From 9bb798c18b33bd31259722d95a2e98b11ec6006d Mon Sep 17 00:00:00 2001
From: "Alexander A. Klimov" <alexander.klimov@netways.de>
Date: Wed, 12 Oct 2016 11:06:04 +0200
Subject: [PATCH] IniWriter: don't persist a section key if the value is null

refs #11743
---
 library/Icinga/File/Ini/IniWriter.php | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/library/Icinga/File/Ini/IniWriter.php b/library/Icinga/File/Ini/IniWriter.php
index 83410599f..f00040e39 100644
--- a/library/Icinga/File/Ini/IniWriter.php
+++ b/library/Icinga/File/Ini/IniWriter.php
@@ -149,6 +149,10 @@ class IniWriter
                 $domSection = $doc->getSection($section);
             }
             foreach ($directives as $key => $value) {
+                if ($value === null) {
+                    continue;
+                }
+
                 if ($value instanceof ConfigObject) {
                     throw new ProgrammingError('Cannot diff recursive configs');
                 }