaxOffset);
     else if constexpr (std::is_same_v<XRPAmount, T>)
         return XRPAmount(static_cast<std::int64_t>(STAmount::cMaxNativeN));
+    else if constexpr (std::is_same_v<MPTAmount, T>)
+        return MPTAmount(maxMPTokenAmount);
     else if constexpr (std::is_same_v<STAmount, T>)
     {
-        if (isXRP(issue))
-            return STAmount(
-                issue, static_cast<std::int64_t>(STAmount::cMaxNativeN));
-        return STAmount(issue, STAmount::cMaxValue, STAmount::cMaxOffset);
+        return std::visit(
+            []<ValidIssueType TIss>(TIss const& issue) {
+                if constexpr (std::is_same_v<TIss, Issue>)
+                {
+                    if (isXRP(issue))
+                        return STAmount(
+                            issue,
+                            static_cast<std::int64_t>(STAmount::cMaxNativeN));
+                    return STAmount(
+                        issue, STAmount::cMaxValue, STAmount::cMaxOffset);
+                }
+                else
+                    return STAmount(issue, maxMPTokenAmount);
+            },
+            asset.value());
     }
     else
     {
@@ -174,23 +228,25 @@ toMaxAmount(Issue const& issue)
 
 inline STAmount
 toSTAmount(
-    Issue const& issue,
+    Asset const& asset,
     Number const& n,
     Number::rounding_mode mode = Number::getround())
 {
-    return toAmount<STAmount>(issue, n, mode);
+    return toAmount<STAmount>(asset, n, mode);
 }
 
 template <typename T>
-Issue
-getIssue(T const& amt)
+Asset
+getAsset(T const& amt)
 {
     if constexpr (std::is_same_v<IOUAmount, T>)
         return noIssue();
     else if constexpr (std::is_same_v<XRPAmount, T>)
         return xrpIssue();
+    else if constexpr (std::is_same_v<MPTAmount, T>)
+        return noMPT();
     else if constexpr (std::is_same_v<STAmount, T>)
-        return amt.issue();
+        return amt.asset();
     else
     {
         constexpr bool alwaysFalse = !std::is_same_v<T, T>;
@@ -206,6 +262,8 @@ get(STAmount const& a)
         return a.iou();
     else if constexpr (std::is_same_v<XRPAmount, T>)
         return a.xrp();
+    else if constexpr (std::is_same_v<MPTAmount, T>)
+        return a.mpt();
     else if constexpr (std::is_same_v<STAmount, T>)
         return a;
     else

include/xrpl/protocol/Asset.h

@@ -21,21 +21,20 @@
 #define RIPPLE_PROTOCOL_ASSET_H_INCLUDED
 
 #include <xrpl/basics/base_uint.h>
+#include <xrpl/protocol/Concepts.h>
 #include <xrpl/protocol/Issue.h>
 #include <xrpl/protocol/MPTIssue.h>
 
 namespace ripple {
 
-class Asset;
-
-template <typename TIss>
-concept ValidIssueType =
-    std::is_same_v<TIss, Issue> || std::is_same_v<TIss, MPTIssue>;
-
-template <typename A>
-concept AssetType =
-    std::is_convertible_v<A, Asset> || std::is_convertible_v<A, Issue> ||
-    std::is_convertible_v<A, MPTIssue> || std::is_convertible_v<A, MPTID>;
+template <typename T>
+    requires(
+        std::is_same_v<T, XRPAmount> || std::is_same_v<T, IOUAmount> ||
+        std::is_same_v<T, MPTAmount>)
+struct AmountType
+{
+    using amount_type = T;
+};
 
 /* Asset is an abstraction of three different issue types: XRP, IOU, MPT.
  * For historical reasons, two issue types XRP and IOU are wrapped in Issue
@@ -46,6 +45,10 @@ class Asset
 {
 public:
     using value_type = std::variant<Issue, MPTIssue>;
+    using AmtType = std::variant<
+        AmountType<XRPAmount>,
+        AmountType<IOUAmount>,
+        AmountType<MPTAmount>>;
 
 private:
     value_type issue_;
@@ -92,12 +95,15 @@ class Asset
     void
     setJson(Json::Value& jv) const;
 
-    bool
+    constexpr bool
     native() const
     {
         return holds<Issue>() && get<Issue>().native();
     }
 
+    constexpr AmtType
+    getAmountType() const;
+
     friend constexpr bool
     operator==(Asset const& lhs, Asset const& rhs);
 
@@ -145,6 +151,22 @@ Asset::value() const
     return issue_;
 }
 
+constexpr Asset::AmtType
+Asset::getAmountType() const
+{
+    return std::visit(
+        [&]<ValidIssueType TIss>(TIss const& issue) -> AmtType {
+            constexpr AmountType<XRPAmount> xrp;
+            constexpr AmountType<IOUAmount> iou;
+            constexpr AmountType<MPTAmount> mpt;
+            if constexpr (std::is_same_v<TIss, Issue>)
+                return native() ? AmtType(xrp) : AmtType(iou);
+            else
+                return AmtType(mpt);
+        },
+        issue_);
+}
+
 constexpr bool
 operator==(Asset const& lhs, Asset const& rhs)
 {
@@ -222,6 +244,50 @@ assetFromJson(Json::Value const& jv);
 Json::Value
 to_json(Asset const& asset);
 
+inline bool
+isConsistent(Asset const& issue)
+{
+    return std::visit(
+        [&]<typename TIss>(TIss const& issue_) {
+            if constexpr (std::is_same_v<TIss, Issue>)
+                return isConsistent(issue_);
+            else
+                return true;
+        },
+        issue.value());
+}
+
+inline bool
+validAsset(Asset const& issue)
+{
+    return std::visit(
+        [&]<typename TIss>(TIss const& issue_) {
+            if constexpr (std::is_same_v<TIss, Issue>)
+                return isConsistent(issue_) && issue_.currency != badCurrency();
+            else
+                return true;
+        },
+        issue.value());
+}
+
+template <class Hasher>
+void
+hash_append(Hasher& h, Asset const& r)
+{
+    using beast::hash_append;
+    std::visit(
+        [&]<ValidIssueType TIss>(TIss const& issue) {
+            if constexpr (std::is_same_v<TIss, Issue>)
+                hash_append(h, issue);
+            else
+                hash_append(h, issue);
+        },
+        r.value());
+}
+
+std::ostream&
+operator<<(std::ostream& os, Asset const& x);
+
 }  // namespace ripple
 
 #endif  // RIPPLE_PROTOCOL_ASSET_H_INCLUDED