Pequenas correcoes nos valores de retorno de algumas funcoes.

Acrescimo do arquivo de testes.

tests/test.lua

@@ -0,0 +1,40 @@
+#!/usr/local/bin/lua
+
+local tmp = "/tmp"
+local sep = "/"
+local upper = ".."
+
+require"lfs"
+
+function attrdir (path)
+	for file in lfs.dir(path) do
+		if file ~= "." and file ~= ".." then
+			local f = path..'/'..file
+			print ("\t=> "..f.." <=")
+			local attr = lfs.attributes (f)
+			assert (type(attr) == "table")
+			if attr.mode == "directory" then
+				attrdir (f)
+			else
+				for name, value in pairs(attr) do
+					print (name, value)
+				end
+			end
+		end
+	end
+end
+
+-- Checking changing directories
+local current = assert (lfs.currentdir())
+local reldir = string.gsub (current, "^.*%"..sep.."([^"..sep.."])$", "%1")
+assert (lfs.chdir (upper), "could not change to upper directory")
+assert (lfs.chdir (reldir), "could not change back to current directory")
+assert (lfs.currentdir() == current, "error trying to change directories")
+assert (lfs.chdir ("this couldn't be an actual directory") == false, "could change to a non-existent directory")
+-- Changing creating and removing directories
+assert (lfs.mkdir (tmp.."/lfs_tmp_dir"), "could not make a new directory")
+assert (os.remove (tmp.."/lfs_tmp_dir"), "could not remove new directory")
+assert (lfs.mkdir (tmp.."/lfs_tmp_dir/lfs_tmp_dir") == false, "could create a directory inside a non-existent one")
+-- 
+assert (lfs.attributes ("this couldn't be an actual file") == false, "could get attributes of a non-existent file")
+assert (type(lfs.attributes (upper)) == "table", "couldn't get attributes of upper directory")