Support `--characters` from a file

[madig]

I want to test the following chars:

!"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~ ¡¢£¥§¨©ª«®¯°²³´¶·¸¹º»¿ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖ×ØÙÚÛÜÝÞßàáâãäåæçèéêëìíîïðñòóôõö÷øùúûüýþÿĀāĂ㥹ĆćĊċČčĎďĐđĒēĖėĘęĚěĞğĠġĢģĦħĪīĮįİıIJijĶķĹĺĻļĽľĿŁłŃńŅņŇňŊŋŌōŐőŒœŔŕŖŗŘřŚśŞşŠšŢţŤťŪūŬŭŮůŰűŲųŴŵŶŷŸŹźŻżŽžǍȘșȚțȷˆˇ˘˙˚˛˜˝ẀẁẂẃẄẅẞỲỳ –—‘’‚“”„•…‹›⁄⁰⁴⁵⁶⁷⁸⁹₀₁₂₃₄₅₆₇₈₉€™−◌

I can't though, because there's special characters in there, so I have to fight my shell's escaping rules and then ninja's (because the string is inserted verbatim). Please add a way to have the code read the characters from a file.

[madig]

Oh, I have to escape them for regex parsing as well. Ugh.

[m4rc1e]

Sorry I've just seen this (had a kid born that day). I'll add this.

[m4rc1e]

Apologies but the implementation of the --characters arg is probably different to what you expect. Currently, it expects regex ranges such as [0-9|A-z] in order for it to work. Your expression will work if it's encapsulated by [ and ] and the special regex characters such as ()[]{}-| are escaped by forward slashes. I'll still open a pr for you since having this in a file does make sense.