From 3572f89bbe154087d8ad83c36674d0c2499c0967 Mon Sep 17 00:00:00 2001
From: Daiderd Jordan <daiderd@gmail.com>
Date: Sat, 21 Jul 2018 12:26:53 +0200
Subject: [PATCH] ssh: don't add empty PubkeyAcceptedKeyTypes/HostKeyAlgorithms

The options introduced in e2444a433fb would generate a broken
ssh config when set to an empty list.

/etc/ssh/ssh_config line 7: Missing argument.
---
 nixos/modules/programs/ssh.nix | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/nixos/modules/programs/ssh.nix b/nixos/modules/programs/ssh.nix
index db44f9040dde..0f7f0515f0e9 100644
--- a/nixos/modules/programs/ssh.nix
+++ b/nixos/modules/programs/ssh.nix
@@ -211,8 +211,8 @@ in
 
         ForwardX11 ${if cfg.forwardX11 then "yes" else "no"}
 
-        PubkeyAcceptedKeyTypes ${concatStringsSep "," cfg.pubkeyAcceptedKeyTypes}
-        HostKeyAlgorithms ${concatStringsSep "," cfg.hostKeyAlgorithms}
+        ${optionalString (cfg.pubkeyAcceptedKeyTypes != []) PubkeyAcceptedKeyTypes "${concatStringsSep "," cfg.pubkeyAcceptedKeyTypes}"}
+        ${optionalString (cfg.hostKeyAlgorithms != []) HostKeyAlgorithms "${concatStringsSep "," cfg.hostKeyAlgorithms}"}
 
         ${cfg.extraConfig}
       '';