Reserve entity #0

tests/zecsy.cpp

@@ -10,6 +10,7 @@ TEST_CASE("Create a single entity and verify its existence")
     world w;
  
     auto e = w.make_entity();
+    
     REQUIRE(w.is_alive(e));
 }
 
@@ -19,5 +20,15 @@ TEST_CASE("Destroy an entity and ensure it no longer exists in the world")
     
     auto e = w.make_entity();
     w.destroy_entity(e);
+    
     REQUIRE_FALSE(w.is_alive(e));
 }
+
+TEST_CASE("Entity #0 should be reserved and never used")
+{
+    world w;
+    
+    auto e = w.make_entity();
+
+    REQUIRE(e != 0);
+}

zecsy.hpp

@@ -31,11 +31,8 @@ namespace zecsy
 
     inline entity_id world::make_entity()
     {
-        auto id = entity_counter;
+        auto id = ++entity_counter;
         entities_bitset.set(id);
-    
-        entity_counter++;
-    
         return id;
     }