ci/treefmt: add markdown-code-runner (#427460)

Author: wolfgangwalther

ci/default.nix

@@ -75,6 +75,23 @@ let
           includes = [ "*" ];
           priority = 1;
         };
+
+        # TODO: Upstream this into treefmt-nix eventually:
+        #   https://github.com/numtide/treefmt-nix/issues/387
+        settings.formatter.markdown-code-runner = {
+          command = pkgs.lib.getExe pkgs.markdown-code-runner;
+          options =
+            let
+              config = pkgs.writers.writeTOML "markdown-code-runner-config" {
+                presets.nixfmt = {
+                  language = "nix";
+                  command = [ (pkgs.lib.getExe pkgs.nixfmt) ];
+                };
+              };
+            in
+            [ "--config=${config}" ];
+          includes = [ "*.md" ];
+        };
       };
       fs = pkgs.lib.fileset;
       nixFilesSrc = fs.toSource {

doc/doc-support/package.nix

@@ -137,7 +137,6 @@ stdenvNoCC.mkDerivation (
 
       tests = {
         manpage-urls = callPackage ../tests/manpage-urls.nix { };
-        check-nix-code-blocks = callPackage ../tests/check-nix-code-blocks.nix { };
       };
     };
   }

doc/tests/check-nix-code-blocks.nix

@@ -45,11 +45,18 @@ So note that the default value of `system.services.<name>` is not a complete ser
 It is possible to write service modules that are portable. This is done by either avoiding the `systemd` option tree, or by defining process-manager-specific definitions in an optional way:
 
 ```nix
-{ config, options, lib, ... }: {
+{
+  config,
+  options,
+  lib,
+  ...
+}:
+{
   _class = "service";
   config = {
     process.argv = [ (lib.getExe config.foo.program) ];
-  } // lib.optionalAttrs (options?systemd) {
+  }
+  // lib.optionalAttrs (options ? systemd) {
     # ... systemd-specific definitions ...
   };
 }

doc/tests/mdcr-config.toml

@@ -19,8 +19,8 @@ For a basic configuration with Postfix as the MTA, the following settings are su
       local_recipient_maps = [ "hash:/var/lib/mailman/data/postfix_lmtp" ];
       relay_domains = [ "hash:/var/lib/mailman/data/postfix_domains" ];
       smtpd_tls_chain_files = [
-        config.security.acme.certs."lists.example.org".directory + "/full.pem"
-        config.security.acme.certs."lists.example.org".directory + "/key.pem"
+        (config.security.acme.certs."lists.example.org".directory + "/full.pem")
+        (config.security.acme.certs."lists.example.org".directory + "/key.pem")
       ];
     };
   };