libfork: add package (#4028)

* libfork: add package

* add check

packages/l/libfork/xmake.lua

@@ -0,0 +1,43 @@
+package("libfork")
+    set_kind("library", {headeronly = true})
+    set_homepage("https://conorwilliams.github.io/libfork/")
+    set_description("A bleeding-edge, lock-free, wait-free, continuation-stealing tasking library built on C++20's coroutines")
+    set_license("MPL-2.0")
+
+    add_urls("https://github.com/ConorWilliams/libfork/archive/refs/tags/$(version).tar.gz",
+             "https://github.com/ConorWilliams/libfork.git")
+
+    add_versions("v3.8.0", "53f23f0d27bb0753c0b03132f3c17bf8099617f037a2389a04e85fdd6f2736e8")
+
+    if is_plat("linux", "bsd") then
+        add_syslinks("pthread")
+    end
+
+    add_deps("cmake")
+
+    if on_check then
+        on_check("windows", function (package)
+            import("core.tool.toolchain")
+
+            local msvc = toolchain.load("msvc", {plat = package:plat(), arch = package:arch()})
+            if msvc then
+                local vs = msvc:config("vs")
+                assert(vs and tonumber(vs) >= 2022, "package(libfork): need vs >= 2022")
+            end
+        end)
+    end    
+
+    on_install(function (package)
+        import("package.tools.cmake").install(package, {
+            "-DCMAKE_INSTALL_INCLUDEDIR=" .. package:installdir("include")
+        })
+    end)
+
+    on_test(function (package)
+        assert(package:check_cxxsnippets({test = [[
+            #include <libfork.hpp>
+            void test() {
+                lf::sync_wait(lf::lazy_pool{}, [](auto) -> lf::task<int>{ co_return 0; });
+            }
+        ]]}, {configs = {languages = "c++20"}}))
+    end)