Factor out isPseudoAccount

include/xrpl/protocol/detail/ledger_entries.macro

@@ -165,8 +165,8 @@ LEDGER_ENTRY(ltACCOUNT_ROOT, 0x0061, AccountRoot, account, ({
     {sfMintedNFTokens,       soeDEFAULT},
     {sfBurnedNFTokens,       soeDEFAULT},
     {sfFirstNFTokenSequence, soeOPTIONAL},
-    {sfAMMID,                soeOPTIONAL},
-    {sfVaultID,              soeOPTIONAL},
+    {sfAMMID,                soeOPTIONAL}, // pseudo-account designator
+    {sfVaultID,              soeOPTIONAL}, // pseudo-account designator
 }))
 
 /** A ledger object which contains a list of object identifiers.

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

@@ -884,8 +884,7 @@ ValidNewAccountRoot::visitEntry(
     {
         accountsCreated_++;
         accountSeq_ = (*after)[sfSequence];
-        pseudoAccount_ =
-            after->isFieldPresent(sfAMMID) || after->isFieldPresent(sfVaultID);
+        pseudoAccount_ = isPseudoAccount(after);
         flags_ = after->getFlags();
     }
 }

src/xrpld/ledger/View.h

@@ -25,6 +25,7 @@
 #include <xrpld/ledger/ReadView.h>
 
 #include <xrpl/beast/utility/Journal.h>
+#include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/MPTIssue.h>
 #include <xrpl/protocol/Protocol.h>
 #include <xrpl/protocol/Rate.h>
@@ -798,6 +799,21 @@ sharesToAssetsWithdraw(
     std::shared_ptr<SLE const> const& issuance,
     STAmount const& shares);
 
+// Returns true iff sleAcct is a pseudo-account.
+//
+// Returns false if sleAcct is
+// * NOT a pseudo-account OR
+// * NOT a ltACCOUNT_ROOT OR
+// * null pointer
+[[nodiscard]] bool
+isPseudoAccount(std::shared_ptr<SLE const> sleAcct);
+
+[[nodiscard]] inline bool
+isPseudoAccount(ReadView const& view, AccountID accountId)
+{
+    return isPseudoAccount(view.read(keylet::account(accountId)));
+}
+
 }  // namespace ripple
 
 #endif

src/xrpld/ledger/detail/View.cpp

@@ -2576,4 +2576,26 @@ sharesToAssetsWithdraw(
     return assets;
 }
 
+[[nodiscard]] bool
+isPseudoAccount(std::shared_ptr<SLE const> sleAcct)
+{
+    // Note, the list of the pseudo-account designator fields below MUST be
+    // maintained but it does NOT need to be amendment-gated, since a non-active
+    // amendment will not set any field, by definition. Specific properties of a
+    // pseudo-account are NOT checked here, that's what InvariantCheck is for.
+    static std::array<SField const*, 2> const fields =  //
+        {
+            &sfAMMID,    //
+            &sfVaultID,  //
+        };
+
+    // Intentionally use defensive coding here because it's cheap and makes the
+    // semantics of true return value clean.
+    return sleAcct && sleAcct->getType() == ltACCOUNT_ROOT &&
+        std::count_if(
+            fields.begin(), fields.end(), [&sleAcct](SField const* sf) -> bool {
+                return sleAcct->isFieldPresent(*sf);
+            }) > 0;
+}
+
 }  // namespace ripple