Add InvariantChecks for if OwnerCount < SponsoredOwnerCount

src/test/app/Invariants_test.cpp

@@ -101,7 +101,8 @@ class Invariants_test : public beast::unit_test::suite
                 if (messages.find(m) == std::string::npos)
                 {
                     // uncomment if you want to log the invariant failure
-                    // std::cerr << "   --> " << m << std::endl;
+                    // std::cerr << " expected --> " << m << std::endl;
+                    // std::cerr << " actual   --> " << messages << std::endl;
                     fail();
                 }
             }
@@ -3516,6 +3517,26 @@ class Invariants_test : public beast::unit_test::suite
             });
         }
 
+        {
+            auto const expect_message = "OwnerCount must be greater than or equal to SponsoredOwnerCount.";
+
+            doInvariantCheck({{expect_message}}, [&](Account const& A1, Account const& A2, ApplyContext& ac) {
+                auto const sle = ac.view().peek(keylet::account(A1.id()));
+                if (!sle)
+                    return false;
+                sle->setFieldU32(sfOwnerCount, 0);
+                sle->setFieldU32(sfSponsoredOwnerCount, 1);
+                ac.view().update(sle);
+
+                auto const sle2 = ac.view().peek(keylet::account(A2.id()));
+                if (!sle2)
+                    return false;
+                sle2->setFieldU32(sfSponsoringOwnerCount, 1);
+                ac.view().update(sle2);
+                return true;
+            });
+        }
+
         {
             auto const expect_message =
                 "Invariant failed: Net delta of SponsoringAccountCount does "

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

@@ -3287,6 +3287,17 @@ SponsorshipOwnerCountsMatch::visitEntry(
         return 0;
     };
 
+    auto getOwnerCount = [](std::shared_ptr<SLE const> const& sle) -> std::uint32_t {
+        if (sle && sle->getType() == ltACCOUNT_ROOT)
+            return sle->getFieldU32(sfOwnerCount);
+        return 0;
+    };
+    auto getSponsoredOwnerCount = [](std::shared_ptr<SLE const> const& sle) -> std::uint32_t {
+        if (sle && sle->getType() == ltACCOUNT_ROOT)
+            return sle->getFieldU32(sfSponsoredOwnerCount);
+        return 0;
+    };
+
     std::int64_t const beforeSponsored = getSponsored(before);
     std::int64_t const afterSponsored = getSponsored(after);
     std::int64_t const beforeSponsoring = getSponsoring(before);
@@ -3294,6 +3305,9 @@ SponsorshipOwnerCountsMatch::visitEntry(
 
     deltaSponsoredOwnerCount_ += (afterSponsored - beforeSponsored);
     deltaSponsoringOwnerCount_ += (afterSponsoring - beforeSponsoring);
+
+    if (getOwnerCount(after) < getSponsoredOwnerCount(after))
+        invalidOwnerCountLessThanSponsoredOwnerCount_ += 1;
 }
 
 bool
@@ -3306,6 +3320,12 @@ SponsorshipOwnerCountsMatch::finalize(STTx const&, TER const, XRPAmount const, R
         return false;
     }
 
+    if (invalidOwnerCountLessThanSponsoredOwnerCount_ > 0)
+    {
+        JLOG(j.fatal()) << "Invariant failed: OwnerCount must be greater than or equal to SponsoredOwnerCount.";
+        return false;
+    }
+
     return true;
 }
 

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

@@ -401,11 +401,13 @@ public:
  * The following check is made for every transaction:
  *  - The sum of all per-account deltas of `sfSponsoredOwnerCount` equals
  *    the sum of all per-account deltas of `sfSponsoringOwnerCount`.
+ *  - Account OwnerCount must be greater than or equal to SponsoredOwnerCount.
  */
 class SponsorshipOwnerCountsMatch
 {
     std::int64_t deltaSponsoredOwnerCount_ = 0;
     std::int64_t deltaSponsoringOwnerCount_ = 0;
+    std::uint64_t invalidOwnerCountLessThanSponsoredOwnerCount_ = 0;
 
 public:
     void