Now that SourcePath uses a SourceAccessor instead of an InputAccessor,
we can use it in function signatures instead of passing a
SourceAccessor and CanonPath separately.
More invariants are enforced in the type, and less state needs to be
stored in the main sink itself. The method here is roughly that known as
"session types".
Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
Today, with the tests inside a `tests` intermingled with the
corresponding library's source code, we have a few problems:
- We have to be careful that wildcards don't end up with tests being
built as part of Nix proper, or test headers being installed as part
of Nix proper.
- Tests in libraries but not executables is not right:
- It means each executable runs the previous unit tests again, because
it needs the libraries.
- It doesn't work right on Windows, which doesn't want you to load a
DLL just for the side global variable . It could be made to work
with the dlopen equivalent, but that's gross!
This reorg solves these problems.
There is a remaining problem which is that sibbling headers (like
`hash.hh` the test header vs `hash.hh` the main `libnixutil` header) end
up shadowing each other. This PR doesn't solve that. That is left as
future work for a future PR.
Co-authored-by: Valentin Gagarin <valentin.gagarin@tweag.io>