Parametrize value_counts test

Author: tomspur

pandas/tests/test_algos.py

@@ -962,51 +962,41 @@ def test_value_counts_uint64(self):
         if not compat.is_platform_32bit():
             tm.assert_series_equal(result, expected)
 
-    def test_value_counts_nonsorted_single_occurance(self):
+    @pytest.mark.parametrize("sort",
+                             [pytest.param(True, marks=pytest.mark.xfail), False])
+    @pytest.mark.parametrize("ascending", [True, False])
+    def test_value_counts_single_occurance(self, sort, ascending):
         # GH 12679
         # All items occour exactly once.
         # No matter if sorted or not, the resulting values should be in
         # the same order.
-        s = Series(list('bacdef'))
+        expected = Series(list('bacdef'))
 
         # Guarantee the same index if value_counts(sort=False) is used
-        vc = s.value_counts(sort=False, ascending=False)
-        tm.assert_series_equal(Series(vc.index), s)
-        vc = s.value_counts(sort=False, ascending=True)
-        tm.assert_series_equal(Series(vc.index), s)
+        vc = expected.value_counts(sort=sort, ascending=ascending)
+        result = Series(vc.index)
+        tm.assert_series_equal(result, expected)
 
-    @pytest.mark.xfail(reason="sort=True does not guarantee the same order")
-    def test_value_counts_sorted_single_occurance(self):
-        # GH 12679
-        s = Series(list('bacdef'))
-        # Guarantee does not hold yet for the sort=True case
-        vc = s.value_counts(sort=True, ascending=False)
-        tm.assert_series_equal(Series(vc.index), s)
-        vc = s.value_counts(sort=True, ascending=True)
-        tm.assert_series_equal(Series(vc.index), s)
-
-    def test_value_counts_nonsorted_double_occurance(self):
+    @pytest.mark.parametrize("ascending", [True, False])
+    def test_value_counts_nonsorted_double_occurance(self, ascending):
         # GH 12679
         # 'a' is there twice. Sorted, it should be there at the top.
         s = Series(list('bacaef'))
-        ref_nonsorted = Series(list('bacef'))
+        expected = Series(list('bacef'))
 
-        # Guarantee the same index if value_counts(sort=False) is used
-        vc = s.value_counts(sort=False, ascending=False)
-        tm.assert_series_equal(Series(vc.index), ref_nonsorted)
-        vc = s.value_counts(sort=False, ascending=True)
-        tm.assert_series_equal(Series(vc.index), ref_nonsorted)
+        vc = s.value_counts(sort=False, ascending=ascending)
+        result = Series(vc.index)
+        tm.assert_series_equal(result, expected)
 
+    @pytest.mark.parametrize("ascending, expected",
+                             [(True, Series(list('abcef'))),
+                              (False, Series(list('bcefa')))])
     @pytest.mark.xfail(reason="sort=True does not guarantee the same order")
-    def test_value_counts_sorted_double_occurance(self):
+    def test_value_counts_sorted_double_occurance(self, ascending, expected):
         # GH 12679
         s = Series(list('bacaef'))
-        ref_sorted = Series(list('abcef'))
-        # Guarantee does not hold yet for the sort=True case
-        vc = s.value_counts(sort=True, ascending=False)
-        tm.assert_series_equal(Series(vc.index), ref_sorted)
-        vc = s.value_counts(sort=True, ascending=True)
-        tm.assert_series_equal(Series(vc.index), ref_sorted)
+        vc = s.value_counts(sort=True, ascending=ascending)
+        tm.assert_series_equal(Series(vc.index), expected)
 
 
 class TestDuplicated(object):