Merge branch 'NixOS:master' into jxd/add-config

# systemd: break too long lines of Nix code

67643f8ec84bef1482204709073e417c9f07eb87

# {pkgs/development/cuda-modules,pkgs/test/cuda,pkgs/top-level/cuda-packages.nix}: reformat all CUDA files with nixfmt-rfc-style 2023-03-01

802a1b4d3338f24cbc4efd704616654456d75a94

# C compilers

/pkgs/development/compilers/gcc

/pkgs/development/compilers/llvm @RaitoBezarius

/pkgs/development/compilers/emscripten @raitobezarius

/doc/languages-frameworks/emscripten.section.md @raitobezarius

/nixos/modules/services/databases/postgresql.nix @thoughtpolice

/nixos/tests/postgresql.nix @thoughtpolice

# Linux kernel

/pkgs/os-specific/linux/kernel    @raitobezarius

/pkgs/top-level/linux-kernels.nix @raitobezarius

# Hardened profile & related modules

/nixos/modules/profiles/hardened.nix @joachifm

/nixos/modules/security/hidepid.nix @joachifm

        - pkgs/top-level/haskell-packages.nix

        - pkgs/top-level/release-haskell.nix

"6.topic: julia":

  - any:

    - changed-files:

      - any-glob-to-any-file:

        - doc/languages-frameworks/julia.section.md

        - pkgs/development/compilers/julia/**/*

        - pkgs/development/julia-modules/**/*

"6.topic: jupyter":

  - any:

    - changed-files:

  - any:

    - changed-files:

      - any-glob-to-any-file:

        - pkgs/development/tools/misc/luarocks/*

        - pkgs/development/interpreters/lua-5/**/*

        - pkgs/development/interpreters/luajit/**/*

        - pkgs/development/lua-modules/**/*

# This file was copied mostly from check-maintainers-sorted.yaml.

# NOTE: Formatting with the RFC-style nixfmt command is not yet stable. See

# https://github.com/NixOS/rfcs/pull/166.

# Because of this, this action is not yet enabled for all files -- only for

# those who have opted in.

name: Check that Nix files are formatted

on:

  pull_request_target:

permissions:

  contents: read

jobs:

  nixos:

    runs-on: ubuntu-latest

    if: github.repository_owner == 'NixOS'

    steps:

      - uses: actions/checkout@9bb56186c3b09b4f86b1c65136769dd318469633 # v4.1.2

        with:

          # pull_request_target checks out the base branch by default

          ref: refs/pull/${{ github.event.pull_request.number }}/merge

      - uses: cachix/install-nix-action@8887e596b4ee1134dae06b98d573bd674693f47c # v26

        with:

          # explicitly enable sandbox

          extra_nix_config: sandbox = true

      - name: Install nixfmt

        run: nix-env -f default.nix -iAP nixfmt-rfc-style

      - name: Check that Nix files are formatted according to the RFC style

        # Each environment variable beginning with NIX_FMT_PATHS_ is a list of

        # paths to check with nixfmt.

        env:

          # Format paths related to the Nixpkgs CUDA ecosystem.

          NIX_FMT_PATHS_CUDA: |

            pkgs/development/cuda-modules

            pkgs/test/cuda

            pkgs/top-level/cuda-packages.nix

        # Iterate over all environment variables beginning with NIX_FMT_PATHS_.

        run: |

          for env_var in "${!NIX_FMT_PATHS_@}"; do

            readarray -t paths <<< "${!env_var}"

            if [[ "${paths[*]}" == "" ]]; then

              echo "Error: $env_var is empty."

              exit 1

            fi

            echo "Checking paths: ${paths[@]}"

            if ! nixfmt --check "${paths[@]}"; then

              echo "Error: nixfmt failed."

              exit 1

            fi

          done

  ```nix

  foo {

    arg = ...;

    arg = <...>;

  }

  ```

  ```nix

  foo

  {

    arg = ...;

    arg = <...>;

  }

  ```

  Also fine is

  ```nix

  foo { arg = ...; }

  foo { arg = <...>; }

  ```

  if it's a short call.

- In attribute sets or lists that span multiple lines, the attribute names or list elements should be aligned:

  ```nix

  {

    # A long list.

    list = [

      elem1

        attr2 = "ggg";

      }

    ];

  }

  ```

- Short lists or attribute sets can be written on one line:

  ```nix

  {

    # A short list.

    list = [ elem1 elem2 elem3 ];

    # A short set.

    attrs = { x = 1280; y = 1024; };

  }

  ```

- Breaking in the middle of a function argument can give hard-to-read code, like

  ```nix

  { arg1, arg2 }:

  assert system == "i686-linux";

  stdenv.mkDerivation { ...

  stdenv.mkDerivation { /* ... */ }

  ```

  not

  ```nix

  { arg1, arg2 }:

    assert system == "i686-linux";

      stdenv.mkDerivation { ...

      stdenv.mkDerivation { /* ... */ }

  ```

- Function formal arguments are written as:

  ```nix

  { arg1, arg2, arg3 }:

  { arg1, arg2, arg3 }: { /* ... */ }

  ```

  but if they don't fit on one line they're written as:

  ```nix

  { arg1, arg2, arg3

  , arg4, ...

  , # Some comment...

    argN

  }:

  , arg4

  # Some comment...

  ,  argN

  }: { }

  ```

- Functions should list their expected arguments as precisely as possible. That is, write

  ```nix

  { stdenv, fetchurl, perl }: ...

  { stdenv, fetchurl, perl }: <...>

  ```

  instead of

  ```nix

  args: with args; ...

  args: with args; <...>

  ```

  or

  ```nix

  { stdenv, fetchurl, perl, ... }: ...

  { stdenv, fetchurl, perl, ... }: <...>

  ```

  For functions that are truly generic in the number of arguments (such as wrappers around `mkDerivation`) that have some required arguments, you should write them using an `@`-pattern:

  { stdenv, doCoverageAnalysis ? false, ... } @ args:

  stdenv.mkDerivation (args // {

    ... if doCoverageAnalysis then "bla" else "" ...

    foo = if doCoverageAnalysis then "bla" else "";

  })

  ```

  args:

  args.stdenv.mkDerivation (args // {

    ... if args ? doCoverageAnalysis && args.doCoverageAnalysis then "bla" else "" ...

    foo = if args ? doCoverageAnalysis && args.doCoverageAnalysis then "bla" else "";

  })

  ```

- Unnecessary string conversions should be avoided. Do

  ```nix

  {

    rev = version;

  }

  ```

  instead of

  ```nix

  {

    rev = "${version}";

  }

  ```

- Building lists conditionally _should_ be done with `lib.optional(s)` instead of using `if cond then [ ... ] else null` or `if cond then [ ... ] else [ ]`.

  ```nix

  {

    buildInputs = lib.optional stdenv.isDarwin iconv;

  }

  ```

  instead of

  ```nix

  {

    buildInputs = if stdenv.isDarwin then [ iconv ] else null;

  }

  ```

  As an exception, an explicit conditional expression with null can be used when fixing a important bug without triggering a mass rebuild.