Merge branch 'develop' into ximinez/emptydirectoryinvariant

* XRPLF/develop:
  refactor: Rename `ripple` namespace to `xrpl` (5982)
  refactor: Move JobQueue and related classes into xrpl.core module (6121)
  refactor: Rename `rippled` binary to `xrpld` (5983)
  refactor: rename info() to header() (6138)
  refactor: rename `LedgerInfo` to `LedgerHeader` (6136)
  refactor: clean up `RPCHelpers` (5684)
  chore: Fix docs readme and cmake (6122)
  chore: Clean up .gitignore and .gitattributes (6001)
  chore: Use updated secp256k1 recipe (6118)

src/libxrpl/ledger/ApplyView.cpp

@@ -254,6 +254,7 @@ ApplyView::dirRemove(
     uint256 const& key,
     bool keepRoot)
 {
+    keepRoot = false;
     auto node = peek(keylet::page(directory, page));
 
     if (!node)

src/test/app/Batch_test.cpp

@@ -427,7 +427,6 @@ class Batch_test : public beast::unit_test::suite
             auto const batchFee = batch::calcBatchFee(env, 0, 2);
             auto tx1 = batch::inner(pay(alice, bob, XRP(1)), seq + 1);
             tx1[jss::Fee] = "1.5";
-            env.set_parse_failure_expected(true);
             try
             {
                 env(batch::outer(alice, seq, batchFee, tfAllOrNothing),
@@ -439,7 +438,6 @@ class Batch_test : public beast::unit_test::suite
             {
                 BEAST_EXPECT(true);
             }
-            env.set_parse_failure_expected(false);
         }
 
         // temSEQ_AND_TICKET: Batch: inner txn cannot have both Sequence

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

@@ -1084,7 +1084,7 @@ ValidNewAccountRoot::finalize(
 
     JLOG(j.fatal()) << "Invariant failed: account root created illegally";
     return false;
-}  // namespace xrpl
+}
 
 //------------------------------------------------------------------------------
 
@@ -3566,4 +3566,42 @@ ValidVault::finalize(
     return true;
 }
 
+//------------------------------------------------------------------------------
+
+void
+NoEmptyDirectory::visitEntry(
+    bool isDelete,
+    std::shared_ptr<SLE const> const& before,
+    std::shared_ptr<SLE const> const& after)
+{
+    if (isDelete)
+        return;
+    if (before && before->getType() != ltDIR_NODE)
+        return;
+    if (after && after->getType() != ltDIR_NODE)
+        return;
+    if (!after->isFieldPresent(sfOwner))
+        // Not an account dir
+        return;
+
+    bad_ = after->at(sfIndexes).empty();
+}
+
+bool
+NoEmptyDirectory::finalize(
+    STTx const& tx,
+    TER const result,
+    XRPAmount const,
+    ReadView const& view,
+    beast::Journal const& j)
+{
+    if (bad_)
+    {
+        JLOG(j.fatal()) << "Invariant failed: empty owner directory.";
+        return false;
+    }
+
+    return true;
+}
+
 }  // namespace xrpl

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

@@ -902,6 +902,30 @@ public:
         beast::Journal const&);
 };
 
+/**
+ * @brief Invariants: An account's directory should never be empty
+ *
+ */
+class NoEmptyDirectory
+{
+    bool bad_ = false;
+
+public:
+    void
+    visitEntry(
+        bool,
+        std::shared_ptr<SLE const> const&,
+        std::shared_ptr<SLE const> const&);
+
+    bool
+    finalize(
+        STTx const&,
+        TER const,
+        XRPAmount const,
+        ReadView const&,
+        beast::Journal const&);
+};
+
 // additional invariant checks can be declared above and then added to this
 // tuple
 using InvariantChecks = std::tuple<
@@ -928,7 +952,8 @@ using InvariantChecks = std::tuple<
     ValidPseudoAccounts,
     ValidLoanBroker,
     ValidLoan,
-    ValidVault>;
+    ValidVault,
+    NoEmptyDirectory>;
 
 /**
  * @brief get a tuple of all invariant checks