Transfom file path into Ruby nested Class using regex syntax transform

I try to change this (VSCode RELATIVE_FILEPATH variable):

app/service/namespace/important_thing/my_class.rb

into this:

Namespace::ImportantThing::MyClass

What I got so far:

RELATIVE_FILEPATH/(?:\\/?app\\/\\w+)?(\\/|_)(.(?!\\w+?\\.rb))/::${2:/upcase}/g}:

but the result is not great

::Namespace::Importand::Thing/my_class.rb

I'm doing this to create myself a snippet but this regex is a little bit to much for me.

I've used something similar in Sublime but there it was done with some code in python so can't be referenced from there.

Solution

You can use

"${RELATIVE_FILEPATH/^(?:.*?[\\\\\\/])?app[\\\\\\/]\\w+[\\\\\\/]|([^\\\\\\/]+?)(?:\\.rb$|([\\\\\\/]))/${1:/pascalcase}${2:+::}/g}"

See the regex demo. Details:

^(?:.*?[\\\/])?app[\\\/]\w+[\\\/] - start of string, any zero or more chars other than line break chars as few as possible, then \ or /, then an app, a \ or /, one or more word chars, \ or /
| - or
([^\\\/]+?) - Group 1: one or more chars other than \ and / as few as possible
(?:\.rb$|([\\\/])) - a non-capturing group matching either .rb at the end of string, or \ / / (captured into Group 2).

The replacement is ${1:/pascalcase}${2:+::}: