improve libpng

packages/l/libpng/xmake.lua

@@ -13,6 +13,8 @@ package("libpng")
         add_deps("cmake")
     end
 
+    add_links("png")
+
     on_install("windows", function (package)
         import("package.tools.cmake").install(package)
     end)

scripts/test.lua

@@ -21,6 +21,7 @@ function main(...)
     os.cd(workdir)
     os.exec("xmake create test")
     os.cd("test")
+    print(os.curdir())
     os.exec("xmake repo --add local-repo %s", repodir)
     os.exec("xmake repo -l")
     os.exec("xmake require -f -v -D -y %s", table.concat(packages, " "))