From a6c4419da6f559cace4a0ee8a363f5f341cc9873 Mon Sep 17 00:00:00 2001
From: PJB3005 <pieterjan.briers+git@gmail.com>
Date: Sat, 25 Jul 2026 15:26:15 +0200
Subject: [PATCH] cast.hpp helper

I was tired of manually bounds-checking my integer casts.
---
 files.cmake              |  1 +
 include/helpers/cast.hpp | 48 ++++++++++++++++++++++++++++++++++++++++
 src/helpers/cast.cpp     | 14 ++++++++++++
 3 files changed, 63 insertions(+)
 create mode 100644 include/helpers/cast.hpp
 create mode 100644 src/helpers/cast.cpp

diff --git a/files.cmake b/files.cmake
index c8c92c9b75..51b2bdf95e 100644
--- a/files.cmake
+++ b/files.cmake
@@ -1581,6 +1581,7 @@ set(DUSK_FILES
         src/helpers/endian.cpp
         src/helpers/offset_ptr.cpp
         src/helpers/string.cpp
+        src/helpers/cast.cpp
 )
 
 set(DUSK_HTTP_BACKEND_FILES
diff --git a/include/helpers/cast.hpp b/include/helpers/cast.hpp
new file mode 100644
index 0000000000..206bc1e3f3
--- /dev/null
+++ b/include/helpers/cast.hpp
@@ -0,0 +1,48 @@
+#pragma once
+
+#include <limits>
+#include <utility>
+#include <span>
+
+/**
+ * Helper functions for performing casts.
+ */
+namespace dusk::helpers::cast {
+    /**
+     * Implementation details of dusk::helpers::cast.
+     */
+    namespace _impl {
+        [[noreturn]] void overrun_high();
+        [[noreturn]] void overrun_low();
+    }
+
+    template <typename T>
+    concept IntCastable = std::is_integral_v<T> && std::is_trivially_copyable_v<T>;
+
+    /**
+     * Helper type that allows easily casting between integer types,
+     * that safely aborts if an overflow were to occur.
+     * Usage:
+     * @code
+     * size_t foobar = 20;
+     * int real = bounded_cast(foobar);
+     * @endcode
+     */
+    template <IntCastable Source>
+    struct bounded_cast {
+        Source src;
+
+        template <IntCastable Target>
+        [[nodiscard]] constexpr operator Target() const {
+            if (std::cmp_greater(src, std::numeric_limits<Target>::max())) [[unlikely]] {
+                _impl::overrun_high();
+            }
+
+            if (std::cmp_less(src, std::numeric_limits<Target>::min())) [[unlikely]] {
+                _impl::overrun_low();
+            }
+
+            return static_cast<Target>(src);
+        }
+    };
+}
diff --git a/src/helpers/cast.cpp b/src/helpers/cast.cpp
new file mode 100644
index 0000000000..71eb3160de
--- /dev/null
+++ b/src/helpers/cast.cpp
@@ -0,0 +1,14 @@
+#include "helpers/cast.hpp"
+#include "global.h"
+
+namespace dusk::helpers::cast::_impl {
+
+void overrun_high() {
+    CRASH("bounded cast overran!");
+}
+
+void overrun_low() {
+    CRASH("bounded cast overran!");
+}
+
+}  // namespace dusk::helpers::cast::_impl