fix: allow comparison with scalar values (#88)

* fix: address failing compliance tests in DateArray and TimeArray

test: add a test session with prerelease versions of dependencies

* fix min/max/median for 2D arrays

* fixes except for null contains

* actually use NaT as 'advertised'

* fix!: use `pandas.NaT` for missing values in dbdate and dbtime dtypes

This makes them consistent with other date/time dtypes, as well as internally
consistent with the advertised `dtype.na_value`.

BREAKING-CHANGE: dbdate and dbtime dtypes return NaT instead of None for missing values

Release-As: 0.4.0

* more progress towards compliance

* address errors in TestMethods

* move tests

* add prerelease deps

* fix: address failing tests with pandas 1.5.0

test: add a test session with prerelease versions of dependencies

* fix owlbot config

* 🦉 Updates from OwlBot post-processor

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

* 🦉 Updates from OwlBot post-processor

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

* document why microsecond precision is used

* use correct units

* add box_func tests

* typo

* fix: avoid TypeError when using sorted search

* add unit tests

* fix: dbdate and dbtime support set item

* add TestMethods

* fix: allow comparison with scalar values

* correct behavior for comparison with different types and shapes

* use same dtype in shape comparison tests

Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>

Author: tswast

db_dtypes/core.py

@@ -90,14 +90,14 @@ def _cmp_method(self, other, op):
         if is_scalar(other) and (pandas.isna(other) or type(other) == self.dtype.type):
             other = type(self)([other])
 
+        if type(other) != type(self):
+            return NotImplemented
+
         oshape = getattr(other, "shape", None)
         if oshape != self.shape and oshape != (1,) and self.shape != (1,):
             raise TypeError(
                 "Can't compare arrays with different shapes", self.shape, oshape
             )
-
-        if type(other) != type(self):
-            return NotImplemented
         return op(self._ndarray, other._ndarray)
 
     def _from_factorized(self, unique, original):

tests/compliance/conftest.py

@@ -12,10 +12,23 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import operator
+
 import pandas
 import pytest
 
 
+@pytest.fixture(params=[True, False])
+def as_array(request):
+    """
+    Boolean fixture to support ExtensionDtype _from_sequence method testing.
+
+    See:
+    https://github.com/pandas-dev/pandas/blob/main/pandas/tests/extension/conftest.py
+    """
+    return request.param
+
+
 @pytest.fixture(params=[True, False])
 def as_frame(request):
     """
@@ -38,6 +51,36 @@ def as_series(request):
     return request.param
 
 
+@pytest.fixture(params=[True, False])
+def box_in_series(request):
+    """
+    Whether to box the data in a Series
+
+    See:
+    https://github.com/pandas-dev/pandas/blob/main/pandas/tests/extension/conftest.py
+    """
+    return request.param
+
+
+@pytest.fixture(
+    params=[
+        operator.eq,
+        operator.ne,
+        operator.gt,
+        operator.ge,
+        operator.lt,
+        operator.le,
+    ]
+)
+def comparison_op(request):
+    """
+    Fixture for operator module comparison functions.
+
+    See: https://github.com/pandas-dev/pandas/blob/main/pandas/conftest.py
+    """
+    return request.param
+
+
 @pytest.fixture(params=["ffill", "bfill"])
 def fillna_method(request):
     """
@@ -50,6 +93,25 @@ def fillna_method(request):
     return request.param
 
 
+@pytest.fixture(
+    params=[
+        lambda x: 1,
+        lambda x: [1] * len(x),
+        lambda x: pandas.Series([1] * len(x)),
+        lambda x: x,
+    ],
+    ids=["scalar", "list", "series", "object"],
+)
+def groupby_apply_op(request):
+    """
+    Functions to test groupby.apply().
+
+    See:
+    https://github.com/pandas-dev/pandas/blob/main/pandas/tests/extension/conftest.py
+    """
+    return request.param
+
+
 @pytest.fixture
 def invalid_scalar(data):
     """

tests/compliance/date/test_date_compliance.py

@@ -74,3 +74,27 @@ def test_value_counts(self, all_data, dropna):
         expected = pandas.Series(other).value_counts(dropna=dropna).sort_index()
 
         self.assert_series_equal(result, expected)
+
+
+class TestCasting(base.BaseCastingTests):
+    pass
+
+
+class TestGroupby(base.BaseGroupbyTests):
+    pass
+
+
+class TestSetitem(base.BaseSetitemTests):
+    pass
+
+
+class TestPrinting(base.BasePrintingTests):
+    pass
+
+
+# TODO(https://github.com/googleapis/python-db-dtypes-pandas/issues/78): Add
+# compliance tests for arithmetic operations.
+
+
+class TestComparisonOps(base.BaseComparisonOpsTests):
+    pass

tests/unit/test_dtypes.py

@@ -169,16 +169,12 @@ def test_timearray_comparisons(
         np.testing.assert_array_equal(comparisons[op](left, r), expected)
         np.testing.assert_array_equal(complements[op](left, r), ~expected)
 
-    # Bad shape
-    for bad_shape in ([], [1, 2, 3]):
+    # Bad shape, but same type
+    for bad_shape in ([], sample_values[:3]):
         with pytest.raises(
             TypeError, match="Can't compare arrays with different shapes"
         ):
-            comparisons[op](left, np.array(bad_shape))
-        with pytest.raises(
-            TypeError, match="Can't compare arrays with different shapes"
-        ):
-            complements[op](left, np.array(bad_shape))
+            comparisons[op](left, _cls(dtype)._from_sequence(bad_shape))
 
     # Bad items
     for bad_items in (