feat: accept DatasetListItem where DatasetReference is accepted (#597)

* split out and pytestify list_tables tests.

Also, exercise dataset polymorphism in some of the tests.

* list_tables now accepts DatasetListItem objects

* Get coverage to 100%

But why do we run coverage on test code?

* lint

* Update exception text for DatasetListItem

* Bypass opentelemetry tracing in unit tests.

* Got rid of opentelemetry tracing checks. They aren't needed.

* abstracted dataset-argument handling

And applied it to `list_tables` and `list_models`.

* Converted list_model tests to pytest and included check for dataset polymorphism

* removed unneeded blanl lines.

* Made list_routines accept DatasetListItem

and conveted list_routines tests to pytest.

* create_dataset accepts DatasetListItem

Also converted create_dataset tests to pytest.

(And fixed some long lines.)

* Converted list_routine tests to pytest

* include string dataset representation in dataset polymorphism.

* removed some unused imports

* Updated delete_dataset tests

- Polymorphoc on dataset
- pytest

* black

* lint

* We don't actually need to avoid opentelemetry

And a 3.6 test dependened on it.

* fixed docstrings to include DatasetListItem in dataset polymorphic APIs.

google/cloud/bigquery/client.py

@@ -449,6 +449,22 @@ def _create_bqstorage_client(self):
 
         return bigquery_storage.BigQueryReadClient(credentials=self._credentials)
 
+    def _dataset_from_arg(self, dataset):
+        if isinstance(dataset, str):
+            dataset = DatasetReference.from_string(
+                dataset, default_project=self.project
+            )
+
+        if not isinstance(dataset, (Dataset, DatasetReference)):
+            if isinstance(dataset, DatasetListItem):
+                dataset = dataset.reference
+            else:
+                raise TypeError(
+                    "dataset must be a Dataset, DatasetReference, DatasetListItem,"
+                    " or string"
+                )
+        return dataset
+
     def create_dataset(
         self, dataset, exists_ok=False, retry=DEFAULT_RETRY, timeout=None
     ):
@@ -461,6 +477,7 @@ def create_dataset(
             dataset (Union[ \
                 google.cloud.bigquery.dataset.Dataset, \
                 google.cloud.bigquery.dataset.DatasetReference, \
+                google.cloud.bigquery.dataset.DatasetListItem, \
                 str, \
             ]):
                 A :class:`~google.cloud.bigquery.dataset.Dataset` to create.
@@ -491,10 +508,7 @@ def create_dataset(
             >>> dataset = client.create_dataset(dataset)
 
         """
-        if isinstance(dataset, str):
-            dataset = DatasetReference.from_string(
-                dataset, default_project=self.project
-            )
+        dataset = self._dataset_from_arg(dataset)
         if isinstance(dataset, DatasetReference):
             dataset = Dataset(dataset)
 
@@ -1133,6 +1147,7 @@ def list_models(
             dataset (Union[ \
                 google.cloud.bigquery.dataset.Dataset, \
                 google.cloud.bigquery.dataset.DatasetReference, \
+                google.cloud.bigquery.dataset.DatasetListItem, \
                 str, \
             ]):
                 A reference to the dataset whose models to list from the
@@ -1160,13 +1175,7 @@ def list_models(
                 :class:`~google.cloud.bigquery.model.Model` contained
                 within the requested dataset.
         """
-        if isinstance(dataset, str):
-            dataset = DatasetReference.from_string(
-                dataset, default_project=self.project
-            )
-
-        if not isinstance(dataset, (Dataset, DatasetReference)):
-            raise TypeError("dataset must be a Dataset, DatasetReference, or string")
+        dataset = self._dataset_from_arg(dataset)
 
         path = "%s/models" % dataset.path
         span_attributes = {"path": path}
@@ -1210,6 +1219,7 @@ def list_routines(
             dataset (Union[ \
                 google.cloud.bigquery.dataset.Dataset, \
                 google.cloud.bigquery.dataset.DatasetReference, \
+                google.cloud.bigquery.dataset.DatasetListItem, \
                 str, \
             ]):
                 A reference to the dataset whose routines to list from the
@@ -1237,14 +1247,7 @@ def list_routines(
                 :class:`~google.cloud.bigquery.routine.Routine`s contained
                 within the requested dataset, limited by ``max_results``.
         """
-        if isinstance(dataset, str):
-            dataset = DatasetReference.from_string(
-                dataset, default_project=self.project
-            )
-
-        if not isinstance(dataset, (Dataset, DatasetReference)):
-            raise TypeError("dataset must be a Dataset, DatasetReference, or string")
-
+        dataset = self._dataset_from_arg(dataset)
         path = "{}/routines".format(dataset.path)
 
         span_attributes = {"path": path}
@@ -1288,6 +1291,7 @@ def list_tables(
             dataset (Union[ \
                 google.cloud.bigquery.dataset.Dataset, \
                 google.cloud.bigquery.dataset.DatasetReference, \
+                google.cloud.bigquery.dataset.DatasetListItem, \
                 str, \
             ]):
                 A reference to the dataset whose tables to list from the
@@ -1315,14 +1319,7 @@ def list_tables(
                 :class:`~google.cloud.bigquery.table.TableListItem` contained
                 within the requested dataset.
         """
-        if isinstance(dataset, str):
-            dataset = DatasetReference.from_string(
-                dataset, default_project=self.project
-            )
-
-        if not isinstance(dataset, (Dataset, DatasetReference)):
-            raise TypeError("dataset must be a Dataset, DatasetReference, or string")
-
+        dataset = self._dataset_from_arg(dataset)
         path = "%s/tables" % dataset.path
         span_attributes = {"path": path}
 
@@ -1365,6 +1362,7 @@ def delete_dataset(
             dataset (Union[ \
                 google.cloud.bigquery.dataset.Dataset, \
                 google.cloud.bigquery.dataset.DatasetReference, \
+                google.cloud.bigquery.dataset.DatasetListItem, \
                 str, \
             ]):
                 A reference to the dataset to delete. If a string is passed
@@ -1384,14 +1382,7 @@ def delete_dataset(
                 Defaults to ``False``. If ``True``, ignore "not found" errors
                 when deleting the dataset.
         """
-        if isinstance(dataset, str):
-            dataset = DatasetReference.from_string(
-                dataset, default_project=self.project
-            )
-
-        if not isinstance(dataset, (Dataset, DatasetReference)):
-            raise TypeError("dataset must be a Dataset or a DatasetReference")
-
+        dataset = self._dataset_from_arg(dataset)
         params = {}
         path = dataset.path
         if delete_contents:

tests/unit/conftest.py

@@ -0,0 +1,23 @@
+import pytest
+
+from .helpers import make_client
+
+
+@pytest.fixture
+def client():
+    yield make_client()
+
+
+@pytest.fixture
+def PROJECT():
+    yield "PROJECT"
+
+
+@pytest.fixture
+def DS_ID():
+    yield "DATASET_ID"
+
+
+@pytest.fixture
+def LOCATION():
+    yield "us-central"

tests/unit/helpers.py

@@ -12,6 +12,11 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import google.cloud.bigquery.client
+import google.cloud.bigquery.dataset
+import mock
+import pytest
+
 
 def make_connection(*responses):
     import google.cloud.bigquery._http
@@ -31,3 +36,47 @@ def _to_pyarrow(value):
     import pyarrow
 
     return pyarrow.array([value])[0]
+
+
+def make_client(project="PROJECT", **kw):
+    credentials = mock.Mock(spec=google.auth.credentials.Credentials)
+    return google.cloud.bigquery.client.Client(project, credentials, **kw)
+
+
+def make_dataset_reference_string(project, ds_id):
+    return f"{project}.{ds_id}"
+
+
+def make_dataset(project, ds_id):
+    return google.cloud.bigquery.dataset.Dataset(
+        google.cloud.bigquery.dataset.DatasetReference(project, ds_id)
+    )
+
+
+def make_dataset_list_item(project, ds_id):
+    return google.cloud.bigquery.dataset.DatasetListItem(
+        dict(datasetReference=dict(projectId=project, datasetId=ds_id))
+    )
+
+
+def identity(x):
+    return x
+
+
+def get_reference(x):
+    return x.reference
+
+
+dataset_like = [
+    (google.cloud.bigquery.dataset.DatasetReference, identity),
+    (make_dataset, identity),
+    (make_dataset_list_item, get_reference),
+    (
+        make_dataset_reference_string,
+        google.cloud.bigquery.dataset.DatasetReference.from_string,
+    ),
+]
+
+dataset_polymorphic = pytest.mark.parametrize(
+    "make_dataset,get_reference", dataset_like
+)