Partly revert "remove now-obsolete use of skip_doctest outside core"

This partly reverts commit 02234da0d461f5ddee142d51952dc10a86b8074e.

test_decorators.py is intended to test skip_doctest, the removing was wrong.

IPython/testing/tests/test_decorators.py

@@ -1,164 +1,168 b''
 """Tests for the decorators we've created for IPython.
 """
 
 # Module imports
 # Std lib
 import inspect
 import sys
 
 # Third party
 import nose.tools as nt
 
 # Our own
 from IPython.testing import decorators as dec
+from IPython.testing.skipdoctest import skip_doctest
 
 #-----------------------------------------------------------------------------
 # Utilities
 
 # Note: copied from OInspect, kept here so the testing stuff doesn't create
 # circular dependencies and is easier to reuse.
 def getargspec(obj):
     """Get the names and default values of a function's arguments.
 
     A tuple of four things is returned: (args, varargs, varkw, defaults).
     'args' is a list of the argument names (it may contain nested lists).
     'varargs' and 'varkw' are the names of the * and ** arguments or None.
     'defaults' is an n-tuple of the default values of the last n arguments.
 
     Modified version of inspect.getargspec from the Python Standard
     Library."""
 
     if inspect.isfunction(obj):
         func_obj = obj
     elif inspect.ismethod(obj):
         func_obj = obj.__func__
     else:
         raise TypeError('arg is not a Python function')
     args, varargs, varkw = inspect.getargs(func_obj.__code__)
     return args, varargs, varkw, func_obj.__defaults__
 
 #-----------------------------------------------------------------------------
 # Testing functions
 
 @dec.as_unittest
 def trivial():
     """A trivial test"""
     pass
 
 
 @dec.skip()
 def test_deliberately_broken():
     """A deliberately broken test - we want to skip this one."""
     1/0
 
 @dec.skip('Testing the skip decorator')
 def test_deliberately_broken2():
     """Another deliberately broken test - we want to skip this one."""
     1/0
 
 
 # Verify that we can correctly skip the doctest for a function at will, but
 # that the docstring itself is NOT destroyed by the decorator.
+@skip_doctest
 def doctest_bad(x,y=1,**k):
     """A function whose doctest we need to skip.
 
     >>> 1+1
     3
     """
     print('x:',x)
     print('y:',y)
     print('k:',k)
 
 
 def call_doctest_bad():
     """Check that we can still call the decorated functions.
     
     >>> doctest_bad(3,y=4)
     x: 3
     y: 4
     k: {}
     """
     pass
 
 
 def test_skip_dt_decorator():
     """Doctest-skipping decorator should preserve the docstring.
     """
     # Careful: 'check' must be a *verbatim* copy of the doctest_bad docstring!
     check = """A function whose doctest we need to skip.
 
     >>> 1+1
     3
     """
     # Fetch the docstring from doctest_bad after decoration.
     val = doctest_bad.__doc__
     
     nt.assert_equal(check,val,"doctest_bad docstrings don't match")
 
 
 # Doctest skipping should work for class methods too
 class FooClass(object):
     """FooClass
 
     Example:
 
     >>> 1+1
     2
     """
 
+    @skip_doctest
     def __init__(self,x):
         """Make a FooClass.
 
         Example:
 
         >>> f = FooClass(3)
         junk
         """
         print('Making a FooClass.')
         self.x = x
         
+    @skip_doctest
     def bar(self,y):
         """Example:
 
         >>> ff = FooClass(3)
         >>> ff.bar(0)
         boom!
         >>> 1/0
         bam!
         """
         return 1/y
 
     def baz(self,y):
         """Example:
 
         >>> ff2 = FooClass(3)
         Making a FooClass.
         >>> ff2.baz(3)
         True
         """
         return self.x==y
 
 
 def test_skip_dt_decorator2():
     """Doctest-skipping decorator should preserve function signature.
     """
     # Hardcoded correct answer
     dtargs = (['x', 'y'], None, 'k', (1,))
     # Introspect out the value
     dtargsr = getargspec(doctest_bad)
     assert dtargsr==dtargs, \
            "Incorrectly reconstructed args for doctest_bad: %s" % (dtargsr,)
 
 
 @dec.skip_linux
 def test_linux():
     nt.assert_false(sys.platform.startswith('linux'),"This test can't run under linux")
 
 @dec.skip_win32
 def test_win32():
     nt.assert_not_equal(sys.platform,'win32',"This test can't run under windows")
 
 @dec.skip_osx
 def test_osx():
     nt.assert_not_equal(sys.platform,'darwin',"This test can't run under osx")