From a9cefcb823a9ee05dbb836a54ef554bfa949e073 Mon Sep 17 00:00:00 2001
From: Michele Caini <michele.caini@gmail.com>
Date: Tue, 10 Aug 2021 16:07:17 +0200
Subject: [PATCH] meta: avoid risk of name clashing on meta types and meta data
 members

---
 src/entt/meta/factory.hpp    | 15 +++++++++------
 test/entt/meta/meta_data.cpp | 13 +++++++++++++
 test/entt/meta/meta_type.cpp | 13 +++++++++++++
 3 files changed, 35 insertions(+), 6 deletions(-)

diff --git a/src/entt/meta/factory.hpp b/src/entt/meta/factory.hpp
index 20ea504ae..c16ccae06 100644
--- a/src/entt/meta/factory.hpp
+++ b/src/entt/meta/factory.hpp
@@ -159,10 +159,11 @@ struct meta_factory<Type> {
     auto type(const id_type id = type_hash<Type>::value()) {
         auto * const node = internal::meta_info<Type>::resolve();
 
+        meta_range<internal::meta_type_node *, internal::meta_type_node> range{*internal::meta_context::global()};
+        ENTT_ASSERT(std::find_if(range.cbegin(), range.cend(), [id, node](const auto *curr) { return curr != node && curr->id == id; }) == range.cend(), "Duplicate identifier");
         node->id = id;
 
-        if(meta_range<internal::meta_type_node *, internal::meta_type_node> range{*internal::meta_context::global()}; std::find(range.cbegin(), range.cend(), node) == range.cend()) {
-            ENTT_ASSERT(std::find_if(range.cbegin(), range.cend(), [id](const auto *curr) { return curr->id == id; }) == range.cend(), "Duplicate identifier");
+        if(std::find(range.cbegin(), range.cend(), node) == range.cend()) {
             node->next = *internal::meta_context::global();
             *internal::meta_context::global() = node;
         }
@@ -411,10 +412,11 @@ struct meta_factory<Type> {
                 &meta_getter<Type, Data, Policy>
             };
 
+            meta_range<internal::meta_data_node *, internal::meta_data_node> range{type->data};
+            ENTT_ASSERT(std::find_if(range.cbegin(), range.cend(), [id](const auto *curr) { return curr != &node && curr->id == id; }) == range.cend(), "Duplicate identifier");
             node.id = id;
 
-            if(meta_range<internal::meta_data_node *, internal::meta_data_node> range{type->data}; std::find(range.cbegin(), range.cend(), &node) == range.cend()) {
-                ENTT_ASSERT(std::find_if(range.cbegin(), range.cend(), [id](const auto *curr) { return curr->id == id; }) == range.cend(), "Duplicate identifier");
+            if(std::find(range.cbegin(), range.cend(), &node) == range.cend()) {
                 node.next = type->data;
                 type->data = &node;
             }
@@ -460,10 +462,11 @@ struct meta_factory<Type> {
             &meta_getter<Type, Getter, Policy>
         };
 
+        meta_range<internal::meta_data_node *, internal::meta_data_node> range{type->data};
+        ENTT_ASSERT(std::find_if(range.cbegin(), range.cend(), [id](const auto *curr) { return curr != &node && curr->id == id; }) == range.cend(), "Duplicate identifier");
         node.id = id;
 
-        if(meta_range<internal::meta_data_node *, internal::meta_data_node> range{type->data}; std::find(range.cbegin(), range.cend(), &node) == range.cend()) {
-            ENTT_ASSERT(std::find_if(range.cbegin(), range.cend(), [id](const auto *curr) { return curr->id == id; }) == range.cend(), "Duplicate identifier");
+        if(std::find(range.cbegin(), range.cend(), &node) == range.cend()) {
             node.next = type->data;
             type->data = &node;
         }
diff --git a/test/entt/meta/meta_data.cpp b/test/entt/meta/meta_data.cpp
index 52fb09d31..cd92b4389 100644
--- a/test/entt/meta/meta_data.cpp
+++ b/test/entt/meta/meta_data.cpp
@@ -515,3 +515,16 @@ TEST_F(MetaData, ReRegistration) {
     ASSERT_FALSE(type.data("value"_hs));
     ASSERT_TRUE(type.data("field"_hs));
 }
+
+TEST_F(MetaData, NameCollision) {
+    using namespace entt::literals;
+
+    ASSERT_NO_FATAL_FAILURE(entt::meta<clazz_t>().data<&clazz_t::j>("j"_hs));
+    ASSERT_TRUE(entt::resolve<clazz_t>().data("j"_hs));
+
+    ASSERT_NO_FATAL_FAILURE(entt::meta<clazz_t>().data<&clazz_t::j>("cj"_hs));
+    ASSERT_FALSE(entt::resolve<clazz_t>().data("j"_hs));
+    ASSERT_TRUE(entt::resolve<clazz_t>().data("cj"_hs));
+
+    ASSERT_DEATH(entt::meta<clazz_t>().data<&clazz_t::j>("i"_hs), "");
+}
diff --git a/test/entt/meta/meta_type.cpp b/test/entt/meta/meta_type.cpp
index 018be8107..4e7ac0fd7 100644
--- a/test/entt/meta/meta_type.cpp
+++ b/test/entt/meta/meta_type.cpp
@@ -640,3 +640,16 @@ TEST_F(MetaType, ReRegistration) {
     ASSERT_TRUE(entt::resolve("real"_hs));
     ASSERT_TRUE(entt::resolve("real"_hs).data("var"_hs));
 }
+
+TEST_F(MetaType, NameCollision) {
+    using namespace entt::literals;
+
+    ASSERT_NO_FATAL_FAILURE(entt::meta<clazz_t>().type("clazz"_hs));
+    ASSERT_TRUE(entt::resolve("clazz"_hs));
+
+    ASSERT_NO_FATAL_FAILURE(entt::meta<clazz_t>().type("quux"_hs));
+    ASSERT_FALSE(entt::resolve("clazz"_hs));
+    ASSERT_TRUE(entt::resolve("quux"_hs));
+
+    ASSERT_DEATH(entt::meta<clazz_t>().type("abstract"_hs), "");
+}