1 files changed, 64 insertions, 1 deletions
diff --git a/nose/pyversion.py b/nose/pyversion.py
index a6ec3f7..07c105f 100644
--- a/nose/pyversion.py
+++ b/nose/pyversion.py
@@ -3,19 +3,33 @@ This module contains fixups for using nose under different versions of Python.
 """
 import sys
 import os
+import traceback
 import types
 import inspect
 import nose.util
 
 __all__ = ['make_instancemethod', 'cmp_to_key', 'sort_list', 'ClassType',
            'TypeType', 'UNICODE_STRINGS', 'unbound_method', 'ismethod',
-           'bytes_']
+           'bytes_', 'is_base_exception', 'force_unicode', 'exc_to_unicode',
+           'format_exception']
 
 # In Python 3.x, all strings are unicode (the call to 'unicode()' in the 2.x
 # source will be replaced with 'str()' when running 2to3, so this test will
 # then become true)
 UNICODE_STRINGS = (type(unicode()) == type(str()))
 
+if sys.version_info[:2] < (3, 0):
+    def force_unicode(s, encoding='UTF-8'):
+        try:
+            s = unicode(s)
+        except UnicodeDecodeError:
+            s = str(s).decode(encoding, 'replace')
+
+        return s
+else:
+    def force_unicode(s, encoding='UTF-8'):
+        return str(s)
+
 # new.instancemethod() is obsolete for new-style classes (Python 3.x)
 # We need to use descriptor methods instead.
 try:
@@ -147,3 +161,52 @@ else:
             return func.func_code.co_flags & CO_GENERATOR != 0
         except AttributeError:
             return False
+
+# Make a function to help check if an exception is derived from BaseException.
+# In Python 2.4, we just use Exception instead.
+if sys.version_info[:2] < (2, 5):
+    def is_base_exception(exc):
+        return isinstance(exc, Exception)
+else:
+    def is_base_exception(exc):
+        return isinstance(exc, BaseException)
+
+if sys.version_info[:2] < (3, 0):
+    def exc_to_unicode(ev, encoding='utf-8'):
+        if is_base_exception(ev):
+            if not hasattr(ev, '__unicode__'):
+                # 2.5-
+                if not hasattr(ev, 'message'):
+                    # 2.4
+                    msg = len(ev.args) and ev.args[0] or ''
+                else:
+                    msg = ev.message
+                msg = force_unicode(msg, encoding=encoding)
+                clsname = force_unicode(ev.__class__.__name__,
+                        encoding=encoding)
+                ev = u'%s: %s' % (clsname, msg)
+        elif not isinstance(ev, unicode):
+            ev = repr(ev)
+
+        return force_unicode(ev, encoding=encoding)
+else:
+    def exc_to_unicode(ev, encoding='utf-8'):
+        return str(ev)
+
+def format_exception(exc_info, encoding='UTF-8'):
+    ec, ev, tb = exc_info
+
+    # Our exception object may have been turned into a string, and Python 3's
+    # traceback.format_exception() doesn't take kindly to that (it expects an
+    # actual exception object).  So we work around it, by doing the work
+    # ourselves if ev is not an exception object.
+    if not is_base_exception(ev):
+        tb_data = force_unicode(
+                ''.join(traceback.format_tb(tb)),
+                encoding)
+        ev = exc_to_unicode(ev)
+        return tb_data + ev
+    else:
+        return force_unicode(
+                ''.join(traceback.format_exception(*exc_info)),
+                encoding)