Unittests for GH#9836

Author: jankatins

pandas/tests/test_categorical.py

@@ -114,6 +114,9 @@ def f():
             Categorical([1,2], [1,2,np.nan, np.nan])
         self.assertRaises(ValueError, f)
 
+        # The default should be unordered
+        c1 = Categorical(["a", "b", "c", "a"])
+        self.assertFalse(c1.ordered)
 
         # Categorical as input
         c1 = Categorical(["a", "b", "c", "a"])
@@ -367,6 +370,13 @@ def f():
             self.assertRaises(TypeError, lambda: a < cat)
             self.assertRaises(TypeError, lambda: a < cat_rev)
 
+        # Make sure that unequal comparison take the categories order in account
+        cat_rev = pd.Categorical(list("abc"), categories=list("cba"), ordered=True)
+        exp = np.array([True, False, False])
+        res = cat_rev > "b"
+        self.assert_numpy_array_equal(res, exp)
+
+
     def test_na_flags_int_categories(self):
         # #1457
 
@@ -2390,6 +2400,14 @@ def test_comparisons(self):
             exp = Series([False, False, True])
             tm.assert_series_equal(res, exp)
 
+            scalar = base[1]
+            res = cat > scalar
+            exp = Series([False, False, True])
+            tm.assert_series_equal(res, exp)
+            res_rev = cat_rev > scalar
+            exp_rev = Series([True, False, False])
+            tm.assert_series_equal(res_rev, exp_rev)
+
             # Only categories with same categories can be compared
             def f():
                 cat > cat_rev
@@ -2412,6 +2430,17 @@ def f():
             res = cat_rev > base[0]
             tm.assert_series_equal(res, exp)
 
+        # unequal comparison should raise for unordered cats
+        cat = Series(Categorical(list("abc")))
+        def f():
+            cat > "b"
+        self.assertRaises(TypeError, f)
+        cat = Series(Categorical(list("abc"), ordered=False))
+        def f():
+            cat > "b"
+        self.assertRaises(TypeError, f)
+
+
         # And test NaN handling...
         cat = Series(Categorical(["a","b","c", np.nan]))
         exp = Series([True, True, True, False])