Use addWithoutSigningFields in jtx::sign

src/ripple/test/jtx/impl/Env_test.cpp

@@ -561,6 +561,24 @@ public:
                 );
     }
 
+    // Test that jtx can re-sign a transaction that's already been signed.
+    void testResignSigned()
+    {
+        using namespace jtx;
+        Env env(*this);
+
+        env.fund(XRP(10000), "alice");
+        auto const baseFee = env.open()->fees().base;
+        std::uint32_t const aliceSeq = env.seq ("alice");
+        
+        // Sign jsonNoop.
+        Json::Value jsonNoop = env.json (
+            noop ("alice"), fee(baseFee), seq(aliceSeq), sig("alice"));
+        // Re-sign jsonNoop.
+        JTx jt = env.jt (jsonNoop);
+        env (jt);
+    }
+
     void
     run()
     {
@@ -580,6 +598,7 @@ public:
         testAdvance();
         testClose();
         testPath();
+        testResignSigned();
     }
 };
 

src/ripple/test/jtx/impl/utility.cpp

@@ -50,7 +50,7 @@ sign (Json::Value& jv,
         strHex(account.pk().slice());
     Serializer ss;
     ss.add32 (HashPrefix::txSign);
-    parse(jv).add(ss);
+    parse(jv).addWithoutSigningFields(ss);
     auto const sig = ripple::sign(
         *publicKeyType(account.pk().slice()),
             account.sk(), ss.slice());