mediawiki-extensions-Scribunto/engines/LuaCommon/lualib/package.lua
Brad Jorsch 0a8a07de2f Fix package.loaded and other cleanups
The listing of the standard modules in package.loaded seems to have been
removed to avoid leaking information to loaded modules. However, since
the *entire* environment is cloned, *including* package.loaded itself,
this does not seem to actually be a problem. But for good measure, also
add a unit test to verify that the version of the standard module tables
referenced from package.loaded is the same as that in _G.

This change also cleans up some unused local variables and an unused
local function from the package module.

Change-Id: I7ec8227b3273059e8f65ad735c215bfd0c623e64
2013-01-30 17:24:09 +00:00

128 lines
3.7 KiB
Lua

--[[
-- A package library similar to the one that comes with Lua 5.1, but without
-- the local filesystem access. Based on Compat-5.1 which comes with the
-- following license notice:
--
-- Copyright © 2004-2006 The Kepler Project.
--
-- Permission is hereby granted, free of charge, to any person obtaining a copy of
-- this software and associated documentation files (the "Software"), to deal in
-- the Software without restriction, including without limitation the rights to
-- use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
-- the Software, and to permit persons to whom the Software is furnished to do so,
-- subject to the following conditions:
--
-- The above copyright notice and this permission notice shall be included in all
-- copies or substantial portions of the Software.
--
-- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
-- FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
-- COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
-- IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
-- CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
--]]
local assert, error, ipairs, setmetatable, type = assert, error, ipairs, setmetatable, type
local format = string.format
--
-- avoid overwriting the package table if it's already there
--
package = package or {}
local _PACKAGE = package
package.loaded = package.loaded or {}
package.loaded.debug = debug
package.loaded.string = string
package.loaded.math = math
package.loaded.io = io
package.loaded.os = os
package.loaded.table = table
package.loaded._G = _G
package.loaded.coroutine = coroutine
package.loaded.package = package
local _LOADED = package.loaded
--
-- avoid overwriting the package.preload table if it's already there
--
package.preload = package.preload or {}
local _PRELOAD = package.preload
--
-- check whether library is already loaded
--
local function loader_preload (name)
assert (type(name) == "string", format (
"bad argument #1 to `require' (string expected, got %s)", type(name)))
assert (type(_PRELOAD) == "table", "`package.preload' must be a table")
return _PRELOAD[name]
end
-- create `loaders' table
package.loaders = package.loaders or { loader_preload }
local _LOADERS = package.loaders
--
-- iterate over available loaders
--
local function load (name, loaders)
-- iterate over available loaders
assert (type (loaders) == "table", "`package.loaders' must be a table")
for i, loader in ipairs (loaders) do
local f = loader (name)
if f then
return f
end
end
error (format ("module `%s' not found", name))
end
-- sentinel
local sentinel = function () end
--
-- require
--
function _G.require (modname)
assert (type(modname) == "string", format (
"bad argument #1 to `require' (string expected, got %s)", type(name)))
local p = _LOADED[modname]
if p then -- is it there?
if p == sentinel then
error (format ("loop or previous error loading module '%s'", modname))
end
return p -- package is already loaded
end
local init = load (modname, _LOADERS)
_LOADED[modname] = sentinel
local actual_arg = _G.arg
_G.arg = { modname }
local res = init (modname)
if res then
_LOADED[modname] = res
end
_G.arg = actual_arg
if _LOADED[modname] == sentinel then
_LOADED[modname] = true
end
return _LOADED[modname]
end
--
-- package.seeall function
--
function _PACKAGE.seeall (module)
local t = type(module)
assert (t == "table", "bad argument #1 to package.seeall (table expected, got "..t..")")
local meta = getmetatable (module)
if not meta then
meta = {}
setmetatable (module, meta)
end
meta.__index = _G
end