entity: add visit_tuple

1 files changed, 24 insertions, 4 deletions

diff --git a/test/entity.cpp b/test/entity.cpp
index 80032b6f..21783e24 100644
--- a/test/entity.cpp
+++ b/test/entity.cpp
@@ -1,13 +1,14 @@
 #include "app.hpp"
 #include "compat/assert.hpp"
 #include "src/entity.hpp"
+#include <tuple>
 
 using namespace floormat;
 using namespace floormat::entities;
 
 struct TestAccessors {
-    int bar() const { return _bar; }
-    void set_bar(int value) { _bar = value; }
+    constexpr int bar() const { return _bar; }
+    constexpr void set_bar(int value) { _bar = value; }
     int foo;
     int _bar;
     int _baz;
@@ -22,7 +23,7 @@ static constexpr auto m_baz = entity::type<int>::field("baz"_s, r_baz, w_baz);
 
 namespace floormat {
 
-static void test_accessors()
+static constexpr bool test_accessors()
 {
     auto x = TestAccessors{111, 222, 333};
 
@@ -38,11 +39,30 @@ static void test_accessors()
         auto a = m_foo.read(x), b = m_bar.read(x), c = m_baz.read(x);
         fm_assert(a == 1111 && b == 2222 && c == 3333);
     }
+    return true;
+}
+
+static constexpr bool test_visitor()
+{
+    {
+        int ret = 0;
+        visit_tuple([&](auto x) { ret += x; },
+                    std::tuple<int, short, char, long>{ 1, 2, 3, 4 });
+        fm_assert(ret == 1 + 2 + 3 + 4);
+    }
+    {
+        int ret = 0;
+        visit_tuple([&] { ret++; }, std::tuple<>{});
+        fm_assert(ret == 0);
+    }
+
+    return true;
 }
 
 void test_app::test_entity()
 {
-    test_accessors();
+    static_assert(test_accessors());
+    static_assert(test_visitor());
 }
 
 } // namespace floormat