build: deprecate experimental filesystem

Author: alandefreitas

.gitignore

@@ -22,6 +22,7 @@ CMakeSettings.json
 gh-md-toc
 /.vs
 /CMakeSettings.json
+.PVS-Studio
 
 # Hidden files
 .DS_Store

CMakeLists.txt

@@ -146,12 +146,6 @@ if (MATPLOTPP_BUILD_INSTALLER)
     # Install the file Matplot++Config.cmake
     install(FILES ${CMAKE_CURRENT_BINARY_DIR}/Matplot++Config.cmake
             DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/Matplot++)
-
-    # Install cmake to find filesystem as a dependency
-    if (NOT MATPLOTPP_BUILD_SHARED_LIBS)
-        install(FILES ${CMAKE_CURRENT_SOURCE_DIR}/cmake/FindFilesystem.cmake
-                DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/Matplot++)
-    endif ()
 endif ()
 
 #######################################################

Matplot++Config.cmake.in

@@ -15,7 +15,6 @@ if(NOT ${MATPLOT_BUILT_SHARED})
     include(CMakeFindDependencyMacro)
     list(APPEND CMAKE_MODULE_PATH ${MATPLOT_CONFIG_INSTALL_DIR})
     list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_LIST_DIR}")
-    find_dependency(Filesystem COMPONENTS Experimental Final)
     # OpenGL backend
     if (@MATPLOTPP_BUILD_EXPERIMENTAL_OPENGL_BACKEND@)
         find_dependency(glad)

source/matplot/CMakeLists.txt

@@ -1,7 +1,3 @@
-if(NOT MINGW)
-find_package(Filesystem REQUIRED COMPONENTS Experimental Final)
-endif()
-
 #######################################################
 ### Library                                         ###
 #######################################################
@@ -102,13 +98,7 @@ target_include_directories(matplot
            $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>)
 
 # Dependencies
-if(TARGET std::filesystem AND NOT MINGW)
-target_link_libraries_system(matplot
-  PRIVATE cimg nodesoup std::filesystem)
-else()
-target_link_libraries_system(matplot
-  PRIVATE cimg nodesoup)
-endif()
+target_link_libraries_system(matplot PRIVATE cimg nodesoup)
 
 # Required compiler features required
 # https://cmake.org/cmake/help/v3.14/manual/cmake-compile-features.7.html#requiring-language-standards
@@ -131,12 +121,6 @@ maybe_target_pedantic_warnings(matplot)
 #######################################################
 ### Definitions                                     ###
 #######################################################
-# Use experimental filesystem if std::filesystem is not available yet
-if(NOT MINGW)
-    if (CXX_FILESYSTEM_IS_EXPERIMENTAL)
-      target_compile_definitions(matplot PRIVATE CXX_FILESYSTEM_IS_EXPERIMENTAL)
-    endif()
-endif()
 # Some hack to not depend on FILE* internals
 # https://github.com/alandefreitas/matplotplusplus/issues/4
 include(CheckSymbolExists)

source/matplot/backend/gnuplot.cpp

@@ -3,18 +3,24 @@
 //
 
 #include "gnuplot.h"
-#ifdef CXX_FILESYSTEM_IS_EXPERIMENTAL
-#include <experimental/filesystem>
-#else
-#include <filesystem>
-#endif
+
 #include <cstdlib>
 #include <iostream>
 #include <matplot/util/common.h>
 #include <matplot/util/popen.h>
 #include <regex>
 #include <thread>
 
+#ifdef __has_include
+#if __has_include(<filesystem>)
+#include <filesystem>
+#else
+#define CXX_NO_FILESYSTEM
+#endif
+#else
+#define CXX_NO_FILESYSTEM
+#endif
+
 #ifdef MATPLOT_HAS_FBUFSIZE
 
 #include <stdio_ext.h>
@@ -116,14 +122,13 @@ namespace matplot::backend {
         }
 
         // look at the extension
-#ifdef CXX_FILESYSTEM_IS_EXPERIMENTAL
-        namespace fs = std::experimental::filesystem;
-#else
+#ifndef CXX_NO_FILESYSTEM
         namespace fs = std::filesystem;
-#endif
-
         fs::path p{filename};
         std::string ext = p.extension().string();
+#else
+        std::string ext = filename.substr(filename.find_last_of('.'));
+#endif
 
         // check terminal for that extension
         SV_CONSTEXPR auto exts = extension_terminal();
@@ -169,11 +174,8 @@ namespace matplot::backend {
         }
 
         // Create file if it does not exist
-#ifdef CXX_FILESYSTEM_IS_EXPERIMENTAL
-        namespace fs = std::experimental::filesystem;
-#else
+#ifndef CXX_NO_FILESYSTEM
         namespace fs = std::filesystem;
-#endif
         fs::path p{filename};
         if (!p.parent_path().empty() && !fs::exists(p.parent_path())) {
             fs::create_directory(p.parent_path());
@@ -183,12 +185,17 @@ namespace matplot::backend {
                 return false;
             }
         }
+#endif
 
         output_ = filename;
         terminal_ = format;
 
         // Append extension if needed
+#ifndef CXX_NO_FILESYSTEM
         std::string ext = p.extension().string();
+#else
+        std::string ext = filename.substr(filename.find_last_of('.'));
+#endif
         if (ext.empty()) {
             output_ += it->first;
         }