teardown registered in tests

Signed-off-by: Nathaniel Starkman (@nstarman) <nstarkman@protonmail.com>

astropy/units/quantity_helper/helpers.py

@@ -389,7 +389,7 @@ def register_ufunc(ufunc, inunits, ounits, *, assume_correct_units=False):
     if the python function works only on scalars, but we want to be able to
     pass in arrays. ``c2f`` will work on arrays, but pretending it didn't...
 
-        >>> ufunc = np.frompyfunc(c2f, 1, 1); ufunc
+        >>> ufunc = np.frompyfunc(c2f, 1, 1); ufunc  # doctest: +SKIP
         <ufunc 'c2f (vectorized)'>
 
     One of the limitations of a `numpy.ufunc` is that it cannot work with

astropy/units/tests/test_quantity_ufuncs.py

@@ -2,6 +2,7 @@
 # returns quantities with the right units, or raises exceptions.
 
 import concurrent.futures
+import copy
 import inspect
 import warnings
 from collections import namedtuple
@@ -1397,6 +1398,9 @@ def funcobj_2_2(x: "km", y: "km") -> (object, object):
 class TestRegisterUfunc:
 
     def setup_class(self):
+        # start by saving a copy of REGISTERED_NARG_UFUNCS
+        self.REGISTERED_NARG_UFUNCS = copy.deepcopy(qh.REGISTERED_NARG_UFUNCS)
+
         # registry of normal ufuncs
         self.ufunc_registry = {
             func: np.frompyfunc(func, *map(int, func.__name__.split("_")[1:]))
@@ -1422,6 +1426,10 @@ def setup_class(self):
                            ounits=[u.km] * ufunc.nout,
                            assume_correct_units=True)
 
+    def teardown_class(self):
+        # restore REGISTERED_NARG_UFUNCS
+        qh.REGISTERED_NARG_UFUNCS = self.REGISTERED_NARG_UFUNCS
+
     # -------------------
     # variety of funcs
 
@@ -1505,6 +1513,9 @@ class TestQuantityFromPyFunc:
     """Test `astropy.units.utils.frompyfunc`."""
 
     def setup_class(self):
+        # start by saving a copy of REGISTERED_NARG_UFUNCS
+        self.REGISTERED_NARG_UFUNCS = copy.deepcopy(qh.REGISTERED_NARG_UFUNCS)
+
         # registry of ufuncs
         self.ufunc_registry = {}
         self.ufunc_assume_registry = {}
@@ -1524,6 +1535,10 @@ def setup_class(self):
             self.ufunc_introspect_assume_registry[func] = frompyfunc(
                 func, nin, nout, assume_correct_units=True)
 
+    def teardown_class(self):
+        # restore REGISTERED_NARG_UFUNCS
+        qh.REGISTERED_NARG_UFUNCS = self.REGISTERED_NARG_UFUNCS
+
     # -------------------
     # variety of funcs
 

astropy/units/utils.py

@@ -368,7 +368,7 @@ def frompyfunc(func, nin, nout, inunits=None, ounits=None,
 
         >>> ufunc = frompyfunc(c2f, nin=1, nout=1,
         ...                             inunits=u.Celsius, ounits=Fahrenheit)
-        >>> ufunc
+        >>> ufunc  # doctest: +SKIP
         <ufunc 'c2f (vectorized)'>
 
         >>> ufunc(36 * u.Celsius)