diff options
Diffstat (limited to 'Lib/site.py')
| -rw-r--r-- | Lib/site.py | 39 |
1 files changed, 29 insertions, 10 deletions
diff --git a/Lib/site.py b/Lib/site.py index 96a4bef..08b98eb 100644 --- a/Lib/site.py +++ b/Lib/site.py @@ -68,6 +68,7 @@ site-specific customizations. If this import fails with an ImportError exception, it is silently ignored. """ +import atexit import sys import os import re @@ -86,6 +87,25 @@ USER_SITE = None USER_BASE = None +_no_builtin = object() + +def _patch_builtins(**items): + # When patching builtins, we make some objects almost immortal + # (builtins are only reclaimed at the very end of the interpreter + # shutdown sequence). To avoid keeping to many references alive, + # we register callbacks to undo our builtins additions. + old_items = {k: getattr(builtins, k, _no_builtin) for k in items} + def unpatch(old_items=old_items): + for k, v in old_items.items(): + if v is _no_builtin: + delattr(builtins, k) + else: + setattr(builtins, k, v) + for k, v in items.items(): + setattr(builtins, k, v) + atexit.register(unpatch) + + def makepath(*paths): dir = os.path.join(*paths) try: @@ -357,8 +377,7 @@ def setquit(): except: pass raise SystemExit(code) - builtins.quit = Quitter('quit') - builtins.exit = Quitter('exit') + _patch_builtins(quit=Quitter('quit'), exit=Quitter('exit')) class _Printer(object): @@ -423,20 +442,20 @@ class _Printer(object): def setcopyright(): """Set 'copyright' and 'credits' in builtins""" - builtins.copyright = _Printer("copyright", sys.copyright) + _patch_builtins(copyright=_Printer("copyright", sys.copyright)) if sys.platform[:4] == 'java': - builtins.credits = _Printer( + _patch_builtins(credits=_Printer( "credits", - "Jython is maintained by the Jython developers (www.jython.org).") + "Jython is maintained by the Jython developers (www.jython.org).")) else: - builtins.credits = _Printer("credits", """\ + _patch_builtins(credits=_Printer("credits", """\ Thanks to CWI, CNRI, BeOpen.com, Zope Corporation and a cast of thousands - for supporting Python development. See www.python.org for more information.""") + for supporting Python development. See www.python.org for more information.""")) here = os.path.dirname(os.__file__) - builtins.license = _Printer( + _patch_builtins(license=_Printer( "license", "See http://www.python.org/%.3s/license.html" % sys.version, ["LICENSE.txt", "LICENSE"], - [os.path.join(here, os.pardir), here, os.curdir]) + [os.path.join(here, os.pardir), here, os.curdir])) class _Helper(object): @@ -453,7 +472,7 @@ class _Helper(object): return pydoc.help(*args, **kwds) def sethelper(): - builtins.help = _Helper() + _patch_builtins(help=_Helper()) def enablerlcompleter(): """Enable default readline configuration on interactive prompts, by |