fix for XRPLF#38

Author: RichardAH

src/ripple/app/hook/Enum.h

@@ -132,6 +132,7 @@ namespace hook
             NESTING_LIMIT = 84,         // the hook nested blocks/loops/ifs beyond 16 levels
             SECTIONS_OUT_OF_SEQUENCE = 85,  // the wasm contained sections out of sequence
             CUSTOM_SECTION_DISALLOWED = 86, // the wasm contained a custom section (id=0)
+            INTERNAL_ERROR       = 87,  // an internal error described by the log text
             // RH NOTE: only HookSet msgs got log codes, possibly all Hook log lines should get a code? 
         };
     };

src/ripple/app/tx/impl/SetHook.cpp

@@ -1260,7 +1260,13 @@ SetHook::setHook()
 
         // if there is only an existing hook, without a HookSetObj then it is
         // logically impossible for the operation to not be NOOP
-        assert(hookSetObj || op == hsoNOOP);
+        if(!hookSetObj && op != hsoNOOP)
+        {
+            JLOG(ctx.j.warn())
+                << "HookSet(" << hook::log::INTERNAL_ERROR << ")[" << HS_ACC()
+                << "]: Logic error. !hookSetObj && op != hsoNOOP";
+            return tecINTERNAL;
+        }
 
         switch (op)
         {