From bf5c17c106cbd255a91b5a94e2486626e55d2a91 Mon Sep 17 00:00:00 2001
From: BlackMATov <blackmatov@gmail.com>
Date: Mon, 10 Dec 2018 13:10:39 +0700
Subject: [PATCH] copy ctors, comparison operators, swap, hash

---
 promise.hpp | 67 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 tests.cpp   | 46 ++++++++++++++++++++++++++++++++++++
 2 files changed, 113 insertions(+)

diff --git a/promise.hpp b/promise.hpp
index f8d4497..ad1875d 100644
--- a/promise.hpp
+++ b/promise.hpp
@@ -380,6 +380,29 @@ namespace promise_hpp
         promise()
         : state_(std::make_shared<state>()) {}
 
+        promise(const promise&) noexcept = default;
+        promise& operator=(const promise&) noexcept = default;
+
+        void swap(promise& other) noexcept {
+            state_.swap(other.state_);
+        }
+
+        std::size_t hash() const noexcept {
+            return std::hash<state*>()(state_.get());
+        }
+
+        friend bool operator<(const promise& l, const promise& r) noexcept {
+            return l.state_ < r.state_;
+        }
+
+        friend bool operator==(const promise& l, const promise& r) noexcept {
+            return l.state_ == r.state_;
+        }
+
+        friend bool operator!=(const promise& l, const promise& r) noexcept {
+            return l.state_ != r.state_;
+        }
+
         template < typename ResolveF
                  , typename ResolveFR = invoke_hpp::invoke_result_t<ResolveF,T> >
         std::enable_if_t<
@@ -686,6 +709,29 @@ namespace promise_hpp
         promise()
         : state_(std::make_shared<state>()) {}
 
+        promise(const promise&) noexcept = default;
+        promise& operator=(const promise&) noexcept = default;
+
+        void swap(promise& other) noexcept {
+            state_.swap(other.state_);
+        }
+
+        std::size_t hash() const noexcept {
+            return std::hash<state*>()(state_.get());
+        }
+
+        friend bool operator<(const promise& l, const promise& r) noexcept {
+            return l.state_ < r.state_;
+        }
+
+        friend bool operator==(const promise& l, const promise& r) noexcept {
+            return l.state_ == r.state_;
+        }
+
+        friend bool operator!=(const promise& l, const promise& r) noexcept {
+            return l.state_ != r.state_;
+        }
+
         template < typename ResolveF
                  , typename ResolveFR = invoke_hpp::invoke_result_t<ResolveF> >
         std::enable_if_t<
@@ -961,6 +1007,15 @@ namespace promise_hpp
         };
     };
 
+    //
+    // swap
+    //
+
+    template < typename T >
+    void swap(promise<T>& l, promise<T>& r) noexcept {
+        l.swap(r);
+    }
+
     //
     // make_promise
     //
@@ -1107,3 +1162,15 @@ namespace promise_hpp
             std::end(container));
     }
 }
+
+namespace std
+{
+    template < typename T >
+    struct hash<promise_hpp::promise<T>>
+        : std::unary_function<promise_hpp::promise<T>, std::size_t>
+    {
+        std::size_t operator()(const promise_hpp::promise<T>& p) const noexcept {
+            return p.hash();
+        }
+    };
+}
diff --git a/tests.cpp b/tests.cpp
index 5842dcf..6ef753f 100644
--- a/tests.cpp
+++ b/tests.cpp
@@ -104,6 +104,52 @@ TEST_CASE("is_promise_r") {
 }
 
 TEST_CASE("promise") {
+    SECTION("basic") {
+        {
+            auto p1 = pr::promise<int>();
+            auto p2 = pr::promise<int>();
+            REQUIRE_FALSE(p1 == p2);
+            REQUIRE(p1 != p2);
+
+            REQUIRE((p1 < p2 || p2 < p1));
+            REQUIRE(p1.hash() != p2.hash());
+            REQUIRE(p1.hash() == std::hash<pr::promise<int>>()(p1));
+        }
+        {
+            auto p1 = pr::promise<void>();
+            auto p2 = pr::promise<void>();
+            REQUIRE_FALSE(p1 == p2);
+            REQUIRE(p1 != p2);
+
+            REQUIRE((p1 < p2 || p2 < p1));
+            REQUIRE(p1.hash() != p2.hash());
+            REQUIRE(p1.hash() == std::hash<pr::promise<void>>()(p1));
+        }
+        {
+            auto p1 = pr::promise<int>();
+            auto p2 = pr::promise<int>();
+            auto p3 = p1;
+            REQUIRE(p1 == p3);
+            p3 = p2;
+            REQUIRE(p2 == p3);
+        }
+        {
+            auto p1 = pr::promise<int>();
+            auto p2 = pr::promise<int>();
+            auto p3 = p1;
+            p1.swap(p2);
+            REQUIRE(p2 == p3);
+            REQUIRE_FALSE(p1 == p3);
+        }
+        {
+            auto p1 = pr::promise<void>();
+            auto p2 = pr::promise<void>();
+            auto p3 = p1;
+            p1.swap(p2);
+            REQUIRE(p2 == p3);
+            REQUIRE_FALSE(p1 == p3);
+        }
+    }
     SECTION("resolved") {
         {
             int check_42_int = 0;