WIP: tests + bug fixing

test/ident.cpp

@@ -0,0 +1,26 @@
+#include <gtest/gtest.h>
+#include <ident.hpp>
+
+struct A {};
+struct B {};
+
+TEST(Identifier, Uniqueness) {
+    constexpr auto ID = entt::ident<A, B>;
+    constexpr A a;
+    constexpr B b;
+
+    ASSERT_NE(ID.get<A>(), ID.get<B>());
+    ASSERT_EQ(ID.get<A>(), ID.get<decltype(a)>());
+    ASSERT_NE(ID.get<A>(), ID.get<decltype(b)>());
+    ASSERT_EQ(ID.get<A>(), ID.get<A>());
+    ASSERT_EQ(ID.get<B>(), ID.get<B>());
+
+    // test uses in constant expressions
+    switch(ID.get<B>()) {
+    case ID.get<A>():
+        FAIL();
+        break;
+    case ID.get<B>():
+        SUCCEED();
+    }
+}