From: Tim Peters <tim.peters@gmail.com>
Date: Wed, 10 May 2006 02:46:48 +0000 (+0000)
Subject: Merge rev 45944 from trunk.
X-Git-Tag: v2.4.4c1~228
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=38e726d7da3ae47343acdd90eb34635201f96095;p=thirdparty%2FPython%2Fcpython.git

Merge rev 45944 from trunk.

Variant of patch #1478292.  doctest.register_optionflag(name)
shouldn't create a new flag when `name` is already the name of
an option flag.
---

diff --git a/Lib/doctest.py b/Lib/doctest.py
index 642b5223b906..d146a83459d5 100644
--- a/Lib/doctest.py
+++ b/Lib/doctest.py
@@ -128,9 +128,8 @@ warnings.filterwarnings("ignore", "is_private", DeprecationWarning,
 
 OPTIONFLAGS_BY_NAME = {}
 def register_optionflag(name):
-    flag = 1 << len(OPTIONFLAGS_BY_NAME)
-    OPTIONFLAGS_BY_NAME[name] = flag
-    return flag
+    # Create a new flag unless `name` is already known.
+    return OPTIONFLAGS_BY_NAME.setdefault(name, 1 << len(OPTIONFLAGS_BY_NAME))
 
 DONT_ACCEPT_TRUE_FOR_1 = register_optionflag('DONT_ACCEPT_TRUE_FOR_1')
 DONT_ACCEPT_BLANKLINE = register_optionflag('DONT_ACCEPT_BLANKLINE')
diff --git a/Lib/test/test_doctest.py b/Lib/test/test_doctest.py
index 1665c05414e2..36ffec906f99 100644
--- a/Lib/test/test_doctest.py
+++ b/Lib/test/test_doctest.py
@@ -1281,6 +1281,26 @@ count as failures:
         ValueError: 2
     (3, 5)
 
+New option flags can also be registered, via register_optionflag().  Here
+we reach into doctest's internals a bit.
+
+    >>> unlikely = "UNLIKELY_OPTION_NAME"
+    >>> unlikely in doctest.OPTIONFLAGS_BY_NAME
+    False
+    >>> new_flag_value = doctest.register_optionflag(unlikely)
+    >>> unlikely in doctest.OPTIONFLAGS_BY_NAME
+    True
+
+Before 2.4.4/2.5, registering a name more than once erroneously created
+more than one flag value.  Here we verify that's fixed:
+
+    >>> redundant_flag_value = doctest.register_optionflag(unlikely)
+    >>> redundant_flag_value == new_flag_value
+    True
+
+Clean up.
+    >>> del doctest.OPTIONFLAGS_BY_NAME[unlikely]
+
     """
 
     def option_directives(): r"""
diff --git a/Misc/NEWS b/Misc/NEWS
index 593a881df604..5adfc1178741 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -32,6 +32,9 @@ Extension Modules
 Library
 -------
 
+- Patch #1478292. ``doctest.register_optionflag(name)`` shouldn't create a
+  new flag when ``name`` is already the name of an option flag.
+
 - Bug #1473760: ``tempfile.TemporaryFile()`` could hang on Windows, when
   called from a thread spawned as a side effect of importing a module.