From 8b3a0b28ba2d62a90d15700540c30111f412d8a9 Mon Sep 17 00:00:00 2001
From: Peter Krempa <pkrempa@redhat.com>
Date: Fri, 28 Jul 2017 12:37:48 +0200
Subject: [PATCH] tests: utils: Allow NULL strings to be equal to empty file in
 virTestCompareToFile

Treat an NULL string equivalent to an empty string in
virTestCompareToFile so that callers don't need to add additional logic
in case when a test produces no output.
---
 tests/testutils.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/tests/testutils.c b/tests/testutils.c
index 40e9650fdd..71692f1fa5 100644
--- a/tests/testutils.c
+++ b/tests/testutils.c
@@ -777,6 +777,8 @@ int virTestDifferenceBin(FILE *stream,
 /*
  * @param strcontent: String input content
  * @param filename: File to compare strcontent against
+ *
+ * If @strcontent is NULL, it's treated as an empty string.
  */
 int
 virTestCompareToFile(const char *strcontent,
@@ -787,6 +789,9 @@ virTestCompareToFile(const char *strcontent,
     char *fixedcontent = NULL;
     const char *cmpcontent = strcontent;
 
+    if (!cmpcontent)
+        cmpcontent = "";
+
     if (virTestLoadFile(filename, &filecontent) < 0 && !virTestGetRegenerate())
         goto failure;