重置 Lua 测试后的 package.loaded

对我来说，只要浅复制 package.loaded 和 _G 就足够了。可以在这里找到浅复制函数：http://lua-users.org/wiki/CopyTable：

function shallowcopy(orig)
    local orig_type = type(orig)
    local copy
    if orig_type == 'table' then
        copy = {}
        for orig_key, orig_value in pairs(orig) do
            copy[orig_key] = orig_value
        end
    else -- number, string, boolean, etc
        copy = orig
    end
    return copy
end

实际测试如下：

local packageLoadedCopy = shallowcopy(package.loaded)
local gCopy = shallowcopy(_G)
for _, test in ipairs(tests) do
    -- 做出实际的测试
    -- 清理环境
    local markDeletion = {}
    local markModify = {}
    for name in pairs(package.loaded) do
        if not packageLoadedCopy[name] then
            table.insert(markDeletion, name)
        elseif packageLoadedCopy[name] ~= package.loaded[name] then
            table.insert(markModify, name)
        end
    end
    for _, name in pairs(markDeletion) do
        package.loaded[name] = nil
    end
    for _, name in pairs(markModify) do
        package.loaded[name] = packageLoadedCopy[name]
    end
    markDeletion, markModify = {}, {}
    for name in pairs(_G) do
        if not gCopy[name] then
            table.insert(markDeletion, name)
        elseif _G[name] ~= gCopy[name] then
            table.insert(markModify, name)
        end
    end
    for _, name in pairs(markDeletion) do
        _G[name] = nil
    end
    for _, name in pairs(markModify) do
        _G[name] = gCopy[name]
    end
end

请注意，简单地

package.loaded = packageLoadedCopy
_G = gCopy

不起作用，我不确定为什么。