This is a squashed commit. These are the original commit messages:
lib/option: Improve comment
better comment
Update documentation
Updated nixos/doc/manual/development/options-declarations.md with info on mkEnableOption and mkPackageOption.
Updated the comment on mkEnableOption in lib/options.nix
remove trailing whitespace
nixos/doc/option-declarations: Update IDs & formatting
nixos/docs/option-declarations: Escape angle brackets
Build DB from MD
(Amended) Fix typo
Co-authored-by: pennae <82953136+pennae@users.noreply.github.com>
(Amended) Build DB from MD (again)
This is a squashed commit. These are the original commit messages:
lib/options: Add mkPackageOption
lib/options: Add missing semicolon
lib/options.nix: Make mkPackageOption more complicated
lib/options: Fix indent. & spacing
lib/options.nix: Remove example and align comment
lib/options: ravenous overuse of arguments
lib/options: Format better
lib/options: Add default examplePath decl
lib/options: Make better mkPackageOption function
lib/options: Remove trailing whitespace
lib/options: Improve mkPackageOptions
lib/options: Remove pkgs prefixing
Co-authored-by: pennae <82953136+pennae@users.noreply.github.com>
lib/options: Slim down mkPackageOption further
lib/options: mkPackageOption: Add "pkgs." to example
lib/options: mkPackageOption: Make name & pkgs single arguments
lib/options: mkPackageOption: Swap name & pkgs
lib/options: Remove unnecessary import
Co-authored-by: pennae <82953136+pennae@users.noreply.github.com>
Allow a \n character at the end of the string and remove it during the
merge function.
An option of this type will resolve to the value "foo" whether it is set
to "foo" or "foo\n".
This is useful when using 'builtins.readFile' or ''-strings, which might
add an unintended newline (for example, bash trim the final newline from
a subshell).
`assert` has the annoying property that it dumps a lot of code at the
user without the built in capability to display a nicer message. We have
worked around this using `assertMsg` which would *additionally* display
a nice message. We can do even better: By using `throw` we can make
evaluation fail before assert draws its conclusions and prevent it from
displaying the code making up the assert condition, so we get the nicer
message of `throw` and the syntactical convenience of `assert`.
Before:
nix-repl> python.override { reproducibleBuild = true; stripBytecode = false; }
trace: Deterministic builds require stripping bytecode.
error: assertion (((lib).assertMsg (reproducibleBuild -> stripBytecode)) "Deterministic builds require stripping bytecode.") failed at /home/lukas/src/nix/nixpkgs/pkgs/development/interpreters/python/cpython/2.7/default.nix:45:1
After:
nix-repl> python.override { reproducibleBuild = true; stripBytecode = false; }
error: Deterministic builds require stripping bytecode.
Add a new type, inheriting 'types.str' but checking whether the value
doesn't contain any newline characters.
The motivation comes from a problem with the
'users.users.${u}.openssh.authorizedKeys' option.
It is easy to unintentionally insert a newline character at the end of a
string, or even in the middle, for example:
restricted_ssh_keys = command: keys:
let
prefix = ''
command="${command}",no-pty,no-agent-forwarding,no-port-forwarding,no-X11-forwarding
'';
in map (key: "${prefix} ${key}") keys;
The 'prefix' string ends with a newline, which ends up in the middle of
a key entry after a few manipulations.
This is problematic because the key file is built by concatenating all
the keys with 'concatStringsSep "\n"', with result in two entries for
the faulty key:
''
command="...",options...
MY_KEY
''
This is hard to debug and might be dangerous. This is now caught at
build time.
most modules can be evaluated for their documentation in a very
restricted environment that doesn't include all of nixpkgs. this
evaluation can then be cached and reused for subsequent builds, merging
only documentation that has changed into the cached set. since nixos
ships with a large number of modules of which only a few are used in any
given config this can save evaluation a huge percentage of nixos
options available in any given config.
in tests of this caching, despite having to copy most of nixos/, saves
about 80% of the time needed to build the system manual, or about two
second on the machine used for testing. build time for a full system
config shrank from 9.4s to 7.4s, while turning documentation off
entirely shortened the build to 7.1s.
- Eta reduce `mapAttrsRecursiveCond`, `foldAttrs`, `getAttrFromPath`.
- Modify `matchAttrs` to use `elemAt` instead of `head (tail xs)` to access
elements.
- Modify `matchAttrs` to use `any id` instead of `foldr and true`.
- Eta reduce formal arguments of `recursiveUpdate'.
- Access elements in `recursiveUpdateUntil` using `elemAt` and `head`
directly instead of `head (tail xs)` which copies a singleton unnecessarily.
(`elemAt` is used instead of `last` to save a primitive call to `length`,
this is possible because the 2-tuple structure is guranteed)
- Use `length` instead of comparison to empty list to save a copy.
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.
While it is a fact of life that aarch64-darwin is built on Hydra, it has
never formally been elevated from the Tier 7 state it was originally
assigned in RFC 0046. Since platform Tier status is not only
descriptive, but also normative, a consensus to commit to supporting
aarch64-darwin would need to be reached.
`builtins.currentSystem` is not available in pure eval. For this
particular test, we don't really care since it's all about generating
.drv files.
Fixes the following error:
$ nix flake check
warning: unknown flake output 'lib'
error: attribute 'currentSystem' missing
at /nix/store/8wvnlbjxlr90kq2qa6d9zjpj8rqkilr5-source/lib/tests/misc.nix:499:73:
498| let
499| deriv = derivation { name = "test"; builder = "/bin/sh"; system = builtins.currentSystem; };
| ^
500| in {
(use '--show-trace' to show detailed location informat
Move function spdxLicense, internally used in yarn2nix
to lib/meta.nix, and
rename to getLicenseFromSpdxId
A similar function is implemented in poetry2nix,
but the one originally in yarn2nix seems beter.
since it falls back to an license-like attrset
for mismatched case
instead of a plain string
Makes any programming errors more likely to show up early.
Non-obvious changes because of this:
- Ignore the `evalConfig` result in `reportFailure`; we're not checking
it at that point.
- Pre-increment `$fail` and `$pass` to make sure the arithmetic doesn't
result in a zero, which would result in a non-zero exit code for the
expression.
mkDerivedConfig : Option a -> (a -> Definition b) -> Definition b
Create config definitions with the same priority as the definition of another option.
This should be used for option definitions where one option sets the value of another as a convenience.
For instance a config file could be set with a `text` or `source` option, where text translates to a `source`
value using `mkDerivedConfig options.text (pkgs.writeText "filename.conf")`.
It takes care of setting the right priority using `mkOverride`.
recursiveUpdate does not produce an attrset until it has evaluated
both its arguments to weak head normal form.
nix-repl> lib.recursiveUpdate (throw "a") (throw "b")
error: b
nix-repl> lib.recursiveUpdate (throw "a") {}
error: a
The current implementation of `mutuallyExclusive` builds a new list with
length subtracted by one on every recursive call which is expensive. When
b is empty, the function still traverses a in its entirety before returning
a result.
The new implementation uses `any` to check if each element of list b is in
list a using `elem`. This maintains short circuiting when list a or b is empty
and has a worst case time complexity of O(nm).
the fix to extendDerivation in #140051 unwittingly worsened eval performance by
quite a bit. set elements alone needed over 1GB extra after the change, which
seems disproportionate to how small it was. if we flip the logic used to
determine which outputs to install around and keep a "this one exactly" flag in
the specific outputs instead of a "all of them" in the root we can avoid most
of that cost.
if extendDerivation is called on something that already had extendDerivation
called on it (eg a mkDerivation result) the second call will set
outputUnspecified=true on every output by way of propagating attributes of the
full derivation to the individual outputs. this in turn causes buildEnv--and
thus nix-shell and environment.systemPackages--to install every output of such a
derivation even when only a specific output was requested, which renders the
point of multiple outputs moot. this happens in python modules (see #139756),
though it seems that tcl and possibly others should also be affected.
PowerNV was looking for a nonexisting zImage file.
Remove unnecessary .file / .installTarget.
Also add config options needed for default minimal
NixOS config and QEMU VirtIO/VirtFS devices.
I'm working on a project that involves running a virtual machine
monitor program, which creates a control socket in the project
directory (because it doesn't make sense to put it anywhere else).
This obviously isn't part of the source of my program, so I think
cleanSource should filter it out.
Consider a derivation a value to be serialized.
nix-repl> lib.generators.toGitINI { hello = { drv = pkgs.hello; }; }
error: evaluation aborted with the following error message: 'generators.mkValueStringDefault: attrsets not supported: <derivation /nix/store/533q15q67sl6dl0272dyi7m7w5pwkkjh-hello-2.10.drv>'
Fixes #137390
The current implementation of the concatStringsSep fallback references
concatStrings whcih is just a partial application of concatStringsSep,
forming a circular dependency. Although this will almost never be
encountered as (assuming the user does not explicitly trigger it):
1. the or operator will short circuit both in lazy and strict
evaluation
2. this can only occur in Nix versions prior to 1.10
which is not compatible with various nix operations as of 2.3.15
However it is still important if scopedImport is used or the builtins
have been overwritten. lib.foldl' is used instead of builtins.foldl'
as the foldl' primops was introduced in the same release as concatStringsSep.
As suggested in #131205.
Now it's possible to pretty-print a value with `lib.generators` like
this:
with lib.generators;
toPretty { }
(withRecursion { depthLimit = 10; } /* arbitrarily complex value */)
Also, this can be used for any other pretty-printer now if needed.
The message I originally implemented here was to catch a mixup of
`config' and `options' in a `types.submodule'[1]. However it looks
rather weird for a wrongly declared top-level option.
So I decided to throw
error: The option `foo' does not exist. Definition values:
- In `<unknown-file>':
{
bar = {
_type = "option";
type = {
_type = "option-type";
...
It seems as you're trying to declare an option by placing it into `config' rather than `options'!
for an expression like
with import ./lib;
evalModules {
modules = [
{
foo.bar = mkOption {
type = types.str;
};
}
];
}
[1] fa30c9abed
When having a bogus declaration such as
{ lib, ... }:
{
foo.bar = mkOption {
type = types.str;
};
}
the evaluation will terminate with a not-so helpful
error: stack overflow (possible infinite recursion)
To make sure a useful error is still provided, I added a `depthLimit` of
`10` which should be perfectly sufficient to `toPretty` when it's used
in an error-case for `showDefs`.
When having e.g. recursive attr-set, it cannot be printed which is
solved by Nix itself like this:
$ nix-instantiate --eval -E 'let a.b = 1; a.c = a; in builtins.trace a 1'
trace: { b = 1; c = <CYCLE>; }
1
However, `generators.toPretty` tries to evaluate something until it's
done which can result in a spurious `stack-overflow`-error:
$ nix-instantiate --eval -E 'with import <nixpkgs/lib>; generators.toPretty { } (mkOption { type = types.str; })'
error: stack overflow (possible infinite recursion)
Those attr-sets are in fact rather common, one example is shown above, a
`types.<type>`-declaration is such an example. By adding an optional
`depthLimit`-argument, `toPretty` will stop evaluating as soon as the
limit is reached:
$ nix-instantiate --eval -E 'with import ./Projects/nixpkgs-update-int/lib; generators.toPretty { depthLimit = 2; } (mkOption { type = types.str; })' |xargs -0 echo -e
"{
_type = \"option\";
type = {
_type = \"option-type\";
check = <function>;
deprecationMessage = null;
description = \"string\";
emptyValue = { };
functor = {
binOp = <unevaluated>;
name = <unevaluated>;
payload = <unevaluated>;
type = <unevaluated>;
wrapped = <unevaluated>;
};
getSubModules = null;
getSubOptions = <function>;
merge = <function>;
name = \"str\";
nestedTypes = { };
substSubModules = <function>;
typeMerge = <function>;
};
}"
Optionally, it's also possible to let `toPretty` throw an error if the
limit is exceeded.
