stop suppressing addError on SkipTest and DeprecatedTest

ErrorClass returns True on addError to prevent SkipTest and
DeprecatedTest from getting to the pdb plugin. However this prevents
all plugins from getting them, and the documentation specifies that
these exceptions should get to the plugins. The pdb plugin should handle
these exceptions explicitly as the documentation suggests.
This also deprecates Google Code Issue nose-devs#101 so there is nothing to test
there anymore.
This fixes nose-devs#45.

nose/plugins/debug.py

@@ -6,6 +6,9 @@
 
 import pdb
 from nose.plugins.base import Plugin
+from nose.util import isclass
+from nose.plugins.skip import SkipTest
+from nose.plugins.deprecated import DeprecatedTest
 
 class Pdb(Plugin):
     """
@@ -37,16 +40,26 @@ def configure(self, options, conf):
         self.enabled_for_errors = options.debugErrors
         self.enabled_for_failures = options.debugFailures
 
+    def _filterError(self, err):
+        if isinstance(err, tuple) and isclass(err[0]):
+            if issubclass(err[0], SkipTest) or issubclass(err[0], DeprecatedTest):
+                return True
+        return False
+
     def addError(self, test, err):
         """Enter pdb if configured to debug errors.
         """
+        if self._filterError(err):
+            return
         if not self.enabled_for_errors:
             return
         self.debug(err)
 
     def addFailure(self, test, err):
         """Enter pdb if configured to debug failures.
         """
+        if self._filterError(err):
+            return
         if not self.enabled_for_failures:
             return
         self.debug(err)

nose/plugins/errorclass.py

@@ -95,7 +95,6 @@
 from nose.pyversion import make_instancemethod
 from nose.plugins.base import Plugin
 from nose.result import TextTestResult
-from nose.util import isclass
 
 class MetaErrorClass(type):
     """Metaclass for ErrorClassPlugins that allows error classes to be
@@ -136,14 +135,6 @@ class ErrorClassPlugin(Plugin):
     score = 1000
     errorClasses = ()
 
-    def addError(self, test, err):
-        err_cls, a, b = err
-        if not isclass(err_cls):
-            return
-        classes = [e[0] for e in self.errorClasses]
-        if filter(lambda c: issubclass(err_cls, c), classes):
-            return True
-
     def prepareTestResult(self, result):
         if not hasattr(result, 'errorClasses'):
             self.patchResult(result)