From: Martin Krizek <martin.krizek@gmail.com>
Date: Wed, 17 Jan 2018 22:09:23 +0000 (+0100)
Subject: Don't check for generator if not needed
X-Git-Tag: 2.11.0~128^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=refs%2Fpull%2F799%2Fhead;p=thirdparty%2Fjinja.git

Don't check for generator if not needed
---

diff --git a/jinja2/nativetypes.py b/jinja2/nativetypes.py
index fcfeddfe..31309bca 100644
--- a/jinja2/nativetypes.py
+++ b/jinja2/nativetypes.py
@@ -21,12 +21,11 @@ def native_concat(nodes):
     if not head:
         return None
 
-    if isinstance(nodes, types.GeneratorType):
-        nodes = chain(head, nodes)
-
     if len(head) == 1:
         out = head[0]
     else:
+        if isinstance(nodes, types.GeneratorType):
+            nodes = chain(head, nodes)
         out = u''.join([text_type(v) for v in nodes])
 
     try: