treewide: add defaultText for options using other shortcut bindings

nixos/modules/services/backup/tarsnap.nix

@@ -1,9 +1,10 @@
-{ config, lib, pkgs, utils, ... }:
+{ config, lib, options, pkgs, utils, ... }:
 
 with lib;
 
 let
   gcfg = config.services.tarsnap;
+  opt = options.services.tarsnap;
 
   configFile = name: cfg: ''
     keyfile ${cfg.keyfile}
@@ -65,6 +66,7 @@ in
               keyfile = mkOption {
                 type = types.str;
                 default = gcfg.keyfile;
+                defaultText = literalExpression "config.${opt.keyfile}";
                 description = ''
                   Set a specific keyfile for this archive. This defaults to
                   <literal>"/root/tarsnap.key"</literal> if left unspecified.

nixos/modules/services/monitoring/zabbix-proxy.nix

@@ -1,7 +1,8 @@
-{ config, lib, pkgs, ... }:
+{ config, lib, options, pkgs, ... }:
 
 let
   cfg = config.services.zabbixProxy;
+  opt = options.services.zabbixProxy;
   pgsql = config.services.postgresql;
   mysql = config.services.mysql;
 
@@ -103,6 +104,11 @@ in
         port = mkOption {
           type = types.int;
           default = if cfg.database.type == "mysql" then mysql.port else pgsql.port;
+          defaultText = literalExpression ''
+            if config.${opt.database.type} == "mysql"
+            then config.${options.services.mysql.port}
+            else config.${options.services.postgresql.port}
+          '';
           description = "Database host port.";
         };
 

nixos/modules/services/monitoring/zabbix-server.nix

@@ -1,7 +1,8 @@
-{ config, lib, pkgs, ... }:
+{ config, lib, options, pkgs, ... }:
 
 let
   cfg = config.services.zabbixServer;
+  opt = options.services.zabbixServer;
   pgsql = config.services.postgresql;
   mysql = config.services.mysql;
 
@@ -95,6 +96,11 @@ in
         port = mkOption {
           type = types.int;
           default = if cfg.database.type == "mysql" then mysql.port else pgsql.port;
+          defaultText = literalExpression ''
+            if config.${opt.database.type} == "mysql"
+            then config.${options.services.mysql.port}
+            else config.${options.services.postgresql.port}
+          '';
           description = "Database host port.";
         };
 

nixos/modules/services/web-apps/pgpkeyserver-lite.nix

@@ -1,4 +1,4 @@
-{ config, lib, pkgs, ... }:
+{ config, lib, options, pkgs, ... }:
 
 with lib;
 
@@ -6,6 +6,7 @@ let
 
   cfg = config.services.pgpkeyserver-lite;
   sksCfg = config.services.sks;
+  sksOpt = options.services.sks;
 
   webPkg = cfg.package;
 
@@ -37,6 +38,7 @@ in
 
       hkpAddress = mkOption {
         default = builtins.head sksCfg.hkpAddress;
+        defaultText = literalExpression "head config.${sksOpt.hkpAddress}";
         type = types.str;
         description = "
           Wich ip address the sks-keyserver is listening on.
@@ -45,6 +47,7 @@ in
 
       hkpPort = mkOption {
         default = sksCfg.hkpPort;
+        defaultText = literalExpression "config.${sksOpt.hkpPort}";
         type = types.int;
         description = "
           Which port the sks-keyserver is listening on.

nixos/modules/services/x11/display-managers/default.nix

@@ -148,6 +148,7 @@ in
       xauthBin = mkOption {
         internal = true;
         default = "${xorg.xauth}/bin/xauth";
+        defaultText = literalExpression ''"''${pkgs.xorg.xauth}/bin/xauth"'';
         description = "Path to the <command>xauth</command> program used by display managers.";
       };
 

nixos/modules/tasks/filesystems/zfs.nix

@@ -1,4 +1,4 @@
-{ config, lib, pkgs, utils, ... }:
+{ config, lib, options, pkgs, utils, ... }:
 #
 # TODO: zfs tunables
 
@@ -8,6 +8,7 @@ with lib;
 let
 
   cfgZfs = config.boot.zfs;
+  optZfs = options.boot.zfs;
   cfgExpandOnBoot = config.services.zfs.expandOnBoot;
   cfgSnapshots = config.services.zfs.autoSnapshot;
   cfgSnapFlags = cfgSnapshots.flags;
@@ -347,6 +348,7 @@ in
     services.zfs.zed = {
       enableMail = mkEnableOption "ZED's ability to send emails" // {
         default = cfgZfs.package.enableMail;
+        defaultText = literalExpression "config.${optZfs.package}.enableMail";
       };
 
       settings = mkOption {