``zc.buildout.testing.buildoutSetUp`` installs a new handler in the python...

``zc.buildout.testing.buildoutSetUp`` installs a new handler in the python root logging facility. This handler is now removed during tear down as it might disturb other packages reusing buildout's testing infrastructure.

CHANGES.txt

@@ -5,9 +5,16 @@ Change History
 ==================
 
 - Better Windows compatibility in test infrastructure.
+
 - Now the bootstrap.py has an optional --version argument,
   that can be used to force zc.buildout version to use.
 
+- ``zc.buildout.testing.buildoutSetUp`` installs a new handler in the
+  python root logging facility. This handler is now removed during
+  tear down as it might disturb other packages reusing buildout's
+  testing infrastructure.
+
+
 1.2.1 (2009-03-18)
 ==================
 

src/zc/buildout/testing.py

@@ -18,6 +18,7 @@ $Id$
 
 import BaseHTTPServer
 import errno
+import logging
 import os
 import pkg_resources
 import random
@@ -210,6 +211,14 @@ def buildoutSetUp(test):
     here = os.getcwd()
     register_teardown(lambda: os.chdir(here))
 
+    handlers_before_set_up = logging.getLogger().handlers[:]
+    def restore_root_logger_handlers():
+        root_logger = logging.getLogger()
+        for handler in root_logger.handlers[:]:
+            root_logger.removeHandler(handler)
+        for handler in handlers_before_set_up:
+            root_logger.addHandler(handler)
+    register_teardown(restore_root_logger_handlers)
 
     base = tempfile.mkdtemp('buildoutSetUp')
     base = os.path.realpath(base)

src/zc/buildout/testing_bugfix.txt

+Bug fixes in zc.buildout.testing
+================================
+
+Logging handler which did not get deleted
+-----------------------------------------
+
+The buildout testing set up runs a buildout which adds a
+``logging.StreamHandler`` to the root logger. But tear down did not
+remove it. This can disturb other tests of packages reusing
+zc.buildout.testing.
+
+The handers before calling set up are:
+
+    >>> import logging
+    >>> len(logging.getLogger().handlers)
+    1
+    >>> logging.getLogger().handlers # doctest: +ELLIPSIS
+    [<zope.testing.testrunner.logsupport.NullHandler instance at ...>]
+
+After calling it, a ``logging.StreamHandler`` was added:
+
+    >>> import zc.buildout.testing
+    >>> import doctest
+    >>> test = doctest.DocTestParser().get_doctest(
+    ...     '>>> x', {}, 'foo', 'foo.py', 0)
+    >>> zc.buildout.testing.buildoutSetUp(test)
+    >>> len(logging.getLogger().handlers)
+    2
+    >>> logging.getLogger().handlers # doctest: +ELLIPSIS +NORMALIZE_WHITESPACE
+    [<zope.testing.testrunner.logsupport.NullHandler instance at ...>,
+     <logging.StreamHandler instance at ...>]
+
+But tear down removes the new logging handler:
+
+    >>> zc.buildout.testing.buildoutTearDown(test)
+    >>> len(logging.getLogger().handlers)
+    1
+    >>> logging.getLogger().handlers # doctest: +ELLIPSIS
+    [<zope.testing.testrunner.logsupport.NullHandler instance at ...>]