Add an assert check to make sure no threads scheduled in nonauth model

luprex/core/cpp/world-accessor.cpp

@@ -312,7 +312,7 @@ LuaDefine(wait, "nticks",
         return LS.result();
     } else {
         // in an authoritative model, wait schedules a continuation.
-        w->thread_sched_.add(w->clock_ + n, w->lthread_thread_id_, w->lthread_place_id_);
+        w->schedule(w->clock_ + n, w->lthread_thread_id_, w->lthread_place_id_);
         lua_yield(L, 0);
         return LS.result();
     }

luprex/core/cpp/world-core.cpp

@@ -512,7 +512,7 @@ void World::invoke_lua(int64_t actor_id, int64_t place_id, const eng::string &ac
     LS.rawset(threads, tid, thinfo);
     LS.result();
 
-    thread_sched_.add(0, tid, place_id);
+    schedule(0, tid, place_id);
     run_scheduled_threads();
     assert(stack_is_clear());
 }
@@ -607,7 +607,7 @@ void World::invoke_plan(int64_t actor_id, int64_t place_id, const eng::string &a
     
     // Push the thread's ID into the runnable thread queue,
     // then run the thread queue.
-    thread_sched_.add(0, tid, place_id);
+    schedule(0, tid, place_id);
     run_scheduled_threads();
     assert(stack_is_clear());
 }
@@ -635,6 +635,11 @@ void World::invoke_lua_source(int64_t actor_id, int64_t place_id, const eng::str
     }
 }
 
+void World::schedule(int64_t clk, int64_t thid, int64_t plid) {
+    assert(is_authoritative());
+    thread_sched_.add(clk, thid, plid);
+}
+
 void World::run_scheduled_threads() {
     assert(stack_is_clear());
     lua_State *L = state();

luprex/core/cpp/world.hpp

@@ -264,6 +264,10 @@ public:
     int64_t alloc_id_predictable();
     
 private:
+    // Add a thread to the scheduler queue.
+    //
+    void schedule(int64_t clk, int64_t thid, int64_t plid);
+
     // Store a pointer to a world model into a lua registry.
     //
     static void store_global_pointer(lua_State *L, World *w);