cleans up type hints and some minor tweaks

google/cloud/bigquery/schema.py

@@ -17,13 +17,11 @@
 from __future__ import annotations
 import collections
 import enum
+import typing
 from typing import Any, cast, Dict, Iterable, Optional, Union
 
 from google.cloud.bigquery import _helpers
 from google.cloud.bigquery import standard_sql
-from google.cloud.bigquery._helpers import (
-    _isinstance_or_raise,
-)
 from google.cloud.bigquery.enums import StandardSqlTypeNames
 
 
@@ -564,8 +562,9 @@ def to_api_repr(self) -> dict:
 
 class SerDeInfo:
     """Serializer and deserializer information.
+
     Args:
-        serializationLibrary (str): Required. Specifies a fully-qualified class
+        serialization_library (str): Required. Specifies a fully-qualified class
             name of the serialization library that is responsible for the
             translation of data between table representation and the underlying
             low-level input and output format structures. The maximum length is
@@ -588,40 +587,40 @@ def __init__(
         self.parameters = parameters
 
     @property
-    def serialization_library(self) -> Any:
+    def serialization_library(self) -> str:
         """Required. Specifies a fully-qualified class name of the serialization
         library that is responsible for the translation of data between table
         representation and the underlying low-level input and output format
         structures. The maximum length is 256 characters."""
 
-        return self._properties.get("serializationLibrary")
+        return typing.cast(str, self._properties.get("serializationLibrary"))
 
     @serialization_library.setter
     def serialization_library(self, value: str):
-        value = _isinstance_or_raise(value, str, none_allowed=False)
+        value = _helpers._isinstance_or_raise(value, str, none_allowed=False)
         self._properties["serializationLibrary"] = value
 
     @property
-    def name(self) -> Any:
+    def name(self) -> Optional[str]:
         """Optional. Name of the SerDe. The maximum length is 256 characters."""
 
         return self._properties.get("name")
 
     @name.setter
     def name(self, value: Optional[str] = None):
-        value = _isinstance_or_raise(value, str, none_allowed=True)
+        value = _helpers._isinstance_or_raise(value, str, none_allowed=True)
         self._properties["name"] = value
 
     @property
-    def parameters(self) -> Any:
+    def parameters(self) -> Optional[dict[str, str]]:
         """Optional. Key-value pairs that define the initialization parameters
         for the serialization library. Maximum size 10 Kib."""
 
         return self._properties.get("parameters")
 
     @parameters.setter
     def parameters(self, value: Optional[dict[str, str]] = None):
-        value = _isinstance_or_raise(value, dict, none_allowed=True)
+        value = _helpers._isinstance_or_raise(value, dict, none_allowed=True)
         self._properties["parameters"] = value
 
     def to_api_repr(self) -> dict:

tests/unit/test_schema.py

@@ -20,10 +20,8 @@
 
 from google.cloud import bigquery
 from google.cloud.bigquery.standard_sql import StandardSqlStructType
-from google.cloud.bigquery.schema import (
-    PolicyTagList,
-    SerDeInfo,
-)
+from google.cloud.bigquery import schema
+from google.cloud.bigquery.schema import PolicyTagList
 
 
 class TestSchemaField(unittest.TestCase):
@@ -133,8 +131,6 @@ def test_constructor_range_str(self):
         self.assertEqual(field.range_element_type.element_type, "DATETIME")
 
     def test_to_api_repr(self):
-        from google.cloud.bigquery.schema import PolicyTagList
-
         policy = PolicyTagList(names=("foo", "bar"))
         self.assertEqual(
             policy.to_api_repr(),
@@ -889,8 +885,6 @@ def test_valid_mapping_representation(self):
 class TestPolicyTags(unittest.TestCase):
     @staticmethod
     def _get_target_class():
-        from google.cloud.bigquery.schema import PolicyTagList
-
         return PolicyTagList
 
     def _make_one(self, *args, **kw):
@@ -1139,7 +1133,7 @@ class TestSerDeInfo:
 
     @staticmethod
     def _get_target_class():
-        return SerDeInfo
+        return schema.SerDeInfo
 
     def _make_one(self, *args, **kwargs):
         return self._get_target_class()(*args, **kwargs)