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.
This will let us make assertions involving _module.args.pkgs, which
is not an option but a value attribute, and therefore doesn't have
its own highestPrio to inspect. The new function gives us that info.
with docbook gone and MD the default these aren't needed any more. we
can't remove them yet because there's thousands of uses, but maybe some
day we can.
This is to avoid stealing keys from submodules. `class` might be
common enough that reinterpreting existing `class` attributes in
configurations as a declaration leads to fairly widespread problems.
This is appears to be a fairly common mistake for beginners who want
to build larger things from the system configurations, such as NixOps
networks, etc. Further explanation seems appropriate.
The supposedly public nature of these functions has been holding
back module system maintenance, while usages of these functions
are expected to be rare. If used anywhere, presumably they're
emulating module system behavior because some use case isn't supported
properly. We should try to support such a use case directly, if it
even exists.
This makes the following work
disabledModules = [ foo.nixosModules.bar ];
even if `bar` is not a path, but rather a module such as
{ key = "/path/to/foo#nixosModules.bar"; config = ...; }
By supporting this, the user will often be able to use the same syntax
for both importing and disabling a module. This is becoming more relevant
because flakes promote the use of attributes to reference modules. Not
all of these modules in flake attributes will be identifiable, but with
the help of a framework such as flake-parts, these attributes can be
guaranteed to be identifiable (by outPath + attribute path).
unfortunately we can't unconditionally make this text markdown without
impacting downstream users of docs generation (as noted in #175586).
hide it entirely until the transition is complete.
mkAliasOptionModule should not default to mdDoc descriptions because
that can break out-of-tree users of documentation infrastructure. add an
explicitly-MD variant for now, to be removed some time after the MD
transition is complete.
Add a section on ordering option definitions.
Also mention `mkDefault` in the section on `mkOverride`.
Clarify the code a bit by renaming `defaultPriority` to
`defaultOverridePriority` and introducing `defaultOrderPriority`.
Add trace items that provide context for a failed definition that
can not be caught within the Nix language.
This also adds a test for the `tryEval` behavior of `showDefs`.
This attr provides the location of each definition.
This is particularly useful for introspecting options of type
`attrsOf`. E.g., it allows finding the location of a systemd
service definition by parsing
`options.systemd.services.definitionsWithLocations`.
This is particularly useful for disabling modules defined in a flake.
Example:
disabledModules = [ "${flake}/modules/mymodule.nix" ];
Previously, absolute string paths were internally prepended with `modulesPath`,
which caused the module filtering to fail.
`m` must always be an attrset at this point. It is basically always
evaluated. This will make it throw when any of the attrs is accessed,
rather than just `config`. We assume that this will improve the error
message in more scenarios.
This allows other module system consumers to
disable these docs via option merging.
For instance arion uses asciidoc instead of
docbook so that would look awful.
Documents the _module.args option, motivated by many usages in Flakes,
especially with the deprecation of extraArgs
(78ada83361)
The documentation rendering for this option had to be handled a bit
specially, since it's not declared in nixos/modules like all the other
NixOS options.
Co-Authored-By: pennae <github@quasiparticle.net>
Co-Authored-By: Robert Hensing <robert@roberthensing.nl>
types.optionSet has been deprecated for almost 10 years now
(0e333688ce)! A removal
was already attempted in 2019
(27982b408e), but it was promptly
reinstantiated since some third-party uses were discovered
(f531ce75e4).
It's finally time to remove it for good :)
This reverts commit 6b077c47ff.
Thanks Infinisil for discovering this problem:
> After a lot of trial and error, trying to prove why fixupOptionType should
> be used here or not, I figured it out: It's needed for the sake of file
> locations in error messages.
... where a bare submodule is an option that has a type like
`submoduleWith x`, as opposed to `attrsOf (submoduleWith x)`.
This makes migration unnecessary when introducing a freeform type
in an existing option tree.
Closes#146882
This ensures that the module file locations are propagated to the
freeform type, which makes it so that submodules in freeform types now
have their declaration location shown in the manual, fixing
https://github.com/NixOS/nixpkgs/issues/132085.
In addition, this also newly allows freeformTypes to be declared
multiple times and all declarations being merged together according to
normal option merging.
This also removes some awkwardness regarding the type of `freeformType`
the foldl is equivalent to a zip with concat. list concatenation in nix
is an O(n) operation, which makes this operation extremely inefficient
when large numbers of modules are involved.
this change reduces the number of list elements by 7 million on the
system used to write this, total memory spent on lists by 58MB, and
total memory allocated on the GC heap by almost 100MB (with a similar
reduction in GC heap size). it's also slightly faster.
