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.
- Remove inheritance of `lists.fold` as it isn't used anywhere.
- Inherit `foldl'` for consistency as only `cartesianProductOfSets` explicitly
reference lib.
- Inline `foldr` to generate nested attrs instead of using `listToAttrs` and `tail`.
This allows checking e.g. stdenv.hostPlatform.isGnu, just like isMusl
or isUClibc. It was already possible to check for glibc with
stdenv.hostPlatform.libc == "glibc", but when that doesn't line up
with how every other platform check works, this is apparently
sufficiently non-obvious that we've ended up with stuff like adding
glibc.static if !isMusl, which is obviously wrong.
This regressed in 9c213398b3
The recursiveUpdate gave the platform both gcc.cpu and gcc.arch attrs
instead of only gcc.cpu. This is invalid; gcc configuration fails with:
```
Switch "--with-arch" may not be used with switch "--with-cpu"
```
So we revert to using `//` to retain only gcc.cpu
(which is more specific than the processor arch).
Trying to create a simple flake with input:
```
{
inputs.nixpkgs-lib.url = "github:NixOS/nixpkgs?dir=lib";
outputs = {nixpkgs-lib, ...}: { };
}
```
Fails when trying to evaluate the nixpkgs-lib flake with an error like:
```
error: getting status of '/nix/store/xxxx-source/lib/lib': No such file or directory
(use '--show-trace' to show detailed location information)
```
Allows for distinction of licenses that are unfree overall but do grant the
right to redistribute. Defaults to the freeness of the license.
Note: Many unfree but are redistributable licenses aren't marked as such.
I expect that to be fixed in a distributed manner over time.
Closes https://github.com/NixOS/nixpkgs/pull/97789
Previously, if a derivation without a `drvPath` was handled, an error
would be thrown:
nix-repl> lib.generators.toPretty {} { type = "derivation"; }
error: attribute 'drvPath' missing, at /home/infinisil/src/nixpkgs/lib/generators.nix:251:24
With this commit it doesn't anymore:
nix-repl> lib.generators.toPretty {} { type = "derivation"; }
"<derivation ???>"
This matches what `nix repl` outputs:
nix-repl> { type = "derivation"; }
«derivation ???»
For an option definition that uses `lib.options.mergeEqualOption`
underneath, like `types.anything`, an error is thrown when multiple
functions are assigned, indicating that functions can't be compared for
equivalence:
error: The option `test' has conflicting definition values:
- In `xxx': <function>
- In `xxx': <function>
(use '--show-trace' to show detailed location information)
However, the error message didn't use the correct files. While above
error indicates that both definitions are in the xxx file, that's in
fact not true. Above error was generated with
options.test = lib.mkOption {
type = lib.types.anything;
};
imports = [
{
_file = "yyy";
test = y: y;
}
{
_file = "xxx";
test = x: x;
}
];
With this change, the error uses the correct file locations:
error: The option `test' has conflicting definition values:
- In `xxx': <function>
- In `yyy': <function>
(use '--show-trace' to show detailed location information)
so the underlaying use case of the preceding commit is so
generic, that we gain a lot in reasoning to give it an
appropriate name.
As the comment states:
image media needs to override host config short of mkForce
m68k was recently added for Linux and none, but NetBSD also supports
m68k. Nothing will build yet, but I want to make sure we at least
encode the existence of NetBSD support for every applicable
architecture we support for other operating systems.
In Autoconf, some old NetBSD targets like "i686-unknown-netbsd" are
interpreted as a.out, not elf, and virtually nothing supports it. We
need to specify e.g. "i686-unknown-netbsdelf" to get the right
behaviour.
