Broken `elm-pages build --base` - only changes outputs partially

[georgesboris]

I'm trying to build an elm-pages website that will be completely hosted inside a subpath of another site.

/blog/* -- elm-pages
/* -- something else

When using elm-pages dev --base=/blog everything seems to be working but when using elm-pages build --base=/blog I get this output:

/blog/index.html
/blog/post/index.html
/blog/category/index.html
api-patterns.json
all-paths.json
_redirects
elm.1234568.js
elm.js
elm.js.opt
route-patterns.json
style.css
template.html

This is problematic since some files are expected to be at the root of the website, not the specified path. However, I may be using elm-pages for another subpath (for any reason) or some other framework might want to use /style.css, etc. I would expect the --base option to change everything like this:

/blog/
  index.html
  post/index.html
  category/index.html
  api-patterns.json
  all-paths.json
  _redirects
  elm.1234568.js
  elm.js
  elm.js.opt
  route-patterns.json
  style.css
  template.html

Important this is not only problematic for conflict purposes but it is in fact broken since some of the links are expected to be at /paper/* even though they are still created at the root (e.g. elm.12345678.js, style.css, etc)