From 1cbae6a24587e1757035b852ce31a5b86e194b69 Mon Sep 17 00:00:00 2001
From: Chris Wilcox <crwilcox@google.com>
Date: Thu, 25 Jun 2020 15:41:55 -0700
Subject: [PATCH 01/25] fix: add oneof fields to genereated protoplus init

---
 .../%namespace/%name_%version/%sub/types/_message.py.j2          | 1 +
 1 file changed, 1 insertion(+)

diff --git a/gapic/templates/%namespace/%name_%version/%sub/types/_message.py.j2 b/gapic/templates/%namespace/%name_%version/%sub/types/_message.py.j2
index e9586108c0..e71ea0f70f 100644
--- a/gapic/templates/%namespace/%name_%version/%sub/types/_message.py.j2
+++ b/gapic/templates/%namespace/%name_%version/%sub/types/_message.py.j2
@@ -43,6 +43,7 @@ class {{ message.name }}({{ p }}.Message):
     {% else -%}
     {{ field.name }} = {{ p }}.{% if field.repeated %}Repeated{% endif %}Field(
         {{- p }}.{{ field.proto_type }}, number={{ field.number }}
+    {% if field.oneof %}, oneof='{{ field.oneof }}'{% endif %}
     {%- if field.enum or field.message %},
         {{ field.proto_type.lower() }}={{ field.type.ident.rel(message.ident) }},
     {% endif %})

From f104ba0eafa97f5a1d68faeaeb9f4e33ff97b7bf Mon Sep 17 00:00:00 2001
From: Chris Wilcox <crwilcox@google.com>
Date: Thu, 25 Jun 2020 16:58:35 -0700
Subject: [PATCH 02/25] Add a one of field to the Field dataclass

---
 gapic/schema/wrappers.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/gapic/schema/wrappers.py b/gapic/schema/wrappers.py
index 5a632fcc02..edce4ca763 100644
--- a/gapic/schema/wrappers.py
+++ b/gapic/schema/wrappers.py
@@ -54,6 +54,8 @@ class Field:
     meta: metadata.Metadata = dataclasses.field(
         default_factory=metadata.Metadata,
     )
+    oneof:bool = False
+
 
     def __getattr__(self, name):
         return getattr(self.field_pb, name)

From 1f8ee9cffa28c19c7fa771c07d5cbe3f6985fe04 Mon Sep 17 00:00:00 2001
From: Chris Wilcox <crwilcox@google.com>
Date: Thu, 25 Jun 2020 17:03:33 -0700
Subject: [PATCH 03/25] style

---
 gapic/schema/wrappers.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gapic/schema/wrappers.py b/gapic/schema/wrappers.py
index edce4ca763..434c5c8e63 100644
--- a/gapic/schema/wrappers.py
+++ b/gapic/schema/wrappers.py
@@ -54,7 +54,7 @@ class Field:
     meta: metadata.Metadata = dataclasses.field(
         default_factory=metadata.Metadata,
     )
-    oneof:bool = False
+    oneof: bool = False
 
 
     def __getattr__(self, name):

From 7438862c3381aa33bd2c490bfd39180933ee0a41 Mon Sep 17 00:00:00 2001
From: Chris Wilcox <crwilcox@google.com>
Date: Thu, 25 Jun 2020 17:11:39 -0700
Subject: [PATCH 04/25] style

---
 gapic/schema/wrappers.py | 1 -
 1 file changed, 1 deletion(-)

diff --git a/gapic/schema/wrappers.py b/gapic/schema/wrappers.py
index 434c5c8e63..2e95b9cf9c 100644
--- a/gapic/schema/wrappers.py
+++ b/gapic/schema/wrappers.py
@@ -56,7 +56,6 @@ class Field:
     )
     oneof: bool = False
 
-
     def __getattr__(self, name):
         return getattr(self.field_pb, name)
 

From 593f64775e7bde0e4c52a897e5e7500d4c4de44e Mon Sep 17 00:00:00 2001
From: Chris Wilcox <crwilcox@google.com>
Date: Thu, 25 Jun 2020 23:11:44 -0700
Subject: [PATCH 05/25] str type for oneof

---
 gapic/schema/wrappers.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gapic/schema/wrappers.py b/gapic/schema/wrappers.py
index 2e95b9cf9c..04d062ad7a 100644
--- a/gapic/schema/wrappers.py
+++ b/gapic/schema/wrappers.py
@@ -54,7 +54,7 @@ class Field:
     meta: metadata.Metadata = dataclasses.field(
         default_factory=metadata.Metadata,
     )
-    oneof: bool = False
+    oneof: str = None
 
     def __getattr__(self, name):
         return getattr(self.field_pb, name)

From 114a277f63656a2bea5007edfe677a40ca71cffe Mon Sep 17 00:00:00 2001
From: Chris Wilcox <crwilcox@google.com>
Date: Fri, 26 Jun 2020 09:59:48 -0700
Subject: [PATCH 06/25] add field oneof to ads templates

---
 .../%namespace/%name/%version/%sub/types/_message.py.j2          | 1 +
 1 file changed, 1 insertion(+)

diff --git a/gapic/ads-templates/%namespace/%name/%version/%sub/types/_message.py.j2 b/gapic/ads-templates/%namespace/%name/%version/%sub/types/_message.py.j2
index a8119827b8..15bf3ea4ab 100644
--- a/gapic/ads-templates/%namespace/%name/%version/%sub/types/_message.py.j2
+++ b/gapic/ads-templates/%namespace/%name/%version/%sub/types/_message.py.j2
@@ -43,6 +43,7 @@ class {{ message.name }}({{ p }}.Message):
     {% else -%}
     {{ field.name }} = {{ p }}.{% if field.repeated %}Repeated{% endif %}Field(
         {{- p }}.{{ field.proto_type }}, number={{ field.number }}
+    {% if field.oneof %}, oneof='{{ field.oneof }}'{% endif %}
     {%- if field.enum or field.message %},
         {{ field.proto_type.lower() }}={{ field.type.ident.rel(message.ident) }},
     {% endif %})

From 589e914cadac3ddcf4d6e81dc9c6c52cad83cf55 Mon Sep 17 00:00:00 2001
From: Chris Wilcox <crwilcox@google.com>
Date: Fri, 26 Jun 2020 10:04:18 -0700
Subject: [PATCH 07/25] mypy: specify oneof as optional

---
 gapic/schema/wrappers.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gapic/schema/wrappers.py b/gapic/schema/wrappers.py
index 04d062ad7a..a4add5084f 100644
--- a/gapic/schema/wrappers.py
+++ b/gapic/schema/wrappers.py
@@ -54,7 +54,7 @@ class Field:
     meta: metadata.Metadata = dataclasses.field(
         default_factory=metadata.Metadata,
     )
-    oneof: str = None
+    oneof: Optional[str] = None
 
     def __getattr__(self, name):
         return getattr(self.field_pb, name)

From c912534a8920020e4dd94bf9b13840d3a81f817b Mon Sep 17 00:00:00 2001
From: Chris Wilcox <crwilcox@google.com>
Date: Mon, 29 Jun 2020 17:04:29 -0700
Subject: [PATCH 08/25] add oneofs to schema

---
 gapic/schema/api.py      | 49 ++++++++++++++++++++++++++++++++++++----
 gapic/schema/wrappers.py | 10 ++++++++
 2 files changed, 55 insertions(+), 4 deletions(-)

diff --git a/gapic/schema/api.py b/gapic/schema/api.py
index cc9b9cf1f0..5066af1bd0 100644
--- a/gapic/schema/api.py
+++ b/gapic/schema/api.py
@@ -556,14 +556,43 @@ def _load_children(self,
             answer[wrapped.name] = wrapped
         return answer
 
+    def _get_oneofs(self,
+                    oneof_pbs: Sequence[descriptor_pb2.OneofDescriptorProto],
+                    address: metadata.Address, path: Tuple[int, ...],
+                    ) -> Dict[str, wrappers.Oneof]:
+        """Return a dictionary of wrapped oneofs for the given message.
+
+        Args:
+            oneof_fields (Sequence[~.descriptor_pb2.OneofDescriptorProto]): A
+                sequence of protobuf field objects.
+            address (~.metadata.Address): An address object denoting the
+                location of these oneofs.
+            path (Tuple[int]): The source location path thus far, as
+                understood by ``SourceCodeInfo.Location``.
+
+        Returns:
+            Mapping[str, ~.wrappers.Oneof]: A ordered mapping of
+                :class:`~.wrappers.Oneof` objects.
+        """
+        # Iterate over the oneofs and collect them into a dictionary.
+        answer: Dict[str, wrappers.Oneof] = collections.OrderedDict()
+        for oneof_pb, i in zip(oneof_pbs, range(0, sys.maxsize)):
+            answer[oneof_pb.name] = wrappers.Oneof(
+                oneof_pb=oneof_pb,
+            )
+
+        # Done; return the answer.
+        return answer
+
     def _get_fields(self,
                     field_pbs: Sequence[descriptor_pb2.FieldDescriptorProto],
                     address: metadata.Address, path: Tuple[int, ...],
+                    oneofs = None
                     ) -> Dict[str, wrappers.Field]:
         """Return a dictionary of wrapped fields for the given message.
 
         Args:
-            fields (Sequence[~.descriptor_pb2.FieldDescriptorProto]): A
+            field_pbs (Sequence[~.descriptor_pb2.FieldDescriptorProto]): A
                 sequence of protobuf field objects.
             address (~.metadata.Address): An address object denoting the
                 location of these fields.
@@ -586,14 +615,19 @@ def _get_fields(self,
         # `_load_message` method.
         answer: Dict[str, wrappers.Field] = collections.OrderedDict()
         for field_pb, i in zip(field_pbs, range(0, sys.maxsize)):
+            oneof_name = None
+            if getattr(field_pb, 'oneof_index', -1) >= 0 and oneofs:
+                    oneof_name = list(oneofs.keys())[field_pb.oneof_index]
+
             answer[field_pb.name] = wrappers.Field(
                 field_pb=field_pb,
                 enum=self.api_enums.get(field_pb.type_name.lstrip('.')),
                 message=self.api_messages.get(field_pb.type_name.lstrip('.')),
-                meta=metadata.Metadata(
+                metaexit=metadata.Metadata(
                     address=address.child(field_pb.name, path + (i,)),
                     documentation=self.docs.get(path + (i,), self.EMPTY),
                 ),
+                oneof=oneof_name,
             )
 
         # Done; return the answer.
@@ -779,19 +813,25 @@ def _load_message(self,
             loader=self._load_message,
             path=path + (3,),
         )
-        # self._load_children(message.oneof_decl, loader=self._load_field,
-        #                     address=nested_addr, info=info.get(8, {}))
+
+        oneofs = self._get_oneofs(
+            message_pb.oneof_decl,
+            address=address,
+            path=path + (8,),
+        )
 
         # Create a dictionary of all the fields for this message.
         fields = self._get_fields(
             message_pb.field,
             address=address,
             path=path + (2,),
+            oneofs=oneofs,
         )
         fields.update(self._get_fields(
             message_pb.extension,
             address=address,
             path=path + (6,),
+            oneofs=oneofs,
         ))
 
         # Create a message correspoding to this descriptor.
@@ -804,6 +844,7 @@ def _load_message(self,
                 address=address,
                 documentation=self.docs.get(path, self.EMPTY),
             ),
+            oneofs=oneofs,
         )
         return self.proto_messages[address.proto]
 
diff --git a/gapic/schema/wrappers.py b/gapic/schema/wrappers.py
index a4add5084f..7c6c5ac187 100644
--- a/gapic/schema/wrappers.py
+++ b/gapic/schema/wrappers.py
@@ -207,6 +207,15 @@ def with_context(self, *, collisions: FrozenSet[str]) -> 'Field':
         )
 
 
+@dataclasses.dataclass(frozen=True)
+class Oneof:
+    """Description of a field."""
+    oneof_pb: descriptor_pb2.OneofDescriptorProto
+
+    def __getattr__(self, name):
+        return getattr(self.oneof_pb, name)
+
+
 @dataclasses.dataclass(frozen=True)
 class MessageType:
     """Description of a message (defined with the ``message`` keyword)."""
@@ -221,6 +230,7 @@ class MessageType:
     meta: metadata.Metadata = dataclasses.field(
         default_factory=metadata.Metadata,
     )
+    oneofs: Optional[List[str]] = None
 
     def __getattr__(self, name):
         return getattr(self.message_pb, name)

From afa357835521ecfa32aab0f4038a71c42a04afd8 Mon Sep 17 00:00:00 2001
From: Chris Wilcox <crwilcox@google.com>
Date: Mon, 29 Jun 2020 17:14:05 -0700
Subject: [PATCH 09/25] exit oops

---
 gapic/schema/api.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gapic/schema/api.py b/gapic/schema/api.py
index 5066af1bd0..f8dae18418 100644
--- a/gapic/schema/api.py
+++ b/gapic/schema/api.py
@@ -623,7 +623,7 @@ def _get_fields(self,
                 field_pb=field_pb,
                 enum=self.api_enums.get(field_pb.type_name.lstrip('.')),
                 message=self.api_messages.get(field_pb.type_name.lstrip('.')),
-                metaexit=metadata.Metadata(
+                meta=metadata.Metadata(
                     address=address.child(field_pb.name, path + (i,)),
                     documentation=self.docs.get(path + (i,), self.EMPTY),
                 ),

From 9a5e6c511ed176ed46695b7228b6a1e0d1d8f387 Mon Sep 17 00:00:00 2001
From: Chris Wilcox <crwilcox@google.com>
Date: Mon, 29 Jun 2020 19:23:28 -0700
Subject: [PATCH 10/25] mypy and lint fixes

---
 gapic/schema/api.py      | 4 ++--
 gapic/schema/wrappers.py | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/gapic/schema/api.py b/gapic/schema/api.py
index f8dae18418..bfce262c99 100644
--- a/gapic/schema/api.py
+++ b/gapic/schema/api.py
@@ -587,7 +587,7 @@ def _get_oneofs(self,
     def _get_fields(self,
                     field_pbs: Sequence[descriptor_pb2.FieldDescriptorProto],
                     address: metadata.Address, path: Tuple[int, ...],
-                    oneofs = None
+                    oneofs=None
                     ) -> Dict[str, wrappers.Field]:
         """Return a dictionary of wrapped fields for the given message.
 
@@ -617,7 +617,7 @@ def _get_fields(self,
         for field_pb, i in zip(field_pbs, range(0, sys.maxsize)):
             oneof_name = None
             if getattr(field_pb, 'oneof_index', -1) >= 0 and oneofs:
-                    oneof_name = list(oneofs.keys())[field_pb.oneof_index]
+                oneof_name = list(oneofs.keys())[field_pb.oneof_index]
 
             answer[field_pb.name] = wrappers.Field(
                 field_pb=field_pb,
diff --git a/gapic/schema/wrappers.py b/gapic/schema/wrappers.py
index 7c6c5ac187..34d68655db 100644
--- a/gapic/schema/wrappers.py
+++ b/gapic/schema/wrappers.py
@@ -230,7 +230,7 @@ class MessageType:
     meta: metadata.Metadata = dataclasses.field(
         default_factory=metadata.Metadata,
     )
-    oneofs: Optional[List[str]] = None
+    oneofs: Optional[Mapping[str, 'Oneof']] = None
 
     def __getattr__(self, name):
         return getattr(self.message_pb, name)

From cf31e2a643475e0ee03d8237c1d1317657cfb1b8 Mon Sep 17 00:00:00 2001
From: Chris Wilcox <crwilcox@google.com>
Date: Tue, 30 Jun 2020 12:40:13 -0700
Subject: [PATCH 11/25] add tests for oneofs

---
 test_utils/test_utils.py                 | 13 +++++++-
 tests/unit/schema/test_api.py            | 39 ++++++++++++++++++++++++
 tests/unit/schema/wrappers/test_field.py |  7 +++++
 3 files changed, 58 insertions(+), 1 deletion(-)

diff --git a/test_utils/test_utils.py b/test_utils/test_utils.py
index 697d08e8df..89fd735142 100644
--- a/test_utils/test_utils.py
+++ b/test_utils/test_utils.py
@@ -200,6 +200,7 @@ def make_field(
     message: wrappers.MessageType = None,
     enum: wrappers.EnumType = None,
     meta: metadata.Metadata = None,
+    oneof: str = None,
     **kwargs
 ) -> wrappers.Field:
     T = desc.FieldDescriptorProto.Type
@@ -223,11 +224,13 @@ def make_field(
         number=number,
         **kwargs
     )
+
     return wrappers.Field(
         field_pb=field_pb,
         enum=enum,
         message=message,
         meta=meta or metadata.Metadata(),
+        oneof=oneof,
     )
 
 
@@ -322,20 +325,28 @@ def make_enum_pb2(
 def make_message_pb2(
         name: str,
         fields: tuple = (),
+        oneof_decl: tuple = (),
         **kwargs
 ) -> desc.DescriptorProto:
-    return desc.DescriptorProto(name=name, field=fields, **kwargs)
+    return desc.DescriptorProto(name=name, field=fields, oneof_decl=oneof_decl, **kwargs)
 
 
 def make_field_pb2(name: str, number: int,
                    type: int = 11,  # 11 == message
                    type_name: str = None,
+                   oneof_index: int = None
                    ) -> desc.FieldDescriptorProto:
     return desc.FieldDescriptorProto(
         name=name,
         number=number,
         type=type,
         type_name=type_name,
+        oneof_index=oneof_index,
+    )
+
+def make_oneof_pb2(name: str) -> desc.OneofDescriptorProto:
+    return desc.OneofDescriptorProto(
+        name=name,
     )
 
 
diff --git a/tests/unit/schema/test_api.py b/tests/unit/schema/test_api.py
index 8dc1760cd8..fb98f4bb6e 100644
--- a/tests/unit/schema/test_api.py
+++ b/tests/unit/schema/test_api.py
@@ -34,6 +34,7 @@
     make_file_pb2,
     make_message_pb2,
     make_naming,
+    make_oneof_pb2,
 )
 
 
@@ -238,6 +239,44 @@ def test_proto_keyword_fname():
         'class__.proto',
     }
 
+def test_proto_oneof():
+    # Put together a couple of minimal protos.
+    fd = (
+        make_file_pb2(
+            name='dep.proto',
+            package='google.dep',
+            messages=(make_message_pb2(name='ImportedMessage', fields=()),),
+        ),
+        make_file_pb2(
+            name='foo.proto',
+            package='google.example.v1',
+            messages=(
+                make_message_pb2(name='Foo', fields=()),
+                make_message_pb2(
+                    name='Bar',
+                    fields=(
+                        make_field_pb2(name='imported_message', number=1,
+                                   type_name='.google.dep.ImportedMessage',
+                                   oneof_index=0),
+                        make_field_pb2(
+                            name='primitive', number=2, type=1, oneof_index=0),
+                    ),
+                    oneof_decl=(
+                        make_oneof_pb2(name="value_type"),
+                    )
+                )
+            )
+        )
+    )
+
+    # Create an API with those protos.
+    api_schema = api.API.build(fd, package='google.example.v1')
+    proto = api_schema.protos['foo.proto']
+    assert proto.names == {'imported_message', 'Bar', 'primitive', 'Foo'}
+    oneofs = proto.messages["google.example.v1.Bar"].oneofs
+    assert len(oneofs) == 1
+    assert "value_type" in oneofs.keys()
+
 
 def test_proto_names_import_collision():
     # Put together a couple of minimal protos.
diff --git a/tests/unit/schema/wrappers/test_field.py b/tests/unit/schema/wrappers/test_field.py
index 7104c735be..3cdcaf9bcf 100644
--- a/tests/unit/schema/wrappers/test_field.py
+++ b/tests/unit/schema/wrappers/test_field.py
@@ -153,6 +153,13 @@ def test_mock_value_int():
     assert field.mock_value == '728'
 
 
+def test_oneof():
+    REP = descriptor_pb2.FieldDescriptorProto.Label.Value('LABEL_REPEATED')
+
+    field = make_field(oneof="oneof_name")
+    assert field.oneof == "oneof_name"
+
+
 def test_mock_value_float():
     field = make_field(name='foo_bar', type='TYPE_DOUBLE')
     assert field.mock_value == '0.728'

From 3b90426576f6dc02f82d1ae8a2392d3166637604 Mon Sep 17 00:00:00 2001
From: Chris Wilcox <crwilcox@google.com>
Date: Tue, 30 Jun 2020 12:41:42 -0700
Subject: [PATCH 12/25] lint

---
 tests/unit/schema/test_api.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tests/unit/schema/test_api.py b/tests/unit/schema/test_api.py
index fb98f4bb6e..b3f023054c 100644
--- a/tests/unit/schema/test_api.py
+++ b/tests/unit/schema/test_api.py
@@ -239,6 +239,7 @@ def test_proto_keyword_fname():
         'class__.proto',
     }
 
+
 def test_proto_oneof():
     # Put together a couple of minimal protos.
     fd = (

From 70cfe159776aacd4b47b49b60f516e2a7f7845e6 Mon Sep 17 00:00:00 2001
From: Chris Wilcox <crwilcox@google.com>
Date: Tue, 30 Jun 2020 12:50:32 -0700
Subject: [PATCH 13/25] typing and test

---
 gapic/schema/api.py                      | 11 ++++---
 tests/unit/schema/wrappers/test_oneof.py | 37 ++++++++++++++++++++++++
 2 files changed, 42 insertions(+), 6 deletions(-)
 create mode 100644 tests/unit/schema/wrappers/test_oneof.py

diff --git a/gapic/schema/api.py b/gapic/schema/api.py
index bfce262c99..3422f45d80 100644
--- a/gapic/schema/api.py
+++ b/gapic/schema/api.py
@@ -575,11 +575,10 @@ def _get_oneofs(self,
                 :class:`~.wrappers.Oneof` objects.
         """
         # Iterate over the oneofs and collect them into a dictionary.
-        answer: Dict[str, wrappers.Oneof] = collections.OrderedDict()
-        for oneof_pb, i in zip(oneof_pbs, range(0, sys.maxsize)):
-            answer[oneof_pb.name] = wrappers.Oneof(
-                oneof_pb=oneof_pb,
-            )
+        answer = collections.OrderedDict(
+            (oneof_pb.name, wrappers.Oneof(oneof_pb=oneof_pb))
+            for i, oneof_pb in enumerate(oneof_pbs)
+        )
 
         # Done; return the answer.
         return answer
@@ -587,7 +586,7 @@ def _get_oneofs(self,
     def _get_fields(self,
                     field_pbs: Sequence[descriptor_pb2.FieldDescriptorProto],
                     address: metadata.Address, path: Tuple[int, ...],
-                    oneofs=None
+                    oneofs: Optional[Dict[str, wrappers.Oneof]]=None
                     ) -> Dict[str, wrappers.Field]:
         """Return a dictionary of wrapped fields for the given message.
 
diff --git a/tests/unit/schema/wrappers/test_oneof.py b/tests/unit/schema/wrappers/test_oneof.py
new file mode 100644
index 0000000000..d772846e12
--- /dev/null
+++ b/tests/unit/schema/wrappers/test_oneof.py
@@ -0,0 +1,37 @@
+# Copyright 2018 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import collections
+
+import pytest
+
+from google.api import field_behavior_pb2
+from google.protobuf import descriptor_pb2
+
+from gapic.schema import metadata
+from gapic.schema import wrappers
+
+from test_utils.test_utils import (
+    #make_field,
+    #make_message,
+    make_oneof_pb2,
+)
+
+
+def test_wrapped_oneof():
+    oneof_pb = make_oneof_pb2("oneof_name")
+    wrapped = wrappers.Oneof(oneof_pb=oneof_pb)
+
+    assert wrapped.oneof_pb == oneof_pb
+    assert wrapped.name == oneof_pb.name

From 58d3f97a807699363ad7e79dc08ebfdb994d2afd Mon Sep 17 00:00:00 2001
From: Chris Wilcox <crwilcox@google.com>
Date: Tue, 30 Jun 2020 12:53:33 -0700
Subject: [PATCH 14/25] style

---
 gapic/schema/api.py                      | 2 +-
 tests/unit/schema/wrappers/test_oneof.py | 2 --
 2 files changed, 1 insertion(+), 3 deletions(-)

diff --git a/gapic/schema/api.py b/gapic/schema/api.py
index 3422f45d80..3da8c2cb0c 100644
--- a/gapic/schema/api.py
+++ b/gapic/schema/api.py
@@ -586,7 +586,7 @@ def _get_oneofs(self,
     def _get_fields(self,
                     field_pbs: Sequence[descriptor_pb2.FieldDescriptorProto],
                     address: metadata.Address, path: Tuple[int, ...],
-                    oneofs: Optional[Dict[str, wrappers.Oneof]]=None
+                    oneofs: Optional[Dict[str, wrappers.Oneof]] = None 
                     ) -> Dict[str, wrappers.Field]:
         """Return a dictionary of wrapped fields for the given message.
 
diff --git a/tests/unit/schema/wrappers/test_oneof.py b/tests/unit/schema/wrappers/test_oneof.py
index d772846e12..90fe2546ce 100644
--- a/tests/unit/schema/wrappers/test_oneof.py
+++ b/tests/unit/schema/wrappers/test_oneof.py
@@ -23,8 +23,6 @@
 from gapic.schema import wrappers
 
 from test_utils.test_utils import (
-    #make_field,
-    #make_message,
     make_oneof_pb2,
 )
 

From b44317f504735049868d74facf97c278c1ecc13a Mon Sep 17 00:00:00 2001
From: Chris Wilcox <crwilcox@google.com>
Date: Tue, 30 Jun 2020 12:57:36 -0700
Subject: [PATCH 15/25] whitespace

---
 gapic/schema/api.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gapic/schema/api.py b/gapic/schema/api.py
index 3da8c2cb0c..6c666d6980 100644
--- a/gapic/schema/api.py
+++ b/gapic/schema/api.py
@@ -586,7 +586,7 @@ def _get_oneofs(self,
     def _get_fields(self,
                     field_pbs: Sequence[descriptor_pb2.FieldDescriptorProto],
                     address: metadata.Address, path: Tuple[int, ...],
-                    oneofs: Optional[Dict[str, wrappers.Oneof]] = None 
+                    oneofs: Optional[Dict[str, wrappers.Oneof]] = None
                     ) -> Dict[str, wrappers.Field]:
         """Return a dictionary of wrapped fields for the given message.
 

From 374bfbe05563560d31a93874f3bbd56b989c4337 Mon Sep 17 00:00:00 2001
From: Dov Shlachter <dovs@google.com>
Date: Mon, 6 Jul 2020 14:02:37 -0700
Subject: [PATCH 16/25] Add an nth utility

---
 gapic/utils/__init__.py |  2 ++
 gapic/utils/code.py     | 16 ++++++++++++++--
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/gapic/utils/__init__.py b/gapic/utils/__init__.py
index 315c575e2b..905fcbdec2 100644
--- a/gapic/utils/__init__.py
+++ b/gapic/utils/__init__.py
@@ -15,6 +15,7 @@
 from gapic.utils.cache import cached_property
 from gapic.utils.case import to_snake_case
 from gapic.utils.code import empty
+from gapic.utils.code import nth
 from gapic.utils.code import partition
 from gapic.utils.doc import doc
 from gapic.utils.filename import to_valid_filename
@@ -29,6 +30,7 @@
     'cached_property',
     'doc',
     'empty',
+    'nth',
     'partition',
     'RESERVED_NAMES',
     'rst',
diff --git a/gapic/utils/code.py b/gapic/utils/code.py
index 27458a999c..00b7d4d170 100644
--- a/gapic/utils/code.py
+++ b/gapic/utils/code.py
@@ -12,8 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from typing import (Callable, Iterable, List, Tuple, TypeVar)
-
+from typing import (Callable, Iterable, List, Optional, Tuple, TypeVar)
+import itertools
 
 def empty(content: str) -> bool:
     """Return True if this file has no Python statements, False otherwise.
@@ -50,3 +50,15 @@ def partition(predicate: Callable[[T], bool],
 
     # Returns trueList, falseList
     return results[1], results[0]
+
+
+def nth(iterable: Iterable[T], n: int, default: Optional[T]=None) -> Optional[T]:
+    """Return the nth element of an iterable or a default value.
+
+    Args
+        iterable: (Iterable(T)): An iterable on any type.
+        n (int):                 The 'index' of the lement to retrieve.
+        default: (Optional(T)):  An optional default elemnt if the iterable has
+                                 fewer than n elements.
+    """
+    return next(itertools.islice(iterable, n, None), default)

From a329bd09d3a042474ea0b5b9e3dbe83004dc4643 Mon Sep 17 00:00:00 2001
From: Dov Shlachter <dovs@google.com>
Date: Mon, 6 Jul 2020 14:03:08 -0700
Subject: [PATCH 17/25] Tweak api.py to use nth

---
 gapic/schema/api.py | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/gapic/schema/api.py b/gapic/schema/api.py
index 6c666d6980..a94f1c1fef 100644
--- a/gapic/schema/api.py
+++ b/gapic/schema/api.py
@@ -34,6 +34,7 @@
 from gapic.schema import wrappers
 from gapic.schema import naming as api_naming
 from gapic.utils import cached_property
+from gapic.utils import nth
 from gapic.utils import to_snake_case
 from gapic.utils import RESERVED_NAMES
 
@@ -614,9 +615,8 @@ def _get_fields(self,
         # `_load_message` method.
         answer: Dict[str, wrappers.Field] = collections.OrderedDict()
         for field_pb, i in zip(field_pbs, range(0, sys.maxsize)):
-            oneof_name = None
-            if getattr(field_pb, 'oneof_index', -1) >= 0 and oneofs:
-                oneof_name = list(oneofs.keys())[field_pb.oneof_index]
+            oneofs_exist = oneofs and getattr(field_pb, 'oneof_index', -1) > 0
+            oneof_name = nth(oneofs, field_pb.oneof_index) if oneofs_exist else None
 
             answer[field_pb.name] = wrappers.Field(
                 field_pb=field_pb,
@@ -816,7 +816,7 @@ def _load_message(self,
         oneofs = self._get_oneofs(
             message_pb.oneof_decl,
             address=address,
-            path=path + (8,),
+            path=path + (7,),
         )
 
         # Create a dictionary of all the fields for this message.

From cbf73a3b6e20e6771c14373652784f69db47e274 Mon Sep 17 00:00:00 2001
From: Dov Shlachter <dovs@google.com>
Date: Mon, 6 Jul 2020 14:03:30 -0700
Subject: [PATCH 18/25] Templates change for oneofs (NOT ADS TEMPLATES)

---
 gapic/templates/noxfile.py.j2                       |  2 +-
 .../gapic/%name_%version/%sub/test_%service.py.j2   | 13 ++++++++-----
 2 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/gapic/templates/noxfile.py.j2 b/gapic/templates/noxfile.py.j2
index d31a325e2f..5fde488f00 100644
--- a/gapic/templates/noxfile.py.j2
+++ b/gapic/templates/noxfile.py.j2
@@ -20,7 +20,7 @@ def unit(session):
         '--cov-config=.coveragerc',
         '--cov-report=term',
         '--cov-report=html',
-        os.path.join('tests', 'unit', '{{ api.naming.versioned_module_name }}'),
+        os.path.join('tests', 'unit',)
     )
 
 
diff --git a/gapic/templates/tests/unit/gapic/%name_%version/%sub/test_%service.py.j2 b/gapic/templates/tests/unit/gapic/%name_%version/%sub/test_%service.py.j2
index ecfe6af704..45355276d9 100644
--- a/gapic/templates/tests/unit/gapic/%name_%version/%sub/test_%service.py.j2
+++ b/gapic/templates/tests/unit/gapic/%name_%version/%sub/test_%service.py.j2
@@ -285,9 +285,9 @@ def test_{{ method.name|snake_case }}(transport: str = 'grpc'):
         call.return_value = iter([{{ method.output.ident }}()])
         {% else -%}
         call.return_value = {{ method.output.ident }}(
-            {%- for field in method.output.fields.values() | rejectattr('message') %}
+            {%- for field in method.output.fields.values() | rejectattr('message')%}{% if not (field.oneof and not field.proto3_optional) %}
             {{ field.name }}={{ field.mock_value }},
-            {%- endfor %}
+            {% endif %}{%- endfor %}
         )
         {% endif -%}
         {% if method.client_streaming %}
@@ -315,7 +315,7 @@ def test_{{ method.name|snake_case }}(transport: str = 'grpc'):
         assert isinstance(message, {{ method.output.ident }})
     {% else -%}
     assert isinstance(response, {{ method.client_output.ident }})
-    {% for field in method.output.fields.values() | rejectattr('message') -%}
+    {% for field in method.output.fields.values() | rejectattr('message') -%}{% if not (field.oneof and not field.proto3_optional) %}
     {% if field.field_pb.type in [1, 2] -%} {# Use approx eq for floats -#}
     assert math.isclose(response.{{ field.name }}, {{ field.mock_value }}, rel_tol=1e-6)
     {% elif field.field_pb.type == 8 -%} {# Use 'is' for bools #}
@@ -323,6 +323,7 @@ def test_{{ method.name|snake_case }}(transport: str = 'grpc'):
     {% else -%}
     assert response.{{ field.name }} == {{ field.mock_value }}
     {% endif -%}
+    {% endif -%} {# end oneof/optional #}
     {% endfor %}
     {% endif %}
 
@@ -365,8 +366,9 @@ async def test_{{ method.name|snake_case }}_async(transport: str = 'grpc_asyncio
             {%- else -%}
                 grpc_helpers_async.FakeStreamUnaryCall
             {%- endif -%}({{ method.output.ident }}(
-            {%- for field in method.output.fields.values() | rejectattr('message') %}
+            {%- for field in method.output.fields.values() | rejectattr('message') %}{% if not (field.oneof and not field.proto3_optional) %}
             {{ field.name }}={{ field.mock_value }},
+            {%- endif %}
             {%- endfor %}
         ))
         {% endif -%}
@@ -397,7 +399,7 @@ async def test_{{ method.name|snake_case }}_async(transport: str = 'grpc_asyncio
     assert isinstance(message, {{ method.output.ident }})
     {% else -%}
     assert isinstance(response, {{ method.client_output_async.ident }})
-    {% for field in method.output.fields.values() | rejectattr('message') -%}
+    {% for field in method.output.fields.values() | rejectattr('message') -%}{% if not (field.oneof and not field.proto3_optional) %}
     {% if field.field_pb.type in [1, 2] -%} {# Use approx eq for floats -#}
     assert math.isclose(response.{{ field.name }}, {{ field.mock_value }}, rel_tol=1e-6)
     {% elif field.field_pb.type == 8 -%} {# Use 'is' for bools #}
@@ -405,6 +407,7 @@ async def test_{{ method.name|snake_case }}_async(transport: str = 'grpc_asyncio
     {% else -%}
     assert response.{{ field.name }} == {{ field.mock_value }}
     {% endif -%}
+    {% endif -%} {# oneof/optional #}
     {% endfor %}
     {% endif %}
 

From 5f861d3ddd239afaa749c0b6ffe4148f10874f5a Mon Sep 17 00:00:00 2001
From: Dov Shlachter <dovs@google.com>
Date: Tue, 7 Jul 2020 13:25:51 -0700
Subject: [PATCH 19/25] Test nth

---
 gapic/schema/api.py           | 2 +-
 tests/unit/utils/test_code.py | 8 ++++++++
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/gapic/schema/api.py b/gapic/schema/api.py
index a94f1c1fef..8ec70f422b 100644
--- a/gapic/schema/api.py
+++ b/gapic/schema/api.py
@@ -614,7 +614,7 @@ def _get_fields(self,
         # first) and this will be None. This case is addressed in the
         # `_load_message` method.
         answer: Dict[str, wrappers.Field] = collections.OrderedDict()
-        for field_pb, i in zip(field_pbs, range(0, sys.maxsize)):
+        for i, field_pb in enumerate(field_pbs):
             oneofs_exist = oneofs and getattr(field_pb, 'oneof_index', -1) > 0
             oneof_name = nth(oneofs, field_pb.oneof_index) if oneofs_exist else None
 
diff --git a/tests/unit/utils/test_code.py b/tests/unit/utils/test_code.py
index 1069443f7b..b0106073d5 100644
--- a/tests/unit/utils/test_code.py
+++ b/tests/unit/utils/test_code.py
@@ -34,3 +34,11 @@ def test_empty_whitespace_comments():
 
 def test_empty_code():
     assert not code.empty('import this')
+
+def test_nth():
+    # list
+    assert code.nth([i*i for i in range(20)], 4) == 16
+    # generator
+    assert code.nth((i*i for i in range(20)), 4) == 16
+    # default
+    assert code.nth((i*i for i in range(20)), 30, 2112) == 2112

From 64ec32b4b2072198a72e41319b23f73dd340b25c Mon Sep 17 00:00:00 2001
From: Dov Shlachter <dovs@google.com>
Date: Tue, 7 Jul 2020 13:27:39 -0700
Subject: [PATCH 20/25] Style check

---
 gapic/schema/api.py           | 3 ++-
 gapic/utils/code.py           | 3 ++-
 tests/unit/utils/test_code.py | 6 +++---
 3 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/gapic/schema/api.py b/gapic/schema/api.py
index 8ec70f422b..5823787f59 100644
--- a/gapic/schema/api.py
+++ b/gapic/schema/api.py
@@ -616,7 +616,8 @@ def _get_fields(self,
         answer: Dict[str, wrappers.Field] = collections.OrderedDict()
         for i, field_pb in enumerate(field_pbs):
             oneofs_exist = oneofs and getattr(field_pb, 'oneof_index', -1) > 0
-            oneof_name = nth(oneofs, field_pb.oneof_index) if oneofs_exist else None
+            oneof_name = nth(oneofs,
+                             field_pb.oneof_index) if oneofs_exist else None
 
             answer[field_pb.name] = wrappers.Field(
                 field_pb=field_pb,
diff --git a/gapic/utils/code.py b/gapic/utils/code.py
index 00b7d4d170..2c8d869392 100644
--- a/gapic/utils/code.py
+++ b/gapic/utils/code.py
@@ -15,6 +15,7 @@
 from typing import (Callable, Iterable, List, Optional, Tuple, TypeVar)
 import itertools
 
+
 def empty(content: str) -> bool:
     """Return True if this file has no Python statements, False otherwise.
 
@@ -52,7 +53,7 @@ def partition(predicate: Callable[[T], bool],
     return results[1], results[0]
 
 
-def nth(iterable: Iterable[T], n: int, default: Optional[T]=None) -> Optional[T]:
+def nth(iterable: Iterable[T], n: int, default: Optional[T] = None) -> Optional[T]:
     """Return the nth element of an iterable or a default value.
 
     Args
diff --git a/tests/unit/utils/test_code.py b/tests/unit/utils/test_code.py
index b0106073d5..fe77d4314a 100644
--- a/tests/unit/utils/test_code.py
+++ b/tests/unit/utils/test_code.py
@@ -37,8 +37,8 @@ def test_empty_code():
 
 def test_nth():
     # list
-    assert code.nth([i*i for i in range(20)], 4) == 16
+    assert code.nth([i * i for i in range(20)], 4) == 16
     # generator
-    assert code.nth((i*i for i in range(20)), 4) == 16
+    assert code.nth((i * i for i in range(20)), 4) == 16
     # default
-    assert code.nth((i*i for i in range(20)), 30, 2112) == 2112
+    assert code.nth((i * i for i in range(20)), 30, 2112) == 2112

From 07709f871fe0b02f3f7e29738a7a5b65ae773f02 Mon Sep 17 00:00:00 2001
From: Dov Shlachter <dovs@google.com>
Date: Tue, 7 Jul 2020 13:36:34 -0700
Subject: [PATCH 21/25] Tweak

---
 gapic/schema/api.py           | 8 +++++---
 tests/unit/utils/test_code.py | 1 +
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/gapic/schema/api.py b/gapic/schema/api.py
index 5823787f59..d22dbe4980 100644
--- a/gapic/schema/api.py
+++ b/gapic/schema/api.py
@@ -615,9 +615,11 @@ def _get_fields(self,
         # `_load_message` method.
         answer: Dict[str, wrappers.Field] = collections.OrderedDict()
         for i, field_pb in enumerate(field_pbs):
-            oneofs_exist = oneofs and getattr(field_pb, 'oneof_index', -1) > 0
-            oneof_name = nth(oneofs,
-                             field_pb.oneof_index) if oneofs_exist else None
+            oneof_name = nth(
+                iter(oneofs or {}),
+                field_pb.oneof_index if getattr(field_pb, 'oneof_index', -1) > 0 else None,
+                None
+            )
 
             answer[field_pb.name] = wrappers.Field(
                 field_pb=field_pb,
diff --git a/tests/unit/utils/test_code.py b/tests/unit/utils/test_code.py
index fe77d4314a..5f18679d6f 100644
--- a/tests/unit/utils/test_code.py
+++ b/tests/unit/utils/test_code.py
@@ -35,6 +35,7 @@ def test_empty_whitespace_comments():
 def test_empty_code():
     assert not code.empty('import this')
 
+
 def test_nth():
     # list
     assert code.nth([i * i for i in range(20)], 4) == 16

From aa7ceb625826c029bf10c30c704e1cc8e2044bc5 Mon Sep 17 00:00:00 2001
From: Dov Shlachter <dovs@google.com>
Date: Tue, 7 Jul 2020 13:39:34 -0700
Subject: [PATCH 22/25] Thing

---
 gapic/schema/api.py | 6 +++++-
 gapic/utils/code.py | 8 ++++----
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/gapic/schema/api.py b/gapic/schema/api.py
index d22dbe4980..30dbac3943 100644
--- a/gapic/schema/api.py
+++ b/gapic/schema/api.py
@@ -617,7 +617,11 @@ def _get_fields(self,
         for i, field_pb in enumerate(field_pbs):
             oneof_name = nth(
                 iter(oneofs or {}),
-                field_pb.oneof_index if getattr(field_pb, 'oneof_index', -1) > 0 else None,
+                field_pb.oneof_index if getattr(
+                    field_pb,
+                    'oneof_index',
+                    -1
+                ) > 0 else None,
                 None
             )
 
diff --git a/gapic/utils/code.py b/gapic/utils/code.py
index 2c8d869392..87603e215e 100644
--- a/gapic/utils/code.py
+++ b/gapic/utils/code.py
@@ -53,13 +53,13 @@ def partition(predicate: Callable[[T], bool],
     return results[1], results[0]
 
 
-def nth(iterable: Iterable[T], n: int, default: Optional[T] = None) -> Optional[T]:
+def nth(iterable: Iterable[T], n: Optional[int] = None, default: Optional[T] = None) -> Optional[T]:
     """Return the nth element of an iterable or a default value.
 
     Args
-        iterable: (Iterable(T)): An iterable on any type.
-        n (int):                 The 'index' of the lement to retrieve.
-        default: (Optional(T)):  An optional default elemnt if the iterable has
+        iterable (Iterable(T)): An iterable on any type.
+        n (Optional(int)):      The 'index' of the lement to retrieve.
+        default (Optional(T)):  An optional default elemnt if the iterable has
                                  fewer than n elements.
     """
     return next(itertools.islice(iterable, n, None), default)

From ec65b735c827668d89ade8ee43fbcff757d0a313 Mon Sep 17 00:00:00 2001
From: Dov Shlachter <dovs@google.com>
Date: Tue, 7 Jul 2020 14:31:34 -0700
Subject: [PATCH 23/25] Thing in thing exception

---
 gapic/schema/api.py                                | 14 +++++---------
 .../%name_%version/%sub/types/_message.py.j2       | 10 +++++-----
 gapic/utils/code.py                                |  4 ++--
 3 files changed, 12 insertions(+), 16 deletions(-)

diff --git a/gapic/schema/api.py b/gapic/schema/api.py
index 30dbac3943..67efad53c5 100644
--- a/gapic/schema/api.py
+++ b/gapic/schema/api.py
@@ -615,16 +615,12 @@ def _get_fields(self,
         # `_load_message` method.
         answer: Dict[str, wrappers.Field] = collections.OrderedDict()
         for i, field_pb in enumerate(field_pbs):
+            is_oneof = oneofs and field_pb.oneof_index > 0
             oneof_name = nth(
-                iter(oneofs or {}),
-                field_pb.oneof_index if getattr(
-                    field_pb,
-                    'oneof_index',
-                    -1
-                ) > 0 else None,
-                None
-            )
-
+                iter(oneofs),
+                field_pb.oneof_index
+            ) if is_oneof else None
+            
             answer[field_pb.name] = wrappers.Field(
                 field_pb=field_pb,
                 enum=self.api_enums.get(field_pb.type_name.lstrip('.')),
diff --git a/gapic/templates/%namespace/%name_%version/%sub/types/_message.py.j2 b/gapic/templates/%namespace/%name_%version/%sub/types/_message.py.j2
index e71ea0f70f..5a1eb5fcc6 100644
--- a/gapic/templates/%namespace/%name_%version/%sub/types/_message.py.j2
+++ b/gapic/templates/%namespace/%name_%version/%sub/types/_message.py.j2
@@ -38,15 +38,15 @@ class {{ message.name }}({{ p }}.Message):
         {{- p }}.{{ key_field.proto_type }}, {{ p }}.{{ value_field.proto_type }}, number={{ field.number }}
     {%- if value_field.enum or value_field.message %},
         {{ value_field.proto_type.lower() }}={{ value_field.type.ident.rel(message.ident) }},
-    {% endif %})
+    {% endif %})                {# enum or message#}
     {% endwith -%}
-    {% else -%}
+    {% else -%}                 {# field.map #}
     {{ field.name }} = {{ p }}.{% if field.repeated %}Repeated{% endif %}Field(
         {{- p }}.{{ field.proto_type }}, number={{ field.number }}
     {% if field.oneof %}, oneof='{{ field.oneof }}'{% endif %}
     {%- if field.enum or field.message %},
         {{ field.proto_type.lower() }}={{ field.type.ident.rel(message.ident) }},
-    {% endif %})
-    {% endif -%}
-    {% endfor -%}
+    {% endif %})                {# enum or message #}
+    {% endif -%}                {# field.map #}
+    {% endfor -%} {# for field in message.fields.values#}
 {{ '\n\n' }}
diff --git a/gapic/utils/code.py b/gapic/utils/code.py
index 87603e215e..15f327983c 100644
--- a/gapic/utils/code.py
+++ b/gapic/utils/code.py
@@ -53,12 +53,12 @@ def partition(predicate: Callable[[T], bool],
     return results[1], results[0]
 
 
-def nth(iterable: Iterable[T], n: Optional[int] = None, default: Optional[T] = None) -> Optional[T]:
+def nth(iterable: Iterable[T], n: int, default: Optional[T] = None) -> Optional[T]:
     """Return the nth element of an iterable or a default value.
 
     Args
         iterable (Iterable(T)): An iterable on any type.
-        n (Optional(int)):      The 'index' of the lement to retrieve.
+        n (int):                The 'index' of the lement to retrieve.
         default (Optional(T)):  An optional default elemnt if the iterable has
                                  fewer than n elements.
     """

From 05b05d55c6be82d35130709cce344283196354ca Mon Sep 17 00:00:00 2001
From: Dov Shlachter <dovs@google.com>
Date: Tue, 7 Jul 2020 14:34:42 -0700
Subject: [PATCH 24/25] Whitespace

---
 gapic/schema/api.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gapic/schema/api.py b/gapic/schema/api.py
index 67efad53c5..e75258bc06 100644
--- a/gapic/schema/api.py
+++ b/gapic/schema/api.py
@@ -620,7 +620,7 @@ def _get_fields(self,
                 iter(oneofs),
                 field_pb.oneof_index
             ) if is_oneof else None
-            
+
             answer[field_pb.name] = wrappers.Field(
                 field_pb=field_pb,
                 enum=self.api_enums.get(field_pb.type_name.lstrip('.')),

From e590edb99452ce4d65bd0aac4613bef457a95a13 Mon Sep 17 00:00:00 2001
From: Dov Shlachter <dovs@google.com>
Date: Tue, 7 Jul 2020 14:35:21 -0700
Subject: [PATCH 25/25] Fighting the type system

---
 gapic/schema/api.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gapic/schema/api.py b/gapic/schema/api.py
index e75258bc06..df3e1daa8e 100644
--- a/gapic/schema/api.py
+++ b/gapic/schema/api.py
@@ -617,7 +617,7 @@ def _get_fields(self,
         for i, field_pb in enumerate(field_pbs):
             is_oneof = oneofs and field_pb.oneof_index > 0
             oneof_name = nth(
-                iter(oneofs),
+                (oneofs or {}).keys(),
                 field_pb.oneof_index
             ) if is_oneof else None