Is this a bug with onPlayerVehicleExit?

[Franc[e]sco]

Take a look at this snippet:

addEventHandler("onPlayerVehicleExit", getRootElement(), 
    function(vehicle, seat, jacker) 
        if(seat == 0 and not starting_timeattack) then 
            if(jacker == nil) then 
                destroyElement(vehicle) 
                setElementData(source, "current_vehicle", nil) 
            else 
                local jackername = getPlayerName(jacker) 
                outputChatBox(jackername .. " tried to steal your car!", source) 
                warpPedIntoVehicle(source, vehicle) 
            end 
        end 
        if(starting_timeattack) then 
            starting_timeattack = false 
        else 
            if(getElementData(source, "isChallengingAkinaTimeAttack")) then 
                triggerEvent("quitAkinaTimeAttack", source) 
            end 
        end 
    end 
) 

jacker is supposed to be nil when no one is jacking you and you are just exiting your own car, right?

Well, when i exit my own car without anyone jacking it, it still executes the part for getting jacked, this one:

            else 
                local jackername = getPlayerName(jacker) 
                outputChatBox(jackername .. " tried to steal your car!", source) 
                warpPedIntoVehicle(source, vehicle) 
            end 

and, of course, getPlayerName throws an invalid argument error

[BinSlayer1]

jacker is supposed to be nil when no one is jacking you and you are just exiting your own car, right?

Well, not necessarily since the wiki doesn't explain it should contain "nil". You should try "false" as well

[Franc[e]sco]

False worked! Thank you very much!

[BinSlayer1]

dont mention it