[Piglit] [RFC 04/10] framework: fix grouptools.commonprefix when len(args) == 1

[Nicolai Hähnle]

From: Nicolai Hähnle <nicolai.haehnle at amd.com>

---
 framework/grouptools.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/framework/grouptools.py b/framework/grouptools.py
index 2ee74ed9f..1a65c0dcd 100644
--- a/framework/grouptools.py
+++ b/framework/grouptools.py
@@ -82,21 +82,21 @@ def splitname(group):
     i = group.rfind(SEPARATOR) + 1
     head, tail = group[:i], group[i:]
     head = head.rstrip(SEPARATOR)
 
     return head, tail
 
 
 def commonprefix(args):
     """Given a list of groups, returns the longest common leading component."""
     if len(args) == 1:
-        return args
+        return args[0]
     elif any(e == '' for e in args):
         return ''
 
     common = []
 
     for elems in zip(*[split(a) for a in args]):
         iter_ = iter(elems)
         first = next(iter_)
         if all(first == r for r in iter_):
             common.append(first)
-- 
2.11.0