feat: allow regexp for the pattern

[RodrigoEspinosa]

Summary

The patter attribute needs to be a string. However, some editors (like in a brand new VSCode) will automatically detect "unnecessary" scapes in strings and remove them, making it harder to send those as strings.

For instance, this ^[:alnum:]+\@[:alnum:\.]\:(\/[:alnum:]+)*$ will be saved as ^[:alnum:]+@[:alnum:.]:(/[:alnum:]+)*$ automatically.

As a workaround, we can do something like /^[:alnum:]+\@[:alnum:\.]\:(\/[:alnum:]+)*$/.toString() and then remove the first and last /, but it would be nice if we can send the regular expression from the beginning.

schemasafe/src/compile.js

Line 481 in 3f4dc5f

handle('pattern', ['string'], (pattern) => {

[ChALkeR]

I don't understand.

What is wrong with ^[:alnum:]+@[:alnum:.]:(/[:alnum:]+)*$?

Additional escaping is needed for / in literal regexps only.
I.e.:

> /a\/b/.source === new RegExp('a/b').source
true

Could you share an example that has behavior (i.e. validation) differences?

[ChALkeR]

If . is supposed to be a dot (and not any char), ^[:alnum:]+@[:alnum:\.]:(/[:alnum:]+)*$ should be encoded as "^[:alnum:]+@[:alnum:\\.]:(/[:alnum:]+)*$" as a string, for example.

[RodrigoEspinosa]

Thanks for the clarification, @ChALkeR!