an SRE bugfix a day keeps Guido away...
#462270: sub-tle difference between pre.sub and sre.sub. PRE ignored
an empty match at the previous location, SRE didn't.
also synced with Secret Labs "sreopen" codebase.
diff --git a/Lib/sre.py b/Lib/sre.py
index eb8325d..a87870e 100644
--- a/Lib/sre.py
+++ b/Lib/sre.py
@@ -45,7 +45,7 @@
"|" A|B, creates an RE that will match either A or B.
(...) Matches the RE inside the parentheses.
The contents can be retrieved or matched later in the string.
- (?iLmsx) Set the I, L, M, S, or X flag for the RE.
+ (?iLmsx) Set the I, L, M, S, or X flag for the RE (see below).
(?:...) Non-grouping version of regular parentheses.
(?P<name>...) The substring matched by the group is accessible by name.
(?P=name) Matches the text matched earlier by the group named name.
@@ -80,7 +80,6 @@
findall Find all occurrences of a pattern in a string.
compile Compile a pattern into a RegexObject.
purge Clear the regular expression cache.
- template Compile a template pattern, returning a pattern object.
escape Backslash all non-alphanumerics in a string.
Some of the functions in this module takes flags as optional parameters:
@@ -90,11 +89,12 @@
"$" matches the end of lines as well as the string.
S DOTALL "." matches any character at all, including the newline.
X VERBOSE Ignore whitespace and comments for nicer looking RE's.
- U UNICODE Use unicode locale.
+ U UNICODE Make \w, \W, \b, \B, dependent on the Unicode locale.
This module also defines an exception 'error'.
"""
+
import sre_compile
import sre_parse
@@ -104,7 +104,7 @@
"U", "IGNORECASE", "LOCALE", "MULTILINE", "DOTALL", "VERBOSE",
"UNICODE", "error" ]
-__version__ = "2.1b2"
+__version__ = "2.1.1"
# this module works under 1.5.2 and later. don't use string methods
import string
@@ -269,6 +269,9 @@
b, e = m.span()
if i < b:
append(text[i:b])
+ elif i == b == e and n:
+ append(text[i:b])
+ continue # ignore empty match at previous position
append(filter(m))
i = e
n = n + 1
diff --git a/Lib/test/test_sre.py b/Lib/test/test_sre.py
index 8442258..49fe4c6 100644
--- a/Lib/test/test_sre.py
+++ b/Lib/test/test_sre.py
@@ -123,6 +123,10 @@
test(r"""sre.sub(r'\r\n', '\n', 'abc\r\ndef\r\n')""", 'abc\ndef\n')
test(r"""sre.sub('\r\n', '\n', 'abc\r\ndef\r\n')""", 'abc\ndef\n')
+# Test for empty sub() behaviour, see SF bug #462270
+test(r"""sre.sub('x*', '-', 'abxd')""", '-a-b-d-')
+test(r"""sre.sub('x+', '-', 'abxd')""", 'ab-d')
+
if verbose:
print 'Running tests on symbolic references'