Handle

2 files changed, 5 insertions, 2 deletions

diff --git a/pycodestyle.py b/pycodestyle.py
index b1fb8a7..d9682b8 100755
--- a/pycodestyle.py
+++ b/pycodestyle.py
@@ -140,8 +140,8 @@ EXTRANEOUS_WHITESPACE_REGEX = re.compile(r'[\[({] | [\]}),;]| :(?!=)')
 WHITESPACE_AFTER_COMMA_REGEX = re.compile(r'[,;:]\s*(?:  |\t)')
 COMPARE_SINGLETON_REGEX = re.compile(r'(\bNone|\bFalse|\bTrue)?\s*([=!]=)'
                                      r'\s*(?(1)|(None|False|True))\b')
-COMPARE_NEGATIVE_REGEX = re.compile(r'\b(not)\s+[^][)(}{ ]+\s+(in|is)'
-                                    r'\s+(?!not\s)')
+COMPARE_NEGATIVE_REGEX = re.compile(r'\b(?<!is\s)(not)\s+[^][)(}{ ]+\s+'
+                                    r'(in|is)\s')
 COMPARE_TYPE_REGEX = re.compile(r'(?:[=!]=|is(?:\s+not)?)\s+type(?:s.\w+Type'
                                 r'|\s*\(\s*([^)]*[^ )])\s*\))')
 KEYWORD_REGEX = re.compile(r'(\s*)\b(?:%s)\b(\s*)' % r'|'.join(KEYWORDS))
diff --git a/testsuite/E71.py b/testsuite/E71.py
index e7f8869..abf4e7a 100644
--- a/testsuite/E71.py
+++ b/testsuite/E71.py
@@ -67,6 +67,9 @@ if not X.B is Y:
 #: E714
 if not X is Y is not Z:
     pass
+#: E714
+if not X is not Y:
+    pass
 
 #
 #: Okay