Script to compare Python's os.path.normpath and Penlight's pl.path.normpath on random inputs

test-normpath.lua

-- Usage: lua test-normpath.lua [count | path]
local path = require "pl.path"
local socket = require "socket"

math.randomseed(math.floor(socket.gettime() * 1000))

local chars = "./A"

local function gen_random_path()
   local length = math.random(0, 5) + math.random(0, 5)
   local buf = {}

   for i = 1, length do
      local char_index = math.random(#chars)
      buf[i] = chars:sub(char_index, char_index)
   end

   return table.concat(buf)
end

local function test_path(p)
   local pl_normpath = path.normpath(p)

   local py_command = ([[python -c 'import os, sys; sys.stdout.write(os.path.normpath("%s"))']]):format(p)
   local py_handler = assert(io.popen(py_command))
   local py_normpath = py_handler:read("*a")
   py_handler:close()

   if pl_normpath ~= py_normpath then
      print("Mismatch!")
      print("   path: " .. p)
      print("     pl: " .. pl_normpath)
      print("     py: " .. py_normpath)
   end
end

if arg[1] and not tonumber(arg[1]) then
   test_path(arg[1])
else
   for _ = 1, tonumber(arg[1] or "10") do
      test_path(gen_random_path())
   end
end