add tests for period/datetime resample sum with min_count

Author: ganevgv

pandas/tests/resample/test_datetime_index.py

@@ -694,6 +694,20 @@ def test_resample_timestamp_to_period(simple_date_range_series):
     tm.assert_series_equal(result, expected)
 
 
+def test_datetime_resample_sum_min_count():
+    # GH 19974
+    index = date_range(start="2018", freq="M", periods=6)
+    data = np.ones(6)
+    data[3:6] = np.nan
+    datetime = Series(data, index)
+    result = datetime.resample("Q").sum(min_count=1)
+
+    index = date_range("2018-03-31", "2018-06-30", freq="Q-DEC")
+    expected = Series([3, np.nan], index)
+
+    tm.assert_series_equal(result, expected)
+
+
 def test_ohlc_5min():
     def _ohlc(group):
         if isna(group).all():

pandas/tests/resample/test_period_index.py

@@ -548,6 +548,19 @@ def test_quarterly_resampling(self):
         exp = ts.to_timestamp().resample("A").mean().to_period()
         tm.assert_series_equal(result, exp)
 
+    def test_period_resample_sum_min_count(self):
+        # GH 19974
+        index = date_range(start="2018", freq="M", periods=6)
+        data = np.ones(6)
+        data[3:6] = np.nan
+        period = Series(data, index).to_period()
+        result = period.resample("Q").sum(min_count=1)
+
+        index = PeriodIndex(["2018Q1", "2018Q2"], freq="Q-DEC")
+        expected = Series([3, np.nan], index)
+
+        tm.assert_series_equal(result, expected)
+
     def test_resample_weekly_bug_1726(self):
         # 8/6/12 is a Monday
         ind = date_range(start="8/6/2012", end="8/26/2012", freq="D")