Make _strptime escape regex syntax in format string to prevent use in internal regex.
diff --git a/Lib/_strptime.py b/Lib/_strptime.py
index 55391c1..0777b7e 100644
--- a/Lib/_strptime.py
+++ b/Lib/_strptime.py
@@ -373,8 +373,17 @@
return '%s)' % regex
def pattern(self, format):
- """Return re pattern for the format string."""
+ """Return re pattern for the format string.
+
+ Need to make sure that any characters that might be interpreted as
+ regex syntax is escaped.
+
+ """
processed_format = ''
+ # The sub() call escapes all characters that might be misconstrued
+ # as regex syntax.
+ regex_chars = re_compile(r"([\\.^$*+?{}\[\]|])")
+ format = regex_chars.sub(r"\\\1", format)
whitespace_replacement = re_compile('\s+')
format = whitespace_replacement.sub('\s*', format)
while format.find('%') != -1: