From ebaaaf5ea74a405b2553f2b17ebed077ef4e4836 Mon Sep 17 00:00:00 2001
From: Yaraslau Tamashevich <yaraslau.tamashevich@gmail.com>
Date: Fri, 21 Jun 2024 19:35:29 +0300
Subject: [PATCH] Add division check for debug mode

---
 CMakeLists.txt              |  3 +++
 include/boxed-cpp/boxed.hpp | 42 +++++++++++++++++++++++++++++++++++--
 test-boxed-cpp.cpp          | 26 +++++++++++++++++++++++
 3 files changed, 69 insertions(+), 2 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index b834525..b6b849a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -20,6 +20,9 @@ target_include_directories(boxed-cpp INTERFACE
     $<BUILD_INTERFACE:${${PROJECT_NAME}_SOURCE_DIR}/include>
     $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>
 )
+if(CMAKE_BUILD_TYPE STREQUAL "Debug")
+    target_compile_definitions(boxed-cpp INTERFACE BOXED_DEBUG)
+endif()
 
 # Generate the version, config and target files
 include(CMakePackageConfigHelpers)
diff --git a/include/boxed-cpp/boxed.hpp b/include/boxed-cpp/boxed.hpp
index 3986c8b..579b5f0 100644
--- a/include/boxed-cpp/boxed.hpp
+++ b/include/boxed-cpp/boxed.hpp
@@ -4,7 +4,11 @@
 #include <compare>
 #include <iostream>
 #include <limits>
+#include <stdexcept>
 #include <type_traits>
+#if defined(BOXED_DEBUG)
+    #include <cassert>
+#endif
 
 namespace boxed
 {
@@ -126,7 +130,41 @@ template <typename T, typename U> constexpr boxed<T, U>& operator/=(boxed<T, U>&
 template <typename T, typename U> constexpr boxed<T, U>& operator%=(boxed<T, U>& a, boxed<T, U> const& b) noexcept { a.value %= b.value; return a; }
 
 template <typename T, typename U> std::ostream& operator<<(std::ostream& os, boxed<T, U> const& v) { return os << v.value; }
-    // clang-format on
+
+// clang-format on
+#if defined(BOXED_DEBUG)
+
+    template <std::integral T, typename U>
+    constexpr boxed<T, U> operator/(boxed<T, U> const& a, boxed<T, U> const& b)
+    {
+        auto div = std::div(b.value, a.value);
+        if (div.rem != 0)
+            throw std::invalid_argument("Division is not exact");
+        return boxed<T, U> { div.quot };
+    }
+
+    template <std::integral T, typename U>
+    constexpr boxed<T, U> operator/(boxed<T, U> const& a, T b)
+    {
+        return a / boxed<T, U> { b };
+    }
+
+    template <std::integral T, typename U>
+    constexpr boxed<T, U> operator/(T b, boxed<T, U> const& a)
+    {
+        return boxed<T, U> { b } / a;
+    }
+
+    template <std::integral T, typename U>
+    constexpr boxed<T, U>& operator/=(boxed<T, U>& a, boxed<T, U> const& b)
+    {
+        auto res = a / b;
+        a = res;
+        return a;
+    }
+
+#endif
+
 } // namespace detail
 
 namespace helper
@@ -216,7 +254,7 @@ namespace fmt
 {
 
 template <typename Type, typename Tag>
-struct fmt::formatter<boxed::detail::boxed<Type, Tag>>
+struct formatter<boxed::detail::boxed<Type, Tag>>
 {
     constexpr auto parse(fmt::format_parse_context& ctx) { return ctx.begin(); }
 
diff --git a/test-boxed-cpp.cpp b/test-boxed-cpp.cpp
index dcf107a..23ea128 100644
--- a/test-boxed-cpp.cpp
+++ b/test-boxed-cpp.cpp
@@ -4,6 +4,7 @@
 #include <cmath>
 #include <functional>
 #include <limits>
+#include <stdexcept>
 #include <type_traits>
 
 #include <boxed-cpp/boxed.hpp>
@@ -215,3 +216,28 @@ TEST_CASE("advanced")
     REQUIRE(x_coord(rho, theta, phi) == x_coord(theta, phi, rho));
     REQUIRE(x_coord(phi, theta, rho) == x_coord(phi, theta, rho));
 }
+
+TEST_CASE("devision of integral_types")
+{
+    using Int = boxed::boxed<int>;
+    int int_a { 10 };
+    Int Int_a { 10 };
+    int int_b { 3 };
+    Int Int_b { 3 };
+#if defined(BOXED_DEBUG)
+    REQUIRE_THROWS_AS(int_a / Int_b, std::invalid_argument);
+    REQUIRE_THROWS_AS(Int_a / int_b, std::invalid_argument);
+    REQUIRE_THROWS_AS(Int_a / Int_b, std::invalid_argument);
+    REQUIRE_THROWS_AS([&](){
+        Int_a /= Int_b;
+    }(), std::invalid_argument);
+
+
+#else
+    REQUIRE(unbox(int_a / Int_b) == 3);
+    REQUIRE(unbox(Int_a / int_b) == 3);
+    REQUIRE(unbox(Int_a / Int_b) == 3);
+    Int_a /= Int_b;
+    REQUIRE(unbox(Int_a) == 3);
+#endif
+}