解析Lua函数

使用Lua语言解析Lua脚本中的函数，打印函数名和函数参数。考虑匿名函数 ，共计入了4种定义函数的形式。

function printFunction()
    local handle = io.popen('需要解析的脚本文件夹路径')
    local resultFile = io.open('存放结果的文件路径', 'w')
    for file in handle:lines() do
        local temp, _ = string.find(file, '.lua')
        if temp then
            resultFile:write("fileName: " .. file)
            resultFile:write("\n")
            local fileHandle = io.open(file, "r")
            local tempLines = ""
            for line in fileHandle:lines() do
                local commentLoc, _ = string.find(line, '%-%-')
                -- 去除注释
                if commentLoc then
                    line = string.sub(line, 1, commentLoc - 1)
                end
                line = line .. "\n"
                -- 考虑逗号后面换行的情况，进行拼接
                tempLines = tempLines .. line
                local nextPos, _ = string.find(line, ',%s*\n')
                if not nextPos then
                    -- function xx(...)
                    local _, leftBorder1, functionName1 = string.find(tempLines, 'function%s+([%a_%d]+)%s*%(')
                    -- xx = function(...)
                    local _, leftBorder2, functionName2 = string.find(tempLines, "%[[\'\"]([%a_%d]+)[\'\"]%]%s*=%s*function%s*%(")
                    -- ['xx'] = function(...)
                    local _, leftBorder3, functionName3 = string.find(tempLines, '([%a_%d]+)%s*=%s*function%s*%(')
                    -- function(...)，没有名字也没有赋值给任何变量，被当作参数传递
                    local _, leftBorder4 = string.find(tempLines, '[^%a^_^%d]function%s*%(')
                    local functionName4 = leftBorder4 and ""
                    
                    -- 找到第一个可以匹配的名字
                    local functionName = functionName1 or functionName2 or functionName3 or functionName4
                    if functionName then
                        resultFile:write("functionName: " .. functionName)
                        resultFile:write("\n")
                        local leftBorder = leftBorder1 or leftBorder2 or leftBorder3 or leftBorder4
                        local endPos, _ = string.find(tempLines, '%)', leftBorder + 1) or 0
                        local subLine = string.sub(tempLines, leftBorder + 1, endPos - 1)
                        for argName in string.gmatch(subLine, '[%a_%d]+') do
                            resultFile:write("argName: ", argName)
                            resultFile:write("\n")
                        end
                    end
                    tempLines = ""
                end
            end
            fileHandle:close()
        end
    end
    resultFile:close()
    handle:close()
end