TST: Fix some interval tests

Author: pilkibun

pandas/tests/indexes/interval/test_interval.py

@@ -73,7 +73,7 @@ def test_properties(self, closed):
         tm.assert_numpy_array_equal(np.asarray(index), expected)
 
     @pytest.mark.parametrize('breaks', [
-        [1, 1, 2, 5, 15, 53, 217, 1014, 5335, 31240, 201608],
+        [1, 2, 5, 15, 53, 217, 1014, 5335, 31240, 201608],
         [-np.inf, -100, -10, 0.5, 1, 1.5, 3.8, 101, 202, np.inf],
         pd.to_datetime(['20170101', '20170202', '20170303', '20170404']),
         pd.to_timedelta(['1ns', '2ms', '3s', '4M', '5H', '6D'])])
@@ -90,6 +90,22 @@ def test_length(self, closed, breaks):
         expected = Index(iv.length if notna(iv) else iv for iv in index)
         tm.assert_index_equal(result, expected)
 
+    @pytest.mark.parametrize('breaks', [
+        [1, 1, 2, 2]])
+    @pytest.mark.parametrize('closed', ['neither', 'both'])
+    def test_length_with_point_intervals(self, closed, breaks):
+        # GH 18789
+        index = IntervalIndex.from_breaks(breaks, closed=closed)
+        result = index.length
+        expected = Index(iv.length for iv in index)
+        tm.assert_index_equal(result, expected)
+
+        # with NA
+        index = index.insert(1, np.nan)
+        result = index.length
+        expected = Index(iv.length if notna(iv) else iv for iv in index)
+        tm.assert_index_equal(result, expected)
+
     def test_with_nans(self, closed):
         index = self.create_index(closed=closed)
         assert index.hasnans is False