the conversion procedure is simple:
- find all things that look like options, ie calls to either `mkOption`
or `lib.mkOption` that take an attrset. remember the attrset as the
option
- for all options, find a `description` attribute who's value is not a
call to `mdDoc` or `lib.mdDoc`
- textually convert the entire value of the attribute to MD with a few
simple regexes (the set from mdize-module.sh)
- if the change produced a change in the manual output, discard
- if the change kept the manual unchanged, add some text to the
description to make sure we've actually found an option. if the
manual changes this time, keep the converted description
this procedure converts 80% of nixos options to markdown. around 2000
options remain to be inspected, but most of those fail the "does not
change the manual output check": currently the MD conversion process
does not faithfully convert docbook tags like <code> and <package>, so
any option using such tags will not be converted at all.
Many options define their example to be a Nix value without using
literalExample. This sometimes gets rendered incorrectly in the manual,
causing confusion like in https://github.com/NixOS/nixpkgs/issues/25516
This fixes it by using literalExample for such options. The list of
option to fix was determined with this expression:
let
nixos = import ./nixos { configuration = {}; };
lib = import ./lib;
valid = d: {
# escapeNixIdentifier from https://github.com/NixOS/nixpkgs/pull/82461
set = lib.all (n: lib.strings.escapeNixIdentifier n == n) (lib.attrNames d) && lib.all (v: valid v) (lib.attrValues d);
list = lib.all (v: valid v) d;
}.${builtins.typeOf d} or true;
optionList = lib.optionAttrSetToDocList nixos.options;
in map (opt: {
file = lib.elemAt opt.declarations 0;
loc = lib.options.showOption opt.loc;
}) (lib.filter (opt: if opt ? example then ! valid opt.example else false) optionList)
which when evaluated will output all options that use a Nix identifier
that would need escaping as an attribute name.
