From a6bb468acf48e2dd9dddbd54d911f9e5919b70a3 Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <edolstra@gmail.com>
Date: Mon, 21 Nov 2016 14:51:57 +0100
Subject: [PATCH] mkIf: Check whether the condition is a Boolean
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
This gives a nicer error message than (say)
while evaluating the option `fileSystems':
while evaluating the attribute ‘isDefined’ at /nix/store/r8z4vvl2qzg31zm4ra6awlx5b22k7gf9-nixos-16.09.tar.gz/lib/modules.nix:323:5:
while evaluating ‘filterOverrides’ at /nix/store/r8z4vvl2qzg31zm4ra6awlx5b22k7gf9-nixos-16.09.tar.gz/lib/modules.nix:395:21, called from /nix/store/r8z4vvl2qzg31zm4ra6awlx5b22k7gf9-nixos-16.09.tar.gz/lib/modules.nix:307:18:
while evaluating ‘concatMap’ at /nix/store/r8z4vvl2qzg31zm4ra6awlx5b22k7gf9-nixos-16.09.tar.gz/lib/lists.nix:79:18, called from /nix/store/r8z4vvl2qzg31zm4ra6awlx5b22k7gf9-nixos-16.09.tar.gz/lib/modules.nix:401:8:
while evaluating ‘concatMap’ at /nix/store/r8z4vvl2qzg31zm4ra6awlx5b22k7gf9-nixos-16.09.tar.gz/lib/lists.nix:79:18, called from /nix/store/r8z4vvl2qzg31zm4ra6awlx5b22k7gf9-nixos-16.09.tar.gz/lib/modules.nix:302:17:
while evaluating anonymous function at /nix/store/r8z4vvl2qzg31zm4ra6awlx5b22k7gf9-nixos-16.09.tar.gz/lib/modules.nix:302:28, called from undefined position:
while evaluating ‘dischargeProperties’ at /nix/store/r8z4vvl2qzg31zm4ra6awlx5b22k7gf9-nixos-16.09.tar.gz/lib/modules.nix:365:25, called from /nix/store/r8z4vvl2qzg31zm4ra6awlx5b22k7gf9-nixos-16.09.tar.gz/lib/modules.nix:303:62:
value is a list while a Boolean was expected
---
lib/modules.nix | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/lib/modules.nix b/lib/modules.nix
index e66d6a6926cb..256d49ba27d8 100644
--- a/lib/modules.nix
+++ b/lib/modules.nix
@@ -375,10 +375,13 @@ rec {
if def._type or "" == "merge" then
concatMap dischargeProperties def.contents
else if def._type or "" == "if" then
- if def.condition then
- dischargeProperties def.content
+ if isBool def.condition then
+ if def.condition then
+ dischargeProperties def.content
+ else
+ [ ]
else
- [ ]
+ throw "‘mkIf’ called with a non-Boolean condition"
else
[ def ];