Add metrics::running_time

include/cpp-sort/fwd.h

@@ -8,6 +8,7 @@
 ////////////////////////////////////////////////////////////
 // Headers
 ////////////////////////////////////////////////////////////
+#include <chrono>
 #include <cstddef>
 
 namespace cppsort
@@ -109,6 +110,11 @@ namespace cppsort
         struct comparisons;
         template<typename Sorter, typename CountType=std::size_t>
         struct projections;
+        template<
+            typename Sorter,
+            typename DurationType = typename std::chrono::steady_clock::duration
+        >
+        struct running_time;
     }
 }
 

include/cpp-sort/metrics/running_time.h

@@ -0,0 +1,72 @@
+/*
+ * Copyright (c) 2023 Morwenn
+ * SPDX-License-Identifier: MIT
+ */
+#ifndef CPPSORT_METRICS_RUNNING_TIME_H_
+#define CPPSORT_METRICS_RUNNING_TIME_H_
+
+////////////////////////////////////////////////////////////
+// Headers
+////////////////////////////////////////////////////////////
+#include <chrono>
+#include <utility>
+#include <cpp-sort/fwd.h>
+#include <cpp-sort/utility/adapter_storage.h>
+#include <cpp-sort/utility/metrics_tools.h>
+#include "../detail/checkers.h"
+#include "../detail/type_traits.h"
+
+namespace cppsort
+{
+namespace metrics
+{
+    ////////////////////////////////////////////////////////////
+    // Tag
+
+    struct running_time_tag {};
+
+    ////////////////////////////////////////////////////////////
+    // Metric
+
+    template<typename Sorter, typename DurationType>
+    struct running_time:
+        utility::adapter_storage<Sorter>,
+        cppsort::detail::check_iterator_category<Sorter>,
+        cppsort::detail::check_is_always_stable<Sorter>
+    {
+        using tag_t = running_time_tag;
+        using metric_t = utility::metric<DurationType, tag_t>;
+
+        running_time() = default;
+
+        constexpr explicit running_time(Sorter sorter):
+            utility::adapter_storage<Sorter>(std::move(sorter))
+        {}
+
+        template<typename... Args>
+        auto operator()(Args&&... args) const
+            -> decltype(
+                this->get()(std::forward<Args>(args)...),
+                metric_t(std::declval<DurationType>())
+            )
+        {
+            auto start = std::chrono::steady_clock::now();
+            this->get()(std::forward<Args>(args)...);
+            auto stop = std::chrono::steady_clock::now();
+            return metric_t(std::chrono::duration_cast<DurationType>(stop - start));
+        }
+    };
+}}
+
+namespace cppsort
+{
+    ////////////////////////////////////////////////////////////
+    // is_stable specialization
+
+    template<typename Sorter, typename DurationType, typename... Args>
+    struct is_stable<metrics::running_time<Sorter, DurationType>(Args...)>:
+        is_stable<Sorter(Args...)>
+    {};
+}
+
+#endif // CPPSORT_METRICS_RUNNING_TIME_H_

tests/CMakeLists.txt

@@ -155,6 +155,7 @@ add_executable(main-tests
     # Metrics tests
     metrics/comparisons.cpp
     metrics/projections.cpp
+    metrics/running_time.cpp
 
     # Comparators tests
     comparators/case_insensitive_less.cpp

tests/metrics/running_time.cpp

@@ -0,0 +1,46 @@
+/*
+ * Copyright (c) 2023 Morwenn
+ * SPDX-License-Identifier: MIT
+ */
+#include <algorithm>
+#include <chrono>
+#include <iterator>
+#include <list>
+#include <catch2/catch_test_macros.hpp>
+#include <cpp-sort/metrics/running_time.h>
+#include <cpp-sort/sorters/splay_sorter.h>
+#include <testing-tools/distributions.h>
+
+TEST_CASE( "basic metrics::running_time tests", "[metrics]" )
+{
+    using namespace std::chrono_literals;
+
+    std::list<int> collection;
+    auto distribution = dist::shuffled{};
+    distribution(std::back_inserter(collection), 102);
+
+    SECTION( "with default duration type" )
+    {
+        cppsort::metrics::running_time<
+            cppsort::splay_sorter
+        > sorter;
+
+        auto res = sorter(collection);
+        CHECK( res > 0s );
+        CHECK( std::is_sorted(collection.begin(), collection.end()) );
+    }
+
+    SECTION( "with explicit duration type" )
+    {
+        cppsort::metrics::running_time<
+            cppsort::splay_sorter,
+            std::chrono::milliseconds
+        > sorter;
+
+        auto res = sorter(collection);
+        CHECK( res >= 0s );
+        CHECK( res <= 1s );
+        CHECK( std::is_sorted(collection.begin(), collection.end()) );
+    }
+
+}