use absolute paths and remove sourceRoot when generating sourcemaps

[brokenmass]

What kind of change does this PR introduce?
bugfix

Did you add tests for your changes?
Yes

If relevant, did you update the README?
Not relevant

Summary
Simplifies and correct sourcemaps generation by returning absolute sources paths and removing sourceRoot.
Fix #373 and #280

Does this PR introduce a breaking change?
No

Other information

[codecov]

Codecov Report

Merging #430 into master will decrease coverage by -0.03%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #430      +/-   ##
==========================================
- Coverage   98.35%   98.32%   -0.03%     
==========================================
  Files           9        9              
  Lines         304      299       -5     
  Branches       69       67       -2     
==========================================
- Hits          299      294       -5     
  Misses          5        5

Impacted Files	Coverage Δ
lib/loader.js	100% <100%> (ø)	✅

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[brokenmass]

any updates ?

[joshwiens]

@brokenmass for reference ping @webpack-contrib/org-maintainers as it's easy to miss comments in the news feed and watching 43 repositories is a nightmare :)

[michael-ciniawsky]

@brokenmass 👍

[jasisk]

This change appears to introduce some complexity for using, e.g., chrome dev tools.

Because css-loader is no longer following the same convention as webpack's source mapping, you end up having to add multiple workspace mappings. I presently store my css alongside the component it corresponds to. I could not figure out the exact incantation of mappings to get everything to work.

Additionally, without a protocol, Chrome treats the path as an absolute path after the host. So, on a Mac, it resolves to http://something.website:port/Users/myUserName/....

[joshwiens]

@jasisk - Can you get this into a new issue so we are sure this can be addressed one way or another

[michael-ciniawsky]

Yep please open a new issues this is a very inconvenient regression to said it politely, we need to investigate in a clean way 😛

[davicho]

I find paths absolute slightly inconvenient. As I inspect my css in the dev tools.... the path can be so long it truncates the actual file name - making have to leave my work are to hover of the path and get the tooltip to see the actual file name I need to work on. (Unless, there is an option to undo this but I have looked and have not seen such). Ty.