update tests

Author: jbrockmendel

pandas/tests/frame/methods/test_combine_first.py

@@ -195,14 +195,15 @@ def test_combine_first_convert_datatime_correctly(
 
     def test_combine_first_align_nan(self):
         # GH 7509 (not fixed)
-        dfa = DataFrame([[pd.Timestamp("2011-01-01"), 2]], columns=["a", "b"])
+        ts = pd.Timestamp("2011-01-01").as_unit("s")
+        dfa = DataFrame([[ts, 2]], columns=["a", "b"])
         dfb = DataFrame([[4], [5]], columns=["b"])
         assert dfa["a"].dtype == "datetime64[s]"
         assert dfa["b"].dtype == "int64"
 
         res = dfa.combine_first(dfb)
         exp = DataFrame(
-            {"a": [pd.Timestamp("2011-01-01"), pd.NaT], "b": [2, 5]},
+            {"a": [ts, pd.NaT], "b": [2, 5]},
             columns=["a", "b"],
         )
         tm.assert_frame_equal(res, exp)

pandas/tests/io/json/test_pandas.py

@@ -128,7 +128,10 @@ def test_frame_non_unique_index_raises(self, orient):
             [["a", "b"], ["c", "d"]],
             [[1.5, 2.5], [3.5, 4.5]],
             [[1, 2.5], [3, 4.5]],
-            [[Timestamp("20130101"), 3.5], [Timestamp("20130102"), 4.5]],
+            [
+                [Timestamp("20130101").as_unit("s"), 3.5],
+                [Timestamp("20130102").as_unit("s"), 4.5],
+            ],
         ],
     )
     def test_frame_non_unique_columns(self, orient, data, request):

pandas/tests/io/parser/common/test_common_basic.py

@@ -69,6 +69,8 @@ def test_read_csv_local(all_parsers, csv1):
             name="index",
         ),
     )
+    if parser.engine == "pyarrow":
+        expected.index = expected.index.astype("M8[s]")
     tm.assert_frame_equal(result, expected)
 
 
@@ -188,6 +190,8 @@ def test_read_csv_dataframe(all_parsers, csv1):
             name="index",
         ),
     )
+    if parser.engine == "pyarrow":
+        expected.index = expected.index.astype("M8[s]")
     tm.assert_frame_equal(result, expected)
 
 

pandas/tests/series/methods/test_combine_first.py

@@ -80,7 +80,9 @@ def test_combine_first_dt64(self, unit):
         rs = s0.combine_first(s1)
 
         xp = Series([datetime(2010, 1, 1), "2011"], dtype=f"datetime64[{unit}]")
-
+        if unit in ["s", "ms"]:
+            # TODO: should _cast_pointwise_result attempt to preserve unit?
+            xp = xp.dt.as_unit("us")
         tm.assert_series_equal(rs, xp)
 
     def test_combine_first_dt_tz_values(self, tz_naive_fixture):