Release 1.17.1

CMakeLists.txt

@@ -5,7 +5,7 @@ cmake_minimum_required(VERSION 3.8.0)
 
 list(APPEND CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/cmake)
 
-project(cpp-sort VERSION 1.17.0 LANGUAGES CXX)
+project(cpp-sort VERSION 1.17.1 LANGUAGES CXX)
 
 include(CMakePackageConfigHelpers)
 include(GNUInstallDirs)
@@ -24,7 +24,7 @@ if (CPPSORT_USE_LIBASSERT)
     include(DownloadProject)
     download_project(PROJ libassert
                      GIT_REPOSITORY https://github.com/jeremy-rifkin/libassert
-                     GIT_TAG 634f50fb4086d377ad9a2f83d693d2e8fe4972a7  # v2.1.4
+                     GIT_TAG bd33ba116f209bf71761c58dccc2f3bf277e0824  # v2.2.1
                      UPDATE_DISCONNECTED 1
     )
     add_subdirectory(${libassert_SOURCE_DIR} ${libassert_BINARY_DIR})

README.md

@@ -1,10 +1,13 @@
 ![cpp-sort logo](docs/images/cpp-sort-logo.svg)
 
-[![Latest Release](https://img.shields.io/badge/release-1.17.0-blue.svg)](https://github.com/Morwenn/cpp-sort/releases/tag/1.17.0)
-[![Conan Package](https://img.shields.io/badge/conan-cpp--sort%2F1.17.0-blue.svg)](https://conan.io/center/recipes/cpp-sort?version=1.17.0)
+[![Latest Release](https://img.shields.io/badge/release-1.17.1-blue.svg)](https://github.com/Morwenn/cpp-sort/releases/tag/1.17.1)
+[![Conan Package](https://img.shields.io/badge/conan-cpp--sort%2F1.17.1-blue.svg)](https://conan.io/center/recipes/cpp-sort?version=1.17.1)
 [![Code Coverage](https://codecov.io/gh/Morwenn/cpp-sort/branch/develop/graph/badge.svg)](https://codecov.io/gh/Morwenn/cpp-sort)
 [![Pitchfork Layout](https://img.shields.io/badge/standard-PFL-orange.svg)](https://github.com/vector-of-bool/pitchfork)
 
+> [!WARNING]
+> **Branch 1.x.y of this library is now in maintenance-only mode: bug fixes might happen and lead to patch versions, but new development will now exclusively happen in branch 2.x.y, which requires at least C++17.**
+
 > *It would be nice if only one or two of the sorting methods would dominate all of the others,
 > regardless of application or the computer being used. But in fact, each method has its own
 > peculiar virtues. [...] Thus we find that nearly all of the algorithms deserve to be remembered,
@@ -117,9 +120,10 @@ page][benchmarks].
 
 # Compiler support & tooling
 
-![Ubuntu builds status](https://github.com/Morwenn/cpp-sort/workflows/Ubuntu%20Builds/badge.svg?branch=develop)
-![Windows builds status](https://github.com/Morwenn/cpp-sort/workflows/MSVC%20Builds/badge.svg?branch=develop)
-![MacOS builds status](https://github.com/Morwenn/cpp-sort/workflows/MacOS%20Builds/badge.svg?branch=develop)
+![Ubuntu builds status](https://github.com/Morwenn/cpp-sort/actions/workflows/build-ubuntu.yml/badge.svg?branch=1.x.y-develop)
+![MSVC builds status](https://github.com/Morwenn/cpp-sort/actions/workflows/build-msvc.yml/badge.svg?branch=1.x.y-develop)
+![MinGW-w64 builds status](https://github.com/Morwenn/cpp-sort/actions/workflows/build-mingw.yml/badge.svg?branch=1.x.y-develop)
+![MacOS builds status](https://github.com/Morwenn/cpp-sort/actions/workflows/build-macos.yml/badge.svg?branch=1.x.y-develop)
 
 **cpp-sort** requires C++14 support, and should work with the following compilers:
 * g++-9 or more recent.

cmake/DownloadProject.CMakeLists.cmake.in

@@ -1,7 +1,7 @@
 # Distributed under the OSI-approved MIT License.  See accompanying
 # file LICENSE or https://github.com/Crascit/DownloadProject for details.
 
-cmake_minimum_required(VERSION 2.8.2)
+cmake_minimum_required(VERSION 3.5.0)
 
 project(${DL_ARGS_PROJ}-download NONE)
 

conanfile.py

@@ -16,7 +16,7 @@
 
 class CppSortConan(ConanFile):
     name = "cpp-sort"
-    version = "1.17.0"
+    version = "1.17.1"
     description = "Sorting algorithms & related tools"
     license = "MIT"
     url = "https://github.com/Morwenn/cpp-sort"

docs/Home.md

@@ -1,6 +1,6 @@
 ![cpp-sort logo](images/cpp-sort-logo.svg)
 
-Welcome to the **cpp-sort 1.17.0** documentation!
+Welcome to the **cpp-sort 1.17.1** documentation!
 
 This wiki contains documentation about the library: basic documentation about the many sorting tools and how to use them, documentation about the additional utilities provided by the library, as well as a few tutorials about writing your own sorters or sorter adapters. This main page explains a few general things that didn't quite fit in other parts of the documentation.
 

docs/Measures-of-presortedness.md

@@ -235,7 +235,7 @@ Computes the *Oscillation* measure described by C. Levcopoulos and O. Petersson
 
 When there isn't enough extra memory available, `probe::osc` falls back to an in-place O(n²) algorithm.
 
-`max_for_size`: (|*X*| * (|*X*| - 2) - 1) / 2 when the values in *X* are strongly oscillating.
+`max_for_size`: it is reached when the values in $X$ are strongly oscillating, and equals $\frac{|X|(|X| - 2)}{2}$ when $|X|$ is even, and $\frac{|X|(|X| - 2) - 1}{2}$ when $|X|$ is odd.
 
 **Note:** *Osc* does not respect Mannila's criterion 5: $Osc(\langle 2, 4, 1, 3, 1, 3 \rangle) \not \le |\langle 4, 1, 3, 1, 3 \rangle| + Osc(\langle 4, 1, 3, 1, 3 \rangle)$, though it is possible that it only happens when equivalent elements are involved.
 
@@ -303,7 +303,7 @@ Spearman's footrule distance: sum of distances between the position of individua
 #include <cpp-sort/probes/sus.h>
 ```
 
-Computes the minimum number of non-decreasing subsequences (of possibly not adjacent elements) into which *X* can be partitioned. It happens to correspond to the size of the [longest decreasing subsequence][longest-increasing-subsequence] of *X*.
+Computes the minimum number of non-decreasing subsequences (of possibly not adjacent elements) into which *X* can be partitioned, minus 1. It happens to correspond to the size of the [longest decreasing subsequence][longest-increasing-subsequence] of *X* minus 1.
 
 *SUS* stands for *Shuffled Up-Sequences* and was introduced in *Sorting Shuffled Monotone Sequences* by C. Levcopoulos and O. Petersson.
 

docs/Tooling.md

@@ -63,10 +63,10 @@ Note: when `CPPSORT_ENABLE_AUDITS` is `ON`, assertions in the library are enable
 conan search cpp-sort --remote=conancenter
 ```
 
-And then install any version to your local cache as follows (here with version 1.17.0):
+And then install any version to your local cache as follows (here with version 1.17.1):
 
 ```sh
-conan install --requires=cpp-sort/1.17.0
+conan install --requires=cpp-sort/1.17.1
 ```
 
 The packages downloaded from conan-center are minimal and only contain the files required to use **cpp-sort** as a library: the headers, CMake files and licensing information. If you need anything else you have to create your own package with the `conanfile.py` available in this repository.
@@ -78,7 +78,7 @@ The packages downloaded from conan-center are minimal and only contain the files
 [Gollum][gollum], if installed, can be used to browse this documentation offline:
 
 1. Navigate to the main `cpp-sort` directory in the command line
-2. `gollum --page-file-dir docs --ref <branch-name>`
+2. `gollum --page-file-dir docs --ref <branch-name> --math katex`
 3. Visit http://localhost:4567/Home
 
 This can notably used to browse old versions of the documentation. It seems however that `--ref` doesn't understand Git tags, so you have to create a proper branch from the version tag you want to browse beforehand.

include/cpp-sort/detail/move.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019-2022 Morwenn
+ * Copyright (c) 2019-2025 Morwenn
  * SPDX-License-Identifier: MIT
  */
 #ifndef CPPSORT_DETAIL_MOVE_H_
@@ -102,8 +102,9 @@ namespace detail
         -> T*
     {
         using truth_type = std::integral_constant<bool,
-            std::is_trivial<value_type_t<InputIterator>>::value &&
-            std::is_trivial<T>::value
+            std::is_trivially_copyable<value_type_t<InputIterator>>::value &&
+            std::is_trivially_copyable<T>::value &&
+            sizeof(T) == sizeof(value_type_t<InputIterator>)
         >;
         return uninitialized_move_impl(truth_type{}, std::move(first), std::move(last),
                                        std::move(result), destroyer);

include/cpp-sort/probes/osc.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016-2022 Morwenn
+ * Copyright (c) 2016-2025 Morwenn
  * SPDX-License-Identifier: MIT
  */
 #ifndef CPPSORT_PROBES_OSC_H_
@@ -210,7 +210,12 @@ namespace probe
             static constexpr auto max_for_size(Integer n)
                 -> Integer
             {
-                return n == 0 ? 0 : (n * (n - 2) - 1) / 2;
+                if (n < 2) return 0;
+                if (n % 2 == 0) {
+                    return (n * (n - 2)) / 2;
+                } else {
+                    return (n * (n - 2) - 1) / 2;
+                }
             }
         };
     }

include/cpp-sort/version.h

@@ -9,6 +9,6 @@
 
 #define CPPSORT_VERSION_MAJOR 1
 #define CPPSORT_VERSION_MINOR 17
-#define CPPSORT_VERSION_PATCH 0
+#define CPPSORT_VERSION_PATCH 1
 
 #endif // CPPSORT_VERSION_H_

test_package/CMakeLists.txt

@@ -1,7 +1,7 @@
-# Copyright (c) 2018-2023 Morwenn
+# Copyright (c) 2018-2025 Morwenn
 # SPDX-License-Identifier: MIT
 
-cmake_minimum_required(VERSION 2.8.11)
+cmake_minimum_required(VERSION 3.5.0)
 
 project(test_package LANGUAGES CXX)
 

tests/CMakeLists.txt

@@ -27,7 +27,7 @@ else()
     message(STATUS "Catch2 not found")
     download_project(PROJ Catch2
                      GIT_REPOSITORY https://github.com/catchorg/Catch2
-                     GIT_TAG 2b60af89e23d28eefc081bc930831ee9d45ea58b  # v3.8.1
+                     GIT_TAG 25319fd3047c6bdcf3c0170e76fa526c77f99ca9  # v3.10.0
                      UPDATE_DISCONNECTED 1
     )
     add_subdirectory(${Catch2_SOURCE_DIR} ${Catch2_BINARY_DIR})
@@ -208,6 +208,7 @@ add_executable(main-tests
     distributions/ascending.cpp
     distributions/ascending_sawtooth.cpp
     distributions/descending.cpp
+    distributions/descending_plateau.cpp
     distributions/descending_sawtooth.cpp
     distributions/median_of_3_killer.cpp
     distributions/pipe_organ.cpp

tests/distributions/descending_plateau.cpp

@@ -0,0 +1,61 @@
+/*
+ * Copyright (c) 2025 Morwenn
+ * SPDX-License-Identifier: MIT
+ */
+#include <list>
+#include <vector>
+#include <catch2/catch_template_test_macros.hpp>
+#include <cpp-sort/sorters.h>
+#include <cpp-sort/utility/buffer.h>
+#include <cpp-sort/utility/functional.h>
+#include <testing-tools/distributions.h>
+#include "test_distribution.h"
+
+TEMPLATE_TEST_CASE( "test random-access sorters with descending_plateau distribution", "[distributions]",
+                    cppsort::adaptive_shivers_sorter,
+                    cppsort::cartesian_tree_sorter,
+                    cppsort::d_ary_heap_sorter<6>,
+                    cppsort::drop_merge_sorter,
+                    cppsort::grail_sorter<>,
+                    cppsort::grail_sorter<
+                        cppsort::utility::dynamic_buffer<cppsort::utility::sqrt>
+                    >,
+                    cppsort::heap_sorter,
+                    cppsort::mel_sorter,
+                    cppsort::merge_sorter,
+                    cppsort::pdq_sorter,
+                    cppsort::poplar_sorter,
+                    cppsort::quick_merge_sorter,
+                    cppsort::quick_sorter,
+                    cppsort::ska_sorter,
+                    cppsort::slab_sorter,
+                    cppsort::smooth_sorter,
+                    cppsort::spin_sorter,
+                    cppsort::splay_sorter,
+                    cppsort::split_sorter,
+                    cppsort::spread_sorter,
+                    cppsort::std_sorter,
+                    cppsort::tim_sorter,
+                    cppsort::verge_sorter,
+                    cppsort::wiki_sorter<>,
+                    cppsort::wiki_sorter<
+                        cppsort::utility::dynamic_buffer<cppsort::utility::half>
+                    > )
+{
+    std::vector<int> collection;
+    helpers::test_distribution<TestType>(collection, 10'000, dist::descending_plateau{});
+}
+
+TEMPLATE_TEST_CASE( "test bidirectional sorters with descending_plateau distribution", "[distributions]",
+                    cppsort::cartesian_tree_sorter,
+                    cppsort::drop_merge_sorter,
+                    cppsort::merge_sorter,
+                    cppsort::quick_merge_sorter,
+                    cppsort::quick_sorter,
+                    cppsort::slab_sorter,
+                    cppsort::splay_sorter,
+                    cppsort::verge_sorter )
+{
+    std::list<int> collection;
+    helpers::test_distribution<TestType>(collection, 1000, dist::descending_plateau{});
+}

tests/probes/osc.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016-2022 Morwenn
+ * Copyright (c) 2016-2025 Morwenn
  * SPDX-License-Identifier: MIT
  */
 #include <forward_list>
@@ -31,13 +31,27 @@ TEST_CASE( "presortedness measure: osc", "[probe][osc]" )
     {
         // Example from the paper Adaptive Heapsort
         // by Levcopoulos and Petersson, the upper bound
-        // should be (size * (size - 2) - 1) / 2
+        // should be:
+        // - When size is even: (size * (size - 2)) / 2
+        // - When size is odd: (size * (size - 2) - 1) / 2
 
-        std::forward_list<int> li = { 8, 5, 10, 3, 12, 1, 13, 2, 11, 4, 9, 6, 7 };
-        auto max_n = osc.max_for_size(cppsort::utility::size(li));
-        CHECK( max_n == 71 );
-        CHECK( osc(li) == max_n );
-        CHECK( osc(li.begin(), li.end()) == max_n );
+        // Even number of elements
+        {
+            const std::forward_list<int> li = { 8, 5, 10, 3, 12, 1, 13, 2, 11, 4, 9, 6 };
+            auto max_n = osc.max_for_size(cppsort::utility::size(li));
+            CHECK( max_n == 60 );
+            CHECK( osc(li) == max_n );
+            CHECK( osc(li.begin(), li.end()) == max_n );
+        }
+
+        // Odd number of elements
+        {
+            const std::forward_list<int> li = { 8, 5, 10, 3, 12, 1, 13, 2, 11, 4, 9, 6, 7 };
+            auto max_n = osc.max_for_size(cppsort::utility::size(li));
+            CHECK( max_n == 71 );
+            CHECK( osc(li) == max_n );
+            CHECK( osc(li.begin(), li.end()) == max_n );
+        }
     }
 
     SECTION( "regressions" )

tools/test_failing_sorter.cpp

@@ -71,6 +71,7 @@ void test(const char* name)
         << "osc: " << cppsort::probe::osc(copy2) << std::endl
         << "rem: " << cppsort::probe::rem(copy2) << std::endl
         << "runs: " << cppsort::probe::runs(copy2) << std::endl
+        << "spear: " << cppsort::probe::spear(copy2) << std::endl
         << "sus: " << cppsort::probe::sus(copy2) << std::endl
         << '\n';