Fuzz testing

[notriddle]

Write something that generates random strings, and attempts to parse them, ensuring that the library doesn't panic. After doing so, make sure the library can run the pre_request check random URLs against it also without panicking.

[notriddle]

Being a good first issue, and since we want to avoid having two different people working on the same thing, please leave a comment saying that you want to claim the issue. I'll remove the good first issue and add the assigned label to it.