The `importApply` docs reference using the `_key` attr along with
`importApply` or `_file`, however the actual attr name used by the
module system is `key`.
Format all Nix files using the officially approved formatter,
making the CI check introduced in the previous commit succeed:
nix-build ci -A fmt.check
This is the next step of the of the [implementation](https://github.com/NixOS/nixfmt/issues/153)
of the accepted [RFC 166](https://github.com/NixOS/rfcs/pull/166).
This commit will lead to merge conflicts for a number of PRs,
up to an estimated ~1100 (~33%) among the PRs with activity in the past 2
months, but that should be lower than what it would be without the previous
[partial treewide format](https://github.com/NixOS/nixpkgs/pull/322537).
Merge conflicts caused by this commit can now automatically be resolved while rebasing using the
[auto-rebase script](8616af08d9/maintainers/scripts/auto-rebase).
If you run into any problems regarding any of this, please reach out to the
[formatting team](https://nixos.org/community/teams/formatting/) by
pinging @NixOS/nix-formatting.
Passing the elaborated system defeats what pkgs/top-level/default.nix
tries to do: Pass only the original args and let defaults be inferred.
The underlying problem is that lib.systems.elaborate can not deal with
arbitrary overrides, but will often return an inconsistent system
description when partially overriding some values. This becomes most
prominent if trying to override an already elaborated system.
* lib.modules.importApply: init
Brings variables from rich scopes to modules defined in separate files.
A helper for functions in files that return a module.
* lib.modules.importApply: Edit doc
Generally improve the quality. Notes:
- Not rendered to the manual yet, so probably the syntax could be
improved, but I have no way to test this now.
- The docs use `arg` vs `staticArg` in the code. This is intentional,
because the doc is pretty clear about the role of `arg` whereas
the code exists in a context where ambiguities are more harmful.
* Format
Benefits:
- some lookups happened in the hot path, and will now be slightly faster,
with only a variable lookup and no attribute selection
- it's now harder to accidentally use args.lib aka specialArgs.lib, which
has happened
- shorter
The practical use for this should be very limited because I don't
think anyone should change `lib`, let alone change `lib.functionArgs`,
but, but it would be even stranger to rely on `args.lib` (or really
`specialArgs.lib` for what's clearly a behavior of the current
`evalModules`, which uses its own ambient lib for basically everything.
The shadowing of `lib` by `args.lib` here seems to be a small mistake,
which is easy to make.
What it does: line and column level *declaration* position information:
$ nix repl .
nix-repl> :p nixosConfigurations.micro.options.environment.systemPackages.declarationPositions
[ { column = 7; file = "/nix/store/24aj3k7fgqv3ly7qkbf98qvphasrw9nb-source/nixos/modules/config/system-path.nix"; line = 63; } ]
Use cases:
- ctags over NixOS options, as will be presented at NixCon 2023 ;)
- improving the documentation pages to go to the exact line of the
declarations.
Related work:
- https://github.com/NixOS/nixpkgs/pull/65024
This one does it for all *definitions* rather than declarations, and
it was not followed through with due to performance worries.
- https://github.com/NixOS/nixpkgs/pull/208173
The basis for this change. This change is just a rebase of that one.
I split it out to add the capability before adding users of it, in
order to simplify review. However, the ctags script in there is a
sample user of this feature.
Benchmarks: conducted by evaluating my own reasonably complex NixOS
configuration with the command:
`hyperfine -S none -w 1 -- "nix eval .#nixosConfigurations.snowflake.config.system.build.toplevel.outPath"`
```
Benchmark 1: nix eval .#nixosConfigurations.snowflake.config.system.build.toplevel.outPath
Time (mean ± σ): 8.971 s ± 0.254 s [User: 5.872 s, System: 1.388 s]
Range (min … max): 8.574 s … 9.327 s 10 runs
Benchmark 1: nix eval .#nixosConfigurations.snowflake.config.system.build.toplevel.outPath
Time (mean ± σ): 8.766 s ± 0.160 s [User: 5.873 s, System: 1.346 s]
Range (min … max): 8.496 s … 9.033 s 10 runs
```
Summary of results: it seems to be in the noise, this does not cause any
visible regression in times.
mkOption does not require a `type` argument and does not set the
resulting attribute if it is not given. Consequently, we need to be
prepared to merge options that have no type information.
This is a non-trivial refactor that slightly changes the semantics
of the internal definition lists.
Whereas previously only individual list items would trigger the exception,
now the error is promoted to the whole list.
This is mostly ok, because we compute the value, it is wrong to ignore a definition.
However, we don't always compute the value. For instance `readOnly`
only needs to count definitions. That won't be possible anymore when
the error is raised for one of the items. As a consequence, an error
will be raised for the errant definition instead of the number of
definitions.
