add ghc filesystem (#962)

packages/g/ghc_filesystem/xmake.lua

@@ -0,0 +1,30 @@
+package("ghc_filesystem")
+    set_kind("library", {headeronly = true})
+    set_homepage("https://github.com/gulrak/filesystem")
+    set_description("An implementation of C++17 std::filesystem for C++11 /C++14/C++17/C++20 on Windows, macOS, Linux and FreeBSD.")
+    set_license("MIT")
+
+    add_urls("https://github.com/gulrak/filesystem/archive/refs/tags/$(version).tar.gz",
+             "https://github.com/gulrak/filesystem.git")
+    add_versions("v1.5.10", "9b96a024679807879fdfb30e46e8e461293666aeeee5fbf7f5af75aeacdfea29")
+
+    add_deps("cmake")
+
+    on_install(function (package)
+        local configs = {"-DGHC_FILESYSTEM_BUILD_TESTING=OFF", "-DGHC_FILESYSTEM_BUILD_EXAMPLES=OFF"}
+        table.insert(configs, "-DCMAKE_BUILD_TYPE=" .. (package:debug() and "Debug" or "Release"))
+        table.insert(configs, "-DBUILD_SHARED_LIBS=" .. (package:config("shared") and "ON" or "OFF"))
+        import("package.tools.cmake").install(package, configs)
+    end)
+
+    on_test(function (package)
+        assert(package:check_cxxsnippets({test = [[
+            #include <ghc/filesystem.hpp>
+            namespace fs = ghc::filesystem;
+            void test() {
+                fs::path dir{"."};
+                for (auto de : fs::directory_iterator(dir)) {
+                }
+            }
+        ]]}, {configs = {languages = "c++17"}}))
+    end)