From 91eb6cf82cc7fa2eaa2802f64a15ab75be726fae Mon Sep 17 00:00:00 2001
From: Joerg Thalheim <joerg@thalheim.io>
Date: Thu, 28 Sep 2017 10:47:19 +0100
Subject: [PATCH] nullmailer: simplify config generation

---
 nixos/modules/services/mail/nullmailer.nix | 14 +++-----------
 1 file changed, 3 insertions(+), 11 deletions(-)

diff --git a/nixos/modules/services/mail/nullmailer.nix b/nixos/modules/services/mail/nullmailer.nix
index c5af1d4d381..59cb512c115 100644
--- a/nixos/modules/services/mail/nullmailer.nix
+++ b/nixos/modules/services/mail/nullmailer.nix
@@ -194,18 +194,10 @@ with lib;
     environment = {
       systemPackages = [ pkgs.nullmailer ];
       etc = let
-        getval  = attr: builtins.getAttr attr cfg.config;
-        attrs   = builtins.attrNames cfg.config;
-        remotesFilter = if cfg.remotesFile != null
-                        then (attr: attr != "remotes")
-                        else (_: true);
-        optionalRemotesFileLink = if cfg.remotesFile != null
-                                  then { "nullmailer/remotes".source = cfg.remotesFile; }
-                                  else {};
-        attrs'  = builtins.filter (attr: (! isNull (getval attr)) && (remotesFilter attr)) attrs;
+        validAttrs = filterAttrs (name: value: value != null) cfg.config;
       in
-        (foldl' (as: attr: as // { "nullmailer/${attr}".text = getval attr; }) {} attrs')
-        // optionalRemotesFileLink;
+        (foldl' (as: name: as // { "nullmailer/${name}".text = validAttrs.${name}; }) {} (attrNames validAttrs))
+          // optionalAttrs (cfg.remotesFile != null) { "nullmailer/remotes".source = cfg.remotesFile; };
     };
 
     users = {