remove unused skip decorators

IPython/testing/decorators.py

@@ -152,9 +152,6 b" skip_if_not_win32 = skipif(sys.platform != 'win32',"
                            "This test only runs under Windows")
 skip_if_not_linux = skipif(not sys.platform.startswith('linux'),
                            "This test only runs under Linux")
-skip_if_not_osx = skipif(sys.platform != 'darwin',
-                         "This test only runs under OSX")
-
 
 _x11_skip_cond = (sys.platform not in ('darwin', 'win32') and
                   os.environ.get('DISPLAY', '') == '')
@@ -171,8 +168,6 b" skipif_not_numpy = skip_without('numpy')"
 
 skipif_not_matplotlib = skip_without('matplotlib')
 
-skipif_not_sympy = skip_without('sympy')
-
 # A null 'decorator', useful to make more readable code that needs to pick
 # between different decorators based on OS or other conditions
 null_deco = lambda f: f

IPython/utils/timing.py

@@ -61,8 +61,6 b' if resource is not None and hasattr(resource, "getrusage"):'
 
         Similar to clock(), but return a tuple of user/system times."""
         return resource.getrusage(resource.RUSAGE_SELF)[:2]
-
-
 else:
     # There is no distinction of user/system time under windows, so we just use
     # time.perff_counter() for everything...