storage/registry: batch add no longer returns an iterator

src/entt/entity/registry.hpp

@@ -74,11 +74,13 @@ class basic_registry {
         }
 
         template<typename It>
-        std::enable_if_t<std::is_same_v<typename std::iterator_traits<It>::value_type, Entity>, typename storage<Entity, Component>::reverse_iterator_type>
+        std::enable_if_t<std::is_same_v<typename std::iterator_traits<It>::value_type, Entity>, void>
         assign(basic_registry &owner, It first, It last) {
-            auto it = this->construct(first, last);
-            std::for_each(first, last, [this, &owner](const auto entt) { construction.publish(entt, owner); });
-            return it;
+            this->construct(first, last);
+
+            if(!construction.empty()) {
+                std::for_each(first, last, [this, &owner](const auto entt) { construction.publish(entt, owner); });
+            }
         }
 
         void remove(basic_registry &owner, const Entity entt) {
@@ -641,13 +643,12 @@ public:
      * @tparam It Type of input iterator.
      * @param first An iterator to the first element of the range of entities.
      * @param last An iterator past the last element of the range of entities.
-     * @return An iterator to the list of components just created.
      */
     template<typename Component, typename It>
-    std::enable_if_t<std::is_same_v<typename std::iterator_traits<It>::value_type, entity_type>, typename pool_handler<Component>::reverse_iterator_type>
+    std::enable_if_t<std::is_same_v<typename std::iterator_traits<It>::value_type, entity_type>, void>
     assign(It first, It last) {
         ENTT_ASSERT(std::all_of(first, last, [this](const auto entity) { return valid(entity); }));
-        return assure<Component>().assign(*this, first, last);
+        assure<Component>().assign(*this, first, last);
     }
 
     /**

src/entt/entity/storage.hpp

@@ -164,8 +164,6 @@ public:
     using iterator_type = iterator<false>;
     /*! @brief Constant random access iterator type. */
     using const_iterator_type = iterator<true>;
-    /*! @brief Reverse iterator type. */
-    using reverse_iterator_type = std::reverse_iterator<iterator<false>>;
 
     /**
      * @brief Increases the capacity of a storage.
@@ -345,16 +343,13 @@ public:
      * @tparam It Type of forward iterator.
      * @param first An iterator to the first element of the range of entities.
      * @param last An iterator past the last element of the range of entities.
-     * @return An iterator to the list of instances just created and sorted the
-     * same of the entities.
      */
     template<typename It>
-    std::enable_if_t<std::is_same_v<typename std::iterator_traits<It>::value_type, entity_type>, reverse_iterator_type>
+    std::enable_if_t<std::is_same_v<typename std::iterator_traits<It>::value_type, entity_type>, void>
     construct(It first, It last) {
-        instances.insert(instances.end(), std::distance(first, last), object_type{});
+        instances.resize(instances.size() + std::distance(first, last), object_type{});
         // entity goes after component in case constructor throws
         underlying_type::construct(first, last);
-        return std::make_reverse_iterator(begin() + std::distance(first, last));
     }
 
     /**
@@ -581,8 +576,6 @@ public:
     using size_type = std::size_t;
     /*! @brief Random access iterator type. */
     using iterator_type = iterator;
-    /*! @brief Reverse iterator type. */
-    using reverse_iterator_type = std::reverse_iterator<iterator>;
 
     /**
      * @brief Returns an iterator to the beginning.
@@ -679,14 +672,11 @@ public:
      * @tparam It Type of forward iterator.
      * @param first An iterator to the first element of the range of entities.
      * @param last An iterator past the last element of the range of entities.
-     * @return An iterator to the list of instances just created and sorted the
-     * same of the entities.
      */
     template<typename It>
-    std::enable_if_t<std::is_same_v<typename std::iterator_traits<It>::value_type, entity_type>, reverse_iterator_type>
+    std::enable_if_t<std::is_same_v<typename std::iterator_traits<It>::value_type, entity_type>, void>
     construct(It first, It last) {
         underlying_type::construct(first, last);
-        return std::make_reverse_iterator(begin() + std::distance(first, last));
     }
 
     /*! @copydoc storage::sort */

test/entt/entity/registry.cpp

@@ -1191,17 +1191,11 @@ TEST(Registry, RangeAssign) {
     ASSERT_FALSE(registry.has<float>(e2));
 
     const auto view = registry.view<int, char>();
-    auto it = registry.assign<float>(view.begin(), view.end());
+    registry.assign<float>(view.begin(), view.end());
 
     ASSERT_TRUE(registry.has<float>(e0));
     ASSERT_TRUE(registry.has<float>(e1));
     ASSERT_FALSE(registry.has<float>(e2));
-
-    *it = 0.f;
-    *(it+1) = 1.f;
-
-    ASSERT_EQ(registry.get<float>(*view.begin()), 0.f);
-    ASSERT_EQ(registry.get<float>(*(++view.begin())), 1.f);
 }
 
 TEST(Registry, RangeRemove) {

test/entt/entity/storage.cpp

@@ -100,7 +100,7 @@ TEST(Storage, BatchAdd) {
 
     entities[0] = entt::entity{3};
     entities[1] = entt::entity{42};
-    auto it = pool.construct(std::begin(entities), std::end(entities));
+    pool.construct(std::begin(entities), std::end(entities));
 
     ASSERT_TRUE(pool.has(entities[0]));
     ASSERT_TRUE(pool.has(entities[1]));
@@ -109,12 +109,6 @@ TEST(Storage, BatchAdd) {
     ASSERT_EQ(pool.size(), 2u);
     ASSERT_EQ(pool.get(entities[0]), 0);
     ASSERT_EQ(pool.get(entities[1]), 0);
-
-    it[0] = 1;
-    it[1] = 2;
-
-    ASSERT_EQ(pool.get(entities[0]), 1);
-    ASSERT_EQ(pool.get(entities[1]), 2);
 }
 
 TEST(Storage, BatchAddEmptyType) {