diff --git a/Lib/sre_compile.py b/Lib/sre_compile.py
index 7cda2b6..15d2324 100644
--- a/Lib/sre_compile.py
+++ b/Lib/sre_compile.py
@@ -355,8 +355,6 @@ def _optimize_unicode(charset, fixup):
def _simple(av):
# check if av is a "simple" operator
lo, hi = av[2].getwidth()
- if lo == 0 and hi == MAXREPEAT:
- raise error, "nothing to repeat"
return lo == hi == 1 and av[2][0][0] != SUBPATTERN
def _compile_info(code, pattern, flags):
diff --git a/Lib/sre_parse.py b/Lib/sre_parse.py
index 75f8c96..644441d 100644
--- a/Lib/sre_parse.py
+++ b/Lib/sre_parse.py
@@ -147,7 +147,7 @@ class SubPattern:
REPEATCODES = (MIN_REPEAT, MAX_REPEAT)
for op, av in self.data:
if op is BRANCH:
- i = sys.maxint
+ i = MAXREPEAT - 1
j = 0
for av in av[1]:
l, h = av.getwidth()
@@ -165,14 +165,14 @@ class SubPattern:
hi = hi + j
elif op in REPEATCODES:
i, j = av[2].getwidth()
- lo = lo + long(i) * av[0]
- hi = hi + long(j) * av[1]
+ lo = lo + i * av[0]
+ hi = hi + j * av[1]
elif op in UNITCODES:
lo = lo + 1
hi = hi + 1
elif op == SUCCESS:
break
- self.width = int(min(lo, sys.maxint)), int(min(hi, sys.maxint))
+ self.width = min(lo, MAXREPEAT - 1), min(hi, MAXREPEAT)
return self.width
class Tokenizer:
diff --git a/Lib/test/test_re.py b/Lib/test/test_re.py
index 18a81a2..f0827d8 100644
--- a/Lib/test/test_re.py
+++ b/Lib/test/test_re.py
@@ -897,6 +897,17 @@ class ReTests(unittest.TestCase):
with self.assertRaisesRegexp(sre_constants.error, '\?foo'):
re.compile('(?P<?foo>)')
+ def test_bug_2537(self):
+ # issue 2537: empty submatches
+ for outer_op in ('{0,}', '*', '+', '{1,187}'):
+ for inner_op in ('{0,}', '*', '?'):
+ r = re.compile("^((x|y)%s)%s" % (inner_op, outer_op))
+ m = r.match("xyyzy")
+ self.assertEqual(m.group(0), "xyy")
+ self.assertEqual(m.group(1), "")
+ self.assertEqual(m.group(2), "y")
+
+
def run_re_tests():
from test.re_tests import tests, SUCCEED, FAIL, SYNTAX_ERROR
diff --git a/Lib/doctest.py b/Lib/doctest.py
index 90bcca1..0ee40a2 100644
--- a/Lib/doctest.py
+++ b/Lib/doctest.py
@@ -564,7 +564,7 @@ class DocTestParser:
# Want consists of any non-blank lines that do not start with PS1.
(?P<want> (?:(?![ ]*$) # Not a blank line
(?![ ]*>>>) # Not a line starting with PS1
- .*$\n? # But any other line
+ .+$\n? # But any other line
)*)
''', re.MULTILINE | re.VERBOSE)