From 55055a23dc476f6eed03c81f46ef8e109782cf6e Mon Sep 17 00:00:00 2001
From: BlackMATov <blackmat@mail.ru>
Date: Fri, 18 Dec 2020 21:35:42 +0700
Subject: [PATCH] add bitfields swap and hash

---
 headers/enum.hpp/enum_bitflags.hpp | 22 ++++++++++++++++++++++
 untests/enum_bitflags_tests.cpp    | 24 ++++++++++++++++++++++++
 2 files changed, 46 insertions(+)

diff --git a/headers/enum.hpp/enum_bitflags.hpp b/headers/enum.hpp/enum_bitflags.hpp
index df2ac34..4d69b17 100644
--- a/headers/enum.hpp/enum_bitflags.hpp
+++ b/headers/enum.hpp/enum_bitflags.hpp
@@ -6,7 +6,9 @@
 
 #pragma once
 
+#include <functional>
 #include <type_traits>
+#include <utility>
 
 namespace enum_hpp::bitflags
 {
@@ -21,6 +23,11 @@ namespace enum_hpp::bitflags
         bitflags(const bitflags&) = default;
         bitflags& operator=(const bitflags&) = default;
 
+        constexpr void swap(bitflags& other) noexcept {
+            using std::swap;
+            swap(flags_, other.flags_);
+        }
+
         constexpr bitflags(enum_type flags)
         : flags_(static_cast<underlying_type>(flags)) {}
 
@@ -60,6 +67,21 @@ namespace enum_hpp::bitflags
     private:
         underlying_type flags_{};
     };
+
+    template < typename Enum >
+    constexpr void swap(bitflags<Enum>& l, bitflags<Enum>& r) noexcept {
+        l.swap(r);
+    }
+}
+
+namespace std
+{
+    template < typename Enum >
+    struct hash<enum_hpp::bitflags::bitflags<Enum>> {
+        size_t operator()(enum_hpp::bitflags::bitflags<Enum> bf) const noexcept {
+            return hash<Enum>{}(bf.as_enum());
+        }
+    };
 }
 
 namespace enum_hpp::bitflags
diff --git a/untests/enum_bitflags_tests.cpp b/untests/enum_bitflags_tests.cpp
index ab96d14..0316a9f 100644
--- a/untests/enum_bitflags_tests.cpp
+++ b/untests/enum_bitflags_tests.cpp
@@ -60,6 +60,30 @@ TEST_CASE("enum_bitflags") {
         }
     }
 
+    SUBCASE("swap") {
+        {
+            bf::bitflags f = access::read | access::write;
+            bf::bitflags g = access::write | access::execute;
+            f.swap(g);
+            CHECK(f == (access::write | access::execute));
+            CHECK(g == (access::read | access::write));
+        }
+        {
+            bf::bitflags f = access::read | access::write;
+            bf::bitflags g = access::write | access::execute;
+            swap(f, g);
+            CHECK(f == (access::write | access::execute));
+            CHECK(g == (access::read | access::write));
+        }
+    }
+
+    SUBCASE("hash") {
+        std::hash<bf::bitflags<access>> hasher1;
+        std::hash<bf::bitflags<access>> hasher2;
+        CHECK(hasher1(access::read) == hasher2(access::read));
+        CHECK(hasher1(access::read) != hasher2(access::read_write));
+    }
+
     SUBCASE("enum_operators") {
         STATIC_CHECK((~access::read) == bf::bitflags<access>(0xFE));
         STATIC_CHECK((access::read | access::write) == bf::bitflags<access>(0x3));