Fix tests with an empty NPTest.cache file

The NPTest.cache cannot be loaded when empty, and this prevents
getting the data and populating the file. This patch skips the file when
empty as if it didn't exist.

1 files changed, 1 insertions, 1 deletions

diff --git a/NPTest.pm b/NPTest.pm
index b00a708..3d6e3a2 100644
--- a/NPTest.pm
+++ b/NPTest.pm
@@ -438,7 +438,7 @@ sub LoadCache
 
     chomp($fileContents);
     my( $contentsRef ) = eval $fileContents;
-    %CACHE = %{$contentsRef};
+    %CACHE = %{$contentsRef} if (defined($contentsRef));
 
   }