feat: add response status to DirectRow.commit() (#128)

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Fixes #127  🦕

google/cloud/bigtable/row.py

@@ -457,12 +457,18 @@ def commit(self):
             :end-before: [END bigtable_row_commit]
             :dedent: 4
 
+        :rtype: :class:`~google.rpc.status_pb2.Status`
+        :returns: A response status (`google.rpc.status_pb2.Status`)
+                  representing success or failure of the row committed.
         :raises: :exc:`~.table.TooManyMutationsError` if the number of
                  mutations is greater than 100,000.
         """
-        self._table.mutate_rows([self])
+        response = self._table.mutate_rows([self])
+
         self.clear()
 
+        return response[0]
+
     def clear(self):
         """Removes all currently accumulated mutations on the current row.
 

tests/unit/test_row.py

@@ -359,6 +359,29 @@ def test_commit(self):
         row.commit()
         self.assertEqual(table.mutated_rows, [row])
 
+    def test_commit_with_exception(self):
+        from google.rpc import status_pb2
+
+        project_id = "project-id"
+        row_key = b"row_key"
+        table_name = "projects/more-stuff"
+        column_family_id = u"column_family_id"
+        column = b"column"
+
+        credentials = _make_credentials()
+        client = self._make_client(
+            project=project_id, credentials=credentials, admin=True
+        )
+        table = _Table(table_name, client=client)
+        row = self._make_one(row_key, table)
+        value = b"bytes-value"
+
+        # Perform the method and check the result.
+        row.set_cell(column_family_id, column, value)
+        result = row.commit()
+        expected = status_pb2.Status(code=0)
+        self.assertEqual(result, expected)
+
 
 class TestConditionalRow(unittest.TestCase):
     @staticmethod
@@ -832,4 +855,7 @@ def __init__(self, name, client=None, app_profile_id=None):
         self.mutated_rows = []
 
     def mutate_rows(self, rows):
+        from google.rpc import status_pb2
+
         self.mutated_rows.extend(rows)
+        return [status_pb2.Status(code=0)]