--------------------------------------------------------------------------------
-- Lua 5.2 compat

if not setfenv then -- Lua 5.2
  -- based on http://lua-users.org/lists/lua-l/2010-06/msg00314.html
  -- this assumes f is a function
  local function findenv(f)
    local level = 1
    repeat
      local name, value = debug.getupvalue(f, level)
      if name == '_ENV' then return level, value end
      level = level + 1
    until name == nil
    return nil end
  getfenv = function (f) return(select(2, findenv(f)) or _G) end
  setfenv = function (f, t)
    local level = findenv(f)
    if level then debug.setupvalue(f, level, t) end
    return f end
end

--------------------------------------------------------------------------------

local SUITE = require('TestSuite').new('resilience')
SUITE:setEnviroment{
    setfenv = setfenv
}

--------------------------------------------------------------------------------

SUITE:addTest('no_std_lib', function ()
    -- This tests whether one could load the library with an empty env, without
    -- an error.
    local chunk = loadfile('./library.lua')
    setfenv(chunk, {})
    local library = chunk()

    for func, func_info in pairs(library) do
        error(('For some reason %s is defined in the library'):format(func_info.name))
    end
end)

SUITE:addTest('a_very_small_part_of_math', function ()
    -- This tests whether one could load the library with an empty env, without
    -- an error.
    local chunk = loadfile('./library.lua')
    setfenv(chunk, { math = { abs = math.abs } })
    local library = chunk()

    assert( library[math.abs], 'Why is math.abs not defined in the library?' )
end)

--------------------------------------------------------------------------------

return SUITE