Fix support for file extensions, due to off-by-1 error from not taking the period into account for the total suffix-length to pass to mkstemps.

Example failure:
template = myTempXXX.ext
pathExtension = "ext"
[pathExtension length] = 3

Need for mkstemps:
suffix-length = 4 (".ext")

DELTA=6 (5 added, 0 deleted, 1 changed)
DELTA_BY_EXTENSION=m=6

1 files changed, 6 insertions, 1 deletions

diff --git a/Foundation/GTMNSFileHandle+UniqueName.m b/Foundation/GTMNSFileHandle+UniqueName.m
index 536e154..d373159 100644
--- a/Foundation/GTMNSFileHandle+UniqueName.m
+++ b/Foundation/GTMNSFileHandle+UniqueName.m
@@ -28,7 +28,12 @@
   NSString *extension = [pathTemplate pathExtension];
   char *pathTemplateCString = strdup([pathTemplate fileSystemRepresentation]);
   if (!pathTemplateCString) return nil;
-  int fileDescriptor = mkstemps(pathTemplateCString, (int)[extension length]);
+  int len = (int)[extension length];
+  if (len > 0) {
+    // Suffix length needs to include a period.
+    len++;
+  }
+  int fileDescriptor = mkstemps(pathTemplateCString, len);
   if (fileDescriptor == -1) {
     free(pathTemplateCString);
     return nil;