Add 'contrib/catch2/' from commit 'bc524d70253a4ab2fe40c3ca3e5666e267c0a4d1'

git-subtree-dir: contrib/catch2
git-subtree-mainline: a8b0ea58e60bb0326b7f7c8f3c736d89ce9ef1df
git-subtree-split: bc524d70253a4ab2fe40c3ca3e5666e267c0a4d1

1 files changed, 173 insertions, 0 deletions

diff --git a/contrib/catch2/tests/SelfTest/UsageTests/Benchmark.tests.cpp b/contrib/catch2/tests/SelfTest/UsageTests/Benchmark.tests.cpp
new file mode 100644
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+++ b/contrib/catch2/tests/SelfTest/UsageTests/Benchmark.tests.cpp
@@ -0,0 +1,173 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+// Adapted from donated nonius code.
+
+#include <catch2/catch_test_macros.hpp>
+#include <catch2/benchmark/catch_benchmark.hpp>
+#include <catch2/benchmark/catch_constructor.hpp>
+#include <catch2/generators/catch_generators_range.hpp>
+
+#include <map>
+
+namespace {
+    std::uint64_t Fibonacci(std::uint64_t number) {
+        return number < 2 ? number : Fibonacci(number - 1) + Fibonacci(number - 2);
+    }
+}
+
+TEST_CASE("Benchmark Fibonacci", "[!benchmark]") {
+    CHECK(Fibonacci(0) == 0);
+    // some more asserts..
+    CHECK(Fibonacci(5) == 5);
+    // some more asserts..
+
+    REQUIRE( Fibonacci( 20 ) == 6'765 );
+    BENCHMARK( "Fibonacci 20" ) {
+        return Fibonacci(20);
+    };
+
+    REQUIRE( Fibonacci( 25 ) == 75'025 );
+    BENCHMARK( "Fibonacci 25" ) {
+        return Fibonacci(25);
+    };
+
+    BENCHMARK("Fibonacci 30") {
+        return Fibonacci(30);
+    };
+
+    BENCHMARK("Fibonacci 35") {
+        return Fibonacci(35);
+    };
+}
+
+TEST_CASE("Benchmark containers", "[!benchmark]") {
+    static const int size = 100;
+
+    std::vector<int> v;
+    std::map<int, int> m;
+
+    SECTION("without generator") {
+        BENCHMARK("Load up a vector") {
+            v = std::vector<int>();
+            for (int i = 0; i < size; ++i)
+                v.push_back(i);
+        };
+        REQUIRE(v.size() == size);
+
+        // test optimizer control
+        BENCHMARK("Add up a vector's content") {
+            uint64_t add = 0;
+            for (int i = 0; i < size; ++i)
+                add += v[i];
+            return add;
+        };
+
+        BENCHMARK("Load up a map") {
+            m = std::map<int, int>();
+            for (int i = 0; i < size; ++i)
+                m.insert({ i, i + 1 });
+        };
+        REQUIRE(m.size() == size);
+
+        BENCHMARK("Reserved vector") {
+            v = std::vector<int>();
+            v.reserve(size);
+            for (int i = 0; i < size; ++i)
+                v.push_back(i);
+        };
+        REQUIRE(v.size() == size);
+
+        BENCHMARK("Resized vector") {
+            v = std::vector<int>();
+            v.resize(size);
+            for (int i = 0; i < size; ++i)
+                v[i] = i;
+        };
+        REQUIRE(v.size() == size);
+
+        int array[size] {};
+        BENCHMARK("A fixed size array that should require no allocations") {
+            for (int i = 0; i < size; ++i)
+                array[i] = i;
+        };
+        int sum = 0;
+        for (int val : array)
+            sum += val;
+        REQUIRE(sum > size);
+
+        SECTION("XYZ") {
+
+            BENCHMARK_ADVANCED("Load up vector with chronometer")(Catch::Benchmark::Chronometer meter) {
+                std::vector<int> k;
+                meter.measure([&](int idx) {
+                    k = std::vector<int>();
+                    for (int i = 0; i < size; ++i)
+                        k.push_back(idx);
+                });
+                REQUIRE(k.size() == size);
+            };
+
+            int runs = 0;
+            BENCHMARK("Fill vector indexed", benchmarkIndex) {
+                v = std::vector<int>();
+                v.resize(size);
+                for (int i = 0; i < size; ++i)
+                    v[i] = benchmarkIndex;
+                runs = benchmarkIndex;
+            };
+
+            for (int val : v) {
+                REQUIRE(val == runs);
+            }
+        }
+    }
+
+    SECTION("with generator") {
+        auto generated = GENERATE(range(0, 10));
+        BENCHMARK("Fill vector generated") {
+            v = std::vector<int>();
+            v.resize(size);
+            for (int i = 0; i < size; ++i)
+                v[i] = generated;
+        };
+        for (int val : v) {
+            REQUIRE(val == generated);
+        }
+    }
+
+    SECTION("construct and destroy example") {
+        BENCHMARK_ADVANCED("construct")(Catch::Benchmark::Chronometer meter) {
+            std::vector<Catch::Benchmark::storage_for<std::string>> storage(meter.runs());
+            meter.measure([&](int i) { storage[i].construct("thing"); });
+        };
+
+        BENCHMARK_ADVANCED("destroy")(Catch::Benchmark::Chronometer meter) {
+            std::vector<Catch::Benchmark::destructable_object<std::string>> storage(meter.runs());
+            for(auto&& o : storage)
+                o.construct("thing");
+            meter.measure([&](int i) { storage[i].destruct(); });
+        };
+    }
+}
+
+TEST_CASE("Skip benchmark macros", "[!benchmark]") {
+    std::vector<int> v;
+    BENCHMARK("fill vector") {
+        v.emplace_back(1);
+        v.emplace_back(2);
+        v.emplace_back(3);
+    };
+    REQUIRE(v.size() == 0);
+
+    std::size_t counter{0};
+    BENCHMARK_ADVANCED("construct vector")(Catch::Benchmark::Chronometer meter) {
+        std::vector<Catch::Benchmark::storage_for<std::string>> storage(meter.runs());
+        meter.measure([&](int i) { storage[i].construct("thing"); counter++; });
+    };
+    REQUIRE(counter == 0);
+}