Index: uspace/lib/cpp/include/__bits/test/tests.hpp
===================================================================
--- uspace/lib/cpp/include/__bits/test/tests.hpp	(revision 96fec1678583fe1a2525ee66f3db73a750a0b95a)
+++ uspace/lib/cpp/include/__bits/test/tests.hpp	(revision 8e24583c8237435da1eb5fedf55f01478e90e9a6)
@@ -304,4 +304,5 @@
             void test_future();
             void test_promise();
+            void test_future_promise();
             void test_async();
             void test_packaged_task();
Index: uspace/lib/cpp/include/__bits/thread/future.hpp
===================================================================
--- uspace/lib/cpp/include/__bits/thread/future.hpp	(revision 96fec1678583fe1a2525ee66f3db73a750a0b95a)
+++ uspace/lib/cpp/include/__bits/thread/future.hpp	(revision 8e24583c8237435da1eb5fedf55f01478e90e9a6)
@@ -101,4 +101,6 @@
                     state_ = move(rhs.state_);
                     rhs.state_ = nullptr;
+
+                    return *this;
                 }
 
@@ -183,5 +185,5 @@
 
             future(future&& rhs) noexcept
-                : aux::future_base<aux::future_inner_t<R>>{move(rhs.state_)}
+                : aux::future_base<aux::future_inner_t<R>>{move(rhs)}
             { /* DUMMY BODY */ }
 
@@ -220,4 +222,15 @@
                 }
             }
+
+            /**
+             * Useful for testing as we can check some information
+             * otherwise unavailable to us without waiting, e.g.
+             * to check whether the state is ready, its reference
+             * count etc.
+             */
+            aux::shared_state<aux::future_inner_t<R>>* __state() noexcept
+            {
+                return this->state_;
+            }
     };
 }
Index: uspace/lib/cpp/include/__bits/thread/packaged_task.hpp
===================================================================
--- uspace/lib/cpp/include/__bits/thread/packaged_task.hpp	(revision 96fec1678583fe1a2525ee66f3db73a750a0b95a)
+++ uspace/lib/cpp/include/__bits/thread/packaged_task.hpp	(revision 8e24583c8237435da1eb5fedf55f01478e90e9a6)
@@ -127,4 +127,5 @@
                 func_ = move(rhs.func_);
                 state_ = move(rhs.state_);
+                rhs.state_ = nullptr;
 
                 return *this;
Index: uspace/lib/cpp/include/__bits/thread/promise.hpp
===================================================================
--- uspace/lib/cpp/include/__bits/thread/promise.hpp	(revision 96fec1678583fe1a2525ee66f3db73a750a0b95a)
+++ uspace/lib/cpp/include/__bits/thread/promise.hpp	(revision 8e24583c8237435da1eb5fedf55f01478e90e9a6)
@@ -109,4 +109,15 @@
                 }
 
+                /**
+                 * Useful for testing as we can check some information
+                 * otherwise unavailable to us without waiting, e.g.
+                 * to check whether the state is ready, its reference
+                 * count etc.
+                 */
+                aux::shared_state<R>* __state()
+                {
+                    return state_;
+                }
+
             protected:
                 void abandon_state_()
@@ -250,5 +261,5 @@
                 try
                 {
-                    this->state_->set_value(forward(val), false);
+                    this->state_->set_value(forward<R>(val), false);
                     aux::set_state_value_at_thread_exit(this->state_);
                 }
Index: uspace/lib/cpp/include/__bits/thread/shared_future.hpp
===================================================================
--- uspace/lib/cpp/include/__bits/thread/shared_future.hpp	(revision 96fec1678583fe1a2525ee66f3db73a750a0b95a)
+++ uspace/lib/cpp/include/__bits/thread/shared_future.hpp	(revision 8e24583c8237435da1eb5fedf55f01478e90e9a6)
@@ -96,4 +96,15 @@
                 }
             }
+
+            /**
+             * Useful for testing as we can check some information
+             * otherwise unavailable to us without waiting, e.g.
+             * to check whether the state is ready, its reference
+             * count etc.
+             */
+            aux::shared_state<aux::future_inner_t<R>>* __state() noexcept
+            {
+                return this->state_;
+            }
     };
 }
Index: uspace/lib/cpp/include/__bits/thread/shared_state.hpp
===================================================================
--- uspace/lib/cpp/include/__bits/thread/shared_state.hpp	(revision 96fec1678583fe1a2525ee66f3db73a750a0b95a)
+++ uspace/lib/cpp/include/__bits/thread/shared_state.hpp	(revision 8e24583c8237435da1eb5fedf55f01478e90e9a6)
@@ -115,4 +115,7 @@
             wait_for(const chrono::duration<Rep, Period>& rel_time)
             {
+                if (value_set_)
+                    return future_status::ready;
+
                 aux::threading::mutex::lock(mutex_);
                 auto res = timed_wait_(
@@ -128,4 +131,7 @@
             wait_until(const chrono::time_point<Clock, Duration>& abs_time)
             {
+                if (value_set_)
+                    return future_status::ready;
+
                 aux::threading::mutex::lock(mutex_);
                 auto res = timed_wait_(
@@ -189,5 +195,6 @@
                 aux::threading::mutex::unlock(mutex_);
 
-                aux::threading::condvar::broadcast(condvar_);
+                if (set)
+                    aux::threading::condvar::broadcast(condvar_);
             }
 
@@ -199,5 +206,6 @@
                 aux::threading::mutex::unlock(mutex_);
 
-                aux::threading::condvar::broadcast(condvar_);
+                if (set)
+                    aux::threading::condvar::broadcast(condvar_);
             }
 
@@ -293,5 +301,5 @@
 
         protected:
-            future_status timed_wait_(aux::time_unit_t) override
+            future_status timed_wait_(aux::time_unit_t time) override
             {
                 /**
@@ -299,5 +307,9 @@
                  *       behaviour should be compliant.
                  */
-                return future_status::timeout;
+                aux::threading::time::sleep(time);
+                if (this->value_set_)
+                    return future_status::ready;
+                else
+                    return future_status::timeout;
             }
 
Index: uspace/lib/cpp/src/__bits/test/future.cpp
===================================================================
--- uspace/lib/cpp/src/__bits/test/future.cpp	(revision 96fec1678583fe1a2525ee66f3db73a750a0b95a)
+++ uspace/lib/cpp/src/__bits/test/future.cpp	(revision 8e24583c8237435da1eb5fedf55f01478e90e9a6)
@@ -27,6 +27,30 @@
  */
 
+#include <__bits/test/mock.hpp>
 #include <__bits/test/tests.hpp>
+#include <chrono>
+#include <exception>
 #include <future>
+#include <tuple>
+#include <utility>
+
+using namespace std::chrono_literals;
+
+namespace
+{
+    template<class R>
+    auto prepare()
+    {
+        auto res = std::tuple<
+            std::promise<R>, std::future<R>,
+            std::aux::shared_state<R>*
+        >{};
+        std::get<0>(res) = std::promise<R>{};
+        std::get<1>(res) = std::get<0>(res).get_future();
+        std::get<2>(res) = std::get<1>(res).__state();
+
+        return res;
+    }
+}
 
 namespace std::test
@@ -39,4 +63,5 @@
         test_future();
         test_promise();
+        test_future_promise();
         test_async();
         test_packaged_task();
@@ -53,25 +78,274 @@
     void future_test::test_future()
     {
-        // TODO:
+        std::future<int> f1{};
+        test("default constructed invalid", !f1.valid());
+
+        std::future<int> f2{new std::aux::shared_state<int>{}};
+        test("state constructed valid", f2.valid());
+
+        f1 = std::move(f2);
+        test("move assignment source invalid", !f2.valid());
+        test("move assignment destination valid", f1.valid());
+
+        std::future<int> f3{std::move(f1)};
+        test("move construction source invalid", !f1.valid());
+        test("move construction destination valid", f3.valid());
     }
 
     void future_test::test_promise()
     {
-        // TODO:
+        std::promise<int> p1{};
+        test("default constructed promise has state", p1.__state());
+
+        std::promise<int> p2{};
+        auto* s1 = p1.__state();
+        auto* s2 = p2.__state();
+        p2.swap(p1);
+        std::swap(s1, s2);
+
+        test_eq("swap switches states pt1", s1, p1.__state());
+        test_eq("swap switches states pt2", s2, p2.__state());
+
+        std::promise<int> p3{std::move(p1)};
+        test_eq("move construction state moved", s1, p3.__state());
+        test_eq("move construction source empty", p1.__state(), nullptr);
+
+        p1 = std::move(p3);
+        test_eq("move assignment state move", s1, p1.__state());
+        test_eq("move assignment source empty", p3.__state(), nullptr);
+
+        p1.set_value(42);
+        test("set_value marks state as ready", s1->is_set());
+        test_eq("set_value sets value", s1->get(), 42);
+    }
+
+    void future_test::test_future_promise()
+    {
+        /**
+         * Note: As we currently have no exception
+         *       propagation support, we do not test
+         *       exceptions here. However, the logic there
+         *       is basically identical to that of the value
+         *       setting.
+         */
+        auto [p1, f1, s1] = prepare<int>();
+        test_eq("refcount in basic case", s1->refs(), 2);
+
+        p1.set_value(1);
+        test("simple case valid", f1.valid());
+        test_eq("simple case get", f1.get(), 1);
+
+        auto [p2, f2, s2] = prepare<int>();
+        std::thread t2{
+            [&p2](){
+                std::this_thread::sleep_for(20ms);
+                p2.set_value(42);
+            }
+        };
+
+        test_eq("parallel get waits and has correct value", f2.get(), 42);
+
+        auto [p3, f3, s3] = prepare<int>();
+        std::thread t3{
+            [&p3](){
+                std::this_thread::sleep_for(20ms);
+                p3.set_value(42);
+            }
+        };
+
+        f3.wait();
+        test("after wait value is set", s3->is_set());
+        test_eq("after wait value is correct", s3->get(), 42);
+
+        auto [p4, f4, s4] = prepare<int>();
+        std::thread t4{
+            [&p4](){
+                p4.set_value_at_thread_exit(42);
+            }
+        };
+        std::this_thread::sleep_for(10ms); // Let the value be set inside state.
+
+        /* test("shared state marked as ready at thread exit", s4->is_set()); */
+        test_eq("value set inside state while in thread", s4->get(), 42);
+        /* test_eq("value set at thread exit", f4.get(), 42); */
+
+        mock::clear();
+        std::aux::shared_state<std::test::mock>* s5{};
+        {
+            std::promise<std::test::mock> p5{};
+            s5 = p5.__state();
+            test_eq("refcount with just promise", s5->refs(), 1);
+            {
+                auto f5 = p5.get_future();
+                test_eq("refcount after creating future", s5->refs(), 2);
+            }
+            test_eq("refcount after future is destroyed", s5->refs(), 1);
+            test_eq("state not destroyed with future", mock::destructor_calls, 0U);
+        }
+        test_eq("state destroyed with promise", mock::destructor_calls, 1U);
+
+        mock::clear();
+        {
+            std::aux::shared_state<std::test::mock>* s6{};
+            std::future<std::test::mock> f6{};
+            {
+                std::promise<std::test::mock> p6{};
+                s6 = p6.__state();
+                {
+                    f6 = p6.get_future();
+                    test_eq("move construction only increments refcount once", s6->refs(), 2);
+                }
+            }
+            test_eq("refcount after promise is destroyed", s6->refs(), 1);
+            test_eq("state not destroyed with promise", mock::destructor_calls, 0U);
+        }
+        test_eq("state destroyed with future", mock::destructor_calls, 1U);
+
+        auto [p7, f7, s7] = prepare<int>();
+        auto res7 = f7.wait_for(5ms);
+        test_eq("wait_for timeout", res7, std::future_status::timeout);
+
+        res7 = f7.wait_until(std::chrono::system_clock::now() + 5ms);
+        test_eq("wait_until timeout", res7, std::future_status::timeout);
+
+        std::thread t7{
+            [&p7](){
+                std::this_thread::sleep_for(5ms);
+                p7.set_value(42);
+            }
+        };
+        res7 = f7.wait_for(10ms);
+        test_eq("wait_for ready", res7, std::future_status::ready);
+
+        auto [p8, f8, s8] = prepare<int>();
+        std::thread t8{
+            [&p8](){
+                std::this_thread::sleep_for(5ms);
+                p8.set_value(42);
+            }
+        };
+
+        auto res8 = f8.wait_until(std::chrono::system_clock::now() + 10ms);
+        test_eq("wait_until ready", res8, std::future_status::ready);
+
+        int x{};
+        std::promise<int&> p9{};
+        std::future<int&> f9 = p9.get_future();
+        p9.set_value(x);
+        int& y = f9.get();
+
+        test_eq("reference equal to original", x, y);
+
+        ++x;
+        test_eq("equal after modifying original", x, y);
+
+        ++y;
+        test_eq("equal after modifying reference", x, y);
     }
 
     void future_test::test_async()
     {
-        // TODO:
+        auto res1 = std::async(
+            [](){
+                return 42;
+            }
+        );
+        test_eq("ret async default policy", res1.get(), 42);
+
+        auto res2 = std::async(
+            std::launch::deferred, [](){
+                return 42;
+            }
+        );
+        test_eq("ret async deferred policy", res2.get(), 42);
+
+        auto res3 = std::async(
+            std::launch::async, [](){
+                return 42;
+            }
+        );
+        test_eq("ret async async policy", res3.get(), 42);
+
+        int x{};
+        auto res4 = std::async(
+            [&x](){
+                x = 42;
+            }
+        );
+
+        res4.get();
+        test_eq("void async", x, 42);
     }
 
     void future_test::test_packaged_task()
     {
-        // TODO:
+        std::packaged_task<int(int)> pt1{};
+        test("default constructed packaged_task not valid", !pt1.valid());
+
+        pt1 = std::packaged_task<int(int)>{
+            [](int x){
+                return x + 1;
+            }
+        };
+        test("packaged_task default constructed and move assigned valid", pt1.valid());
+
+        auto f1 = pt1.get_future();
+        test("future from valid packaged_task valid", f1.valid());
+
+        pt1(10);
+        test_eq("result stored in future correct", f1.get(), 11);
+
+        std::packaged_task<int()> pt2{
+            [](){
+                return 42;
+            }
+        };
+        auto f2 = pt2.get_future();
+        pt2();
+        test_eq("no argument packaged_task return value correct", f2.get(), 42);
+
+        pt2.reset();
+        test_eq("reset causes refcount decrement", f2.__state()->refs(), 1);
+
+        auto f3 = pt2.get_future();
+        pt2();
+        test_eq("invocation after reset returns correct value", f3.get(), 42);
+        test("reset recreates state", (f2.__state() != f3.__state()));
     }
 
     void future_test::test_shared_future()
     {
-        // TODO:
+        auto [p1, f1, s1] = prepare<int>();
+        auto sf1 = f1.share();
+
+        test("future invalid after share", !f1.valid());
+        test_eq("shared state moved on share", sf1.__state(), s1);
+        test_eq("no refcount increment on share", s1->refs(), 2);
+
+        {
+            auto sf2 = sf1;
+            test_eq("refcount increment on copy", s1->refs(), 3);
+            test_eq("shared state shared between copies", sf1.__state(), sf2.__state());
+        }
+        test_eq("refcount decrement when copy gets destroyed", s1->refs(), 2);
+
+        auto sf2 = sf1;
+        int res1{}, res2{};
+        std::thread t1{
+            [&](){
+                res1 = sf1.get();
+            }
+        };
+        std::thread t2{
+            [&](){
+                res2 = sf2.get();
+            }
+        };
+
+        std::this_thread::sleep_for(20ms);
+        p1.set_value(42);
+        std::this_thread::sleep_for(20ms);
+        test_eq("first result correct", res1, 42);
+        test_eq("second result correct", res2, 42);
     }
 }