bpo-36272: Logging now propagates RecursionError (GH-12312)

Author: Rémi Lapeyre

Lib/logging/__init__.py

@@ -1032,6 +1032,8 @@ def handleError(self, record):
                     sys.stderr.write('Message: %r\n'
                                      'Arguments: %s\n' % (record.msg,
                                                           record.args))
+                except RecursionError:  # See issue 36272
+                    raise
                 except Exception:
                     sys.stderr.write('Unable to print the message and arguments'
                                      ' - possible formatting error.\nUse the'
@@ -1094,6 +1096,8 @@ def emit(self, record):
             # issue 35046: merged two stream.writes into one.
             stream.write(msg + self.terminator)
             self.flush()
+        except RecursionError:  # See issue 36272
+            raise
         except Exception:
             self.handleError(record)
 

Lib/test/test_logging.py

@@ -41,7 +41,7 @@
 import struct
 import sys
 import tempfile
-from test.support.script_helper import assert_python_ok
+from test.support.script_helper import assert_python_ok, assert_python_failure
 from test import support
 import textwrap
 import threading
@@ -4142,6 +4142,21 @@ def __del__(self):
         self.assertIn("exception in __del__", err)
         self.assertIn("ValueError: some error", err)
 
+    def test_recursion_error(self):
+        # Issue 36272
+        code = """if 1:
+            import logging
+
+            def rec():
+                logging.error("foo")
+                rec()
+
+            rec()"""
+        rc, out, err = assert_python_failure("-c", code)
+        err = err.decode()
+        self.assertNotIn("Cannot recover from stack overflow.", err)
+        self.assertEqual(rc, 1)
+
 
 class LogRecordTest(BaseTest):
     def test_str_rep(self):

Misc/NEWS.d/next/Library/2019-03-13-14-14-36.bpo-36272.f3l2IG.rst

@@ -0,0 +1,2 @@
+:mod:`logging` does not silently ignore RecursionError anymore. Patch
+contributed by Rémi Lapeyre.