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.

diff --git a/tests/testutils.c b/tests/testutils.c
index 40e9650fdd3ca8bc14c0d405dd81a6d4c37b7a1c..71692f1fa56316145d1fc4cd1461f5231a920aeb 100644 (file)
--- 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;