TST: Add tests for fixed issues (#30444)

Author: mroeschke

pandas/tests/indexing/multiindex/test_loc.py

@@ -411,3 +411,29 @@ def test_loc_setitem_single_column_slice():
     df.loc[:, "B"] = np.arange(4)
     expected.iloc[:, 2] = np.arange(4)
     tm.assert_frame_equal(df, expected)
+
+
+def test_loc_nan_multiindex():
+    # GH 5286
+    tups = [
+        ("Good Things", "C", np.nan),
+        ("Good Things", "R", np.nan),
+        ("Bad Things", "C", np.nan),
+        ("Bad Things", "T", np.nan),
+        ("Okay Things", "N", "B"),
+        ("Okay Things", "N", "D"),
+        ("Okay Things", "B", np.nan),
+        ("Okay Things", "D", np.nan),
+    ]
+    df = DataFrame(
+        np.ones((8, 4)),
+        columns=Index(["d1", "d2", "d3", "d4"]),
+        index=MultiIndex.from_tuples(tups, names=["u1", "u2", "u3"]),
+    )
+    result = df.loc["Good Things"].loc["C"]
+    expected = DataFrame(
+        np.ones((1, 4)),
+        index=Index([np.nan], dtype="object", name="u3"),
+        columns=Index(["d1", "d2", "d3", "d4"], dtype="object"),
+    )
+    tm.assert_frame_equal(result, expected)

pandas/tests/resample/test_datetime_index.py

@@ -1564,3 +1564,20 @@ def test_get_timestamp_range_edges(first, last, offset, exp_first, exp_last):
     result = _get_timestamp_range_edges(first, last, offset)
     expected = (exp_first, exp_last)
     assert result == expected
+
+
+def test_resample_apply_product():
+    # GH 5586
+    index = date_range(start="2012-01-31", freq="M", periods=12)
+
+    ts = Series(range(12), index=index)
+    df = DataFrame(dict(A=ts, B=ts + 2))
+    result = df.resample("Q").apply(np.product)
+    expected = DataFrame(
+        np.array([[0, 24], [60, 210], [336, 720], [990, 1716]], dtype=np.int64),
+        index=DatetimeIndex(
+            ["2012-03-31", "2012-06-30", "2012-09-30", "2012-12-31"], freq="Q-DEC"
+        ),
+        columns=["A", "B"],
+    )
+    tm.assert_frame_equal(result, expected)

pandas/tests/reshape/merge/test_join.py

@@ -764,6 +764,35 @@ def test_join_on_tz_aware_datetimeindex(self):
         expected["vals_2"] = pd.Series([np.nan] * 2 + list("tuv"), dtype=object)
         tm.assert_frame_equal(result, expected)
 
+    def test_join_datetime_string(self):
+        # GH 5647
+        dfa = DataFrame(
+            [
+                ["2012-08-02", "L", 10],
+                ["2012-08-02", "J", 15],
+                ["2013-04-06", "L", 20],
+                ["2013-04-06", "J", 25],
+            ],
+            columns=["x", "y", "a"],
+        )
+        dfa["x"] = pd.to_datetime(dfa["x"])
+        dfb = DataFrame(
+            [["2012-08-02", "J", 1], ["2013-04-06", "L", 2]],
+            columns=["x", "y", "z"],
+            index=[2, 4],
+        )
+        dfb["x"] = pd.to_datetime(dfb["x"])
+        result = dfb.join(dfa.set_index(["x", "y"]), on=["x", "y"])
+        expected = DataFrame(
+            [
+                [pd.Timestamp("2012-08-02 00:00:00"), "J", 1, 15],
+                [pd.Timestamp("2013-04-06 00:00:00"), "L", 2, 20],
+            ],
+            index=[2, 4],
+            columns=["x", "y", "z", "a"],
+        )
+        tm.assert_frame_equal(result, expected)
+
 
 def _check_join(left, right, result, join_col, how="left", lsuffix="_x", rsuffix="_y"):