resolveId() - absolute paths of external modules are not to be converted to relative paths

[fanick1]

Expected Behavior / Situation

for some arbitrary module id a plugin with the resolveId() hook resolves this id to:

{
  id: '/some/absolute/path.haschode123.min.js',
  external: true
}

then this path is tranformed into the output file as-is

import foo from '/some/absolute/path.hashcode123.min.js'

Actual Behavior / Situation

this path is mangled in the output file into something like

import foo from '../../../../some/absolute/path.hashcode123.min.js'

which works in my case now only by accident (there are enough ../ to get to the root path in the browser)

Modification Proposal

do not path.relative() the id returned from resolveId when the id is marked as external.

using output.paths is not an option for me - I don't know the paths up front and I need to do some tricky resolutions

[fanick1]

I was lucky enough to run into a case where the rollup does not put enough '../' into the path and now the module (let's say the module in the example path.hashocde123.min.js) cannot be found because I am serving one module too deep in the URL structure.
A quick workaround I had to do is to prepend the module id returned from the resolveId() with few '../' :

{
  id: '../../../../../../../../../some/absolute/path.haschode123.min.js',
  external: true
}

This of course still leaves room for error. I really think that external modules with a leading '/' in the name should be treated as absolute paths.

[fanick1]

I believe this is the same issue as in #3831.

[lukastaegert]

Fix at fix at #4021