Initial commit - restart from existing code

lib/All/entt/test/example/entity_copy.cpp

@@ -0,0 +1,124 @@
+#include <gtest/gtest.h>
+#include <entt/core/hashed_string.hpp>
+#include <entt/core/utility.hpp>
+#include <entt/entity/registry.hpp>
+#include <entt/entity/storage.hpp>
+#include <entt/meta/factory.hpp>
+#include <entt/meta/meta.hpp>
+#include <entt/meta/policy.hpp>
+#include <entt/meta/resolve.hpp>
+
+enum class my_entity : entt::id_type {};
+
+template<typename Type>
+// NOLINTNEXTLINE(*-exception-escape)
+struct meta_mixin: Type {
+    using allocator_type = typename Type::allocator_type;
+    using element_type = typename Type::element_type;
+
+    explicit meta_mixin(const allocator_type &allocator);
+};
+
+template<typename Type, typename Entity>
+struct entt::storage_type<Type, Entity> {
+    using type = meta_mixin<basic_storage<Type, Entity>>;
+};
+
+template<typename Type>
+meta_mixin<Type>::meta_mixin(const allocator_type &allocator)
+    : Type{allocator} {
+    using namespace entt::literals;
+
+    entt::meta_factory<element_type>{}
+        // cross registry, same type
+        .template func<entt::overload<entt::storage_for_t<element_type, entt::entity> &(const entt::id_type)>(&entt::basic_registry<entt::entity>::storage<element_type>), entt::as_ref_t>("storage"_hs)
+        // cross registry, different types
+        .template func<entt::overload<entt::storage_for_t<element_type, my_entity> &(const entt::id_type)>(&entt::basic_registry<my_entity>::storage<element_type>), entt::as_ref_t>("storage"_hs);
+}
+
+template<typename Type>
+struct EntityCopy: testing::Test {
+    using type = Type;
+};
+
+using EntityCopyTypes = ::testing::Types<entt::basic_registry<entt::entity>, entt::basic_registry<my_entity>>;
+
+TYPED_TEST_SUITE(EntityCopy, EntityCopyTypes, );
+
+TEST(EntityCopy, SameRegistry) {
+    using namespace entt::literals;
+
+    entt::registry registry{};
+    auto &&custom = registry.storage<double>("custom"_hs);
+
+    const auto src = registry.create();
+    const auto dst = registry.create();
+
+    custom.emplace(src, 1.);
+    registry.emplace<int>(src, 2);
+    registry.emplace<char>(src, 'c');
+
+    ASSERT_EQ(registry.storage<entt::entity>().size(), 2u);
+    ASSERT_TRUE(custom.contains(src));
+    ASSERT_FALSE(custom.contains(dst));
+    ASSERT_TRUE((registry.all_of<int, char>(src)));
+    ASSERT_FALSE((registry.any_of<int, char>(dst)));
+
+    for(auto [id, storage]: registry.storage()) {
+        // discard the custom storage because why not, this is just an example after all
+        if(id != "custom"_hs && storage.contains(src)) {
+            storage.push(dst, storage.value(src));
+        }
+    }
+
+    ASSERT_EQ(registry.storage<entt::entity>().size(), 2u);
+    ASSERT_TRUE(custom.contains(src));
+    ASSERT_FALSE(custom.contains(dst));
+    ASSERT_TRUE((registry.all_of<int, char>(src)));
+    ASSERT_TRUE((registry.all_of<int, char>(dst)));
+
+    ASSERT_EQ(registry.get<int>(dst), 2);
+    ASSERT_EQ(registry.get<char>(dst), 'c');
+}
+
+TYPED_TEST(EntityCopy, CrossRegistry) {
+    using namespace entt::literals;
+
+    entt::basic_registry<entt::entity> src{};
+    // other registry type, see typed test suite
+    typename TestFixture::type dst{};
+
+    const auto entity = src.create();
+    const auto copy = dst.create();
+
+    src.emplace<int>(entity, 2);
+    src.emplace<char>(entity, 'c');
+
+    ASSERT_EQ(src.storage<entt::entity>().size(), 1u);
+    ASSERT_EQ(dst.template storage<typename TestFixture::type::entity_type>().size(), 1u);
+
+    ASSERT_TRUE((src.all_of<int, char>(entity)));
+    ASSERT_FALSE((dst.template all_of<int, char>(copy)));
+
+    for(auto [id, storage]: src.storage()) {
+        if(storage.contains(entity)) {
+            auto *other = dst.storage(id);
+
+            if(!other) {
+                using namespace entt::literals;
+                entt::resolve(storage.type()).invoke("storage"_hs, {}, entt::forward_as_meta(dst), id);
+                other = dst.storage(id);
+            }
+
+            other->push(copy, storage.value(entity));
+        }
+    }
+
+    ASSERT_EQ(src.storage<entt::entity>().size(), 1u);
+    ASSERT_EQ(dst.template storage<typename TestFixture::type::entity_type>().size(), 1u);
+
+    ASSERT_TRUE((src.all_of<int, char>(entity)));
+    ASSERT_TRUE((dst.template all_of<int, char>(copy)));
+    ASSERT_EQ(dst.template get<int>(copy), 2);
+    ASSERT_EQ(dst.template get<char>(copy), 'c');
+}