[Nix-dev] yet another npm2nix reengineering attempt

[Sander van der Burg]

Haha :)

Well, I have been thinking about keeping the packages and all their
dependencies in their own store directories as well, but I eventually came
to the conclusion that it is impossible if you want to support the
inclusion of dependencies residing in any of the parent node_modules/
folders. :)

Although it would be possible to create store paths for each of the
packages involved (with their expected dependencies in their node_modules/
folder, leaving the ones that have been resolved by the includers out),
there is yet another problem -- the CommonJS module system dereferences
symlinks and looks relative from there. So that means that any package
resolves to a path in the Nix store first and then CommonJS looks in parent
directories from there. As you may know, the parent of the a Nix store path
is /nix/store, which makes it impossible for the CommonJS module system to
find any parent modules. :)

Second, we can't avoid omitting resolved parent dependencies, because we
also have to deal with crazy packages that have cyclic dependencies. The
reason that NPM "knows" how to handle them is because it omits dependencies
that have been encountered a second time. :)

So as you may see: it is all quite annoying and painful. :(

Maybe my solution is not the best/elegant, but it at least handles it.
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