Issue #20426: When passing the re.DEBUG flag, re.compile() displays the debug output every time it is called, regardless of the compilation cache.
diff --git a/Lib/test/test_re.py b/Lib/test/test_re.py
index 7ebbf05..fe71c84 100644
--- a/Lib/test/test_re.py
+++ b/Lib/test/test_re.py
@@ -1,5 +1,6 @@
from test.test_support import verbose, run_unittest, import_module
from test.test_support import precisionbigmemtest, _2G, cpython_only
+from test.test_support import captured_stdout
import re
from re import Scanner
import sre_constants
@@ -920,6 +921,19 @@
self.assertEqual(m.group(1), "")
self.assertEqual(m.group(2), "y")
+ def test_debug_flag(self):
+ with captured_stdout() as out:
+ re.compile('foo', re.DEBUG)
+ self.assertEqual(out.getvalue().splitlines(),
+ ['literal 102', 'literal 111', 'literal 111'])
+ # Debug output is output again even a second time (bypassing
+ # the cache -- issue #20426).
+ with captured_stdout() as out:
+ re.compile('foo', re.DEBUG)
+ self.assertEqual(out.getvalue().splitlines(),
+ ['literal 102', 'literal 111', 'literal 111'])
+
+
def run_re_tests():
from test.re_tests import tests, SUCCEED, FAIL, SYNTAX_ERROR
if verbose: