diff --git a/pandas/tests/frame/indexing/test_where.py b/pandas/tests/frame/indexing/test_where.py
index 7244624e563e3..32a499f6e9168 100644
--- a/pandas/tests/frame/indexing/test_where.py
+++ b/pandas/tests/frame/indexing/test_where.py
@@ -745,3 +745,15 @@ def test_where_bool_comparison():
}
)
tm.assert_frame_equal(result, expected)
+
+
+def test_where_none_nan_coerce():
+ # GH 15613
+ expected = DataFrame(
+ {
+ "A": [Timestamp("20130101"), pd.NaT, Timestamp("20130103")],
+ "B": [1, 2, np.nan],
+ }
+ )
+ result = expected.where(expected.notnull(), None)
+ tm.assert_frame_equal(result, expected)
diff --git a/pandas/tests/frame/methods/test_to_csv.py b/pandas/tests/frame/methods/test_to_csv.py
index 3b2668aea001c..769b08373b890 100644
--- a/pandas/tests/frame/methods/test_to_csv.py
+++ b/pandas/tests/frame/methods/test_to_csv.py
@@ -1330,3 +1330,14 @@ def test_to_csv_numpy_16_bug(self):
result = buf.getvalue()
assert "2000-01-01" in result
+
+ def test_to_csv_na_quoting(self):
+ # GH 15891
+ # Normalize carriage return for Windows OS
+ result = (
+ DataFrame([None, None])
+ .to_csv(None, header=False, index=False, na_rep="")
+ .replace("\r\n", "\n")
+ )
+ expected = '""\n""\n'
+ assert result == expected
diff --git a/pandas/tests/groupby/test_groupby.py b/pandas/tests/groupby/test_groupby.py
index c37dc17b85dd2..31acbb02518fb 100644
--- a/pandas/tests/groupby/test_groupby.py
+++ b/pandas/tests/groupby/test_groupby.py
@@ -1657,7 +1657,7 @@ def test_index_label_overlaps_location():
expected = ser.take([1, 3, 4])
tm.assert_series_equal(actual, expected)
- # ... and again, with a generic Index of floats
+ # and again, with a generic Index of floats
df.index = df.index.astype(float)
g = df.groupby(list("ababb"))
actual = g.filter(lambda x: len(x) > 2)
@@ -2283,3 +2283,23 @@ def test_groupby_empty_multi_column():
[], columns=["C"], index=MultiIndex([[], []], [[], []], names=["A", "B"])
)
tm.assert_frame_equal(result, expected)
+
+
+def test_groupby_filtered_df_std():
+ # GH 16174
+ dicts = [
+ {"filter_col": False, "groupby_col": True, "bool_col": True, "float_col": 10.5},
+ {"filter_col": True, "groupby_col": True, "bool_col": True, "float_col": 20.5},
+ {"filter_col": True, "groupby_col": True, "bool_col": True, "float_col": 30.5},
+ ]
+ df = DataFrame(dicts)
+
+ df_filter = df[df["filter_col"] == True] # noqa:E712
+ dfgb = df_filter.groupby("groupby_col")
+ result = dfgb.std()
+ expected = DataFrame(
+ [[0.0, 0.0, 7.071068]],
+ columns=["filter_col", "bool_col", "float_col"],
+ index=Index([True], name="groupby_col"),
+ )
+ tm.assert_frame_equal(result, expected)
diff --git a/pandas/tests/indexing/multiindex/test_loc.py b/pandas/tests/indexing/multiindex/test_loc.py
index 0c6f2faf77f00..558270ac86532 100644
--- a/pandas/tests/indexing/multiindex/test_loc.py
+++ b/pandas/tests/indexing/multiindex/test_loc.py
@@ -801,3 +801,33 @@ def test_mi_partial_indexing_list_raises():
frame.columns.names = ["state", "color"]
with pytest.raises(KeyError, match="\\[2\\] not in index"):
frame.loc[["b", 2], "Colorado"]
+
+
+def test_mi_indexing_list_nonexistent_raises():
+ # GH 15452
+ s = Series(range(4), index=MultiIndex.from_product([[1, 2], ["a", "b"]]))
+ with pytest.raises(KeyError, match="\\['not' 'found'\\] not in index"):
+ s.loc[["not", "found"]]
+
+
+def test_mi_add_cell_missing_row_non_unique():
+ # GH 16018
+ result = DataFrame(
+ [[1, 2, 5, 6], [3, 4, 7, 8]],
+ index=["a", "a"],
+ columns=MultiIndex.from_product([[1, 2], ["A", "B"]]),
+ )
+ result.loc["c"] = -1
+ result.loc["c", (1, "A")] = 3
+ result.loc["d", (1, "A")] = 3
+ expected = DataFrame(
+ [
+ [1.0, 2.0, 5.0, 6.0],
+ [3.0, 4.0, 7.0, 8.0],
+ [3.0, -1.0, -1, -1],
+ [3.0, np.nan, np.nan, np.nan],
+ ],
+ index=["a", "a", "c", "d"],
+ columns=MultiIndex.from_product([[1, 2], ["A", "B"]]),
+ )
+ tm.assert_frame_equal(result, expected)
diff --git a/pandas/tests/indexing/test_loc.py b/pandas/tests/indexing/test_loc.py
index 48bc3e18d9883..b8e7b83c97ddb 100644
--- a/pandas/tests/indexing/test_loc.py
+++ b/pandas/tests/indexing/test_loc.py
@@ -2684,3 +2684,14 @@ def test_loc_assign_dict_to_row(self, dtype):
expected = DataFrame({"A": ["newA", "def"], "B": ["newB", "jkl"]}, dtype=dtype)
tm.assert_frame_equal(df, expected)
+
+ @td.skip_array_manager_invalid_test
+ def test_loc_setitem_dict_timedelta_multiple_set(self):
+ # GH 16309
+ result = DataFrame(columns=["time", "value"])
+ result.loc[1] = {"time": Timedelta(6, unit="s"), "value": "foo"}
+ result.loc[1] = {"time": Timedelta(6, unit="s"), "value": "foo"}
+ expected = DataFrame(
+ [[Timedelta(6, unit="s"), "foo"]], columns=["time", "value"], index=[1]
+ )
+ tm.assert_frame_equal(result, expected)
diff --git a/pandas/tests/scalar/timestamp/test_constructors.py b/pandas/tests/scalar/timestamp/test_constructors.py
index 2340d154e9e10..83e40aa5cb96b 100644
--- a/pandas/tests/scalar/timestamp/test_constructors.py
+++ b/pandas/tests/scalar/timestamp/test_constructors.py
@@ -437,6 +437,13 @@ def test_bounds_with_different_units(self):
dt64 = np.datetime64(date_string, unit)
Timestamp(dt64)
+ @pytest.mark.parametrize("arg", ["001-01-01", "0001-01-01"])
+ def test_out_of_bounds_string_consistency(self, arg):
+ # GH 15829
+ msg = "Out of bounds"
+ with pytest.raises(OutOfBoundsDatetime, match=msg):
+ Timestamp(arg)
+
def test_min_valid(self):
# Ensure that Timestamp.min is a valid Timestamp
Timestamp(Timestamp.min)
diff --git a/pandas/tests/tools/test_to_numeric.py b/pandas/tests/tools/test_to_numeric.py
index e863fb45b1f81..eecb9492f29e3 100644
--- a/pandas/tests/tools/test_to_numeric.py
+++ b/pandas/tests/tools/test_to_numeric.py
@@ -780,3 +780,10 @@ def test_downcast_nullable_mask_is_copied():
arr[1] = pd.NA # should not modify result
tm.assert_extension_array_equal(result, expected)
+
+
+def test_to_numeric_scientific_notation():
+ # GH 15898
+ result = to_numeric("1.7e+308")
+ expected = np.float64(1.7e308)
+ assert result == expected