diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 7b578d55d985..e580ab5860c7 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -41,7 +41,7 @@ jobs:
           - os: ubuntu-latest
             ruby: "4.0"
             # (b/515549177): Disabled linkinator globally due to broken external doc links.
-            task: "--rubocop-toplevel --rubocop --build --yard"
+            task: "--rubocop-toplevel --rubocop --build --yard --doctest"
           - os: macos-latest
             ruby: "4.0"
             task: "--test"
diff --git a/.toys/.lib/sample_loader.rb b/.toys/.lib/sample_loader.rb
index ebbe40252232..7f5dbcd261d5 100644
--- a/.toys/.lib/sample_loader.rb
+++ b/.toys/.lib/sample_loader.rb
@@ -214,7 +214,7 @@ def run **params
     private
 
     def camelize name
-      ::File.basename(name, ".rb").split("_").map(&:capitalize).join
+      ::File.basename(name, ".rb").split(/[_-]/).map(&:capitalize).join
     end
 
     def traverse_name mod, name, type
diff --git a/.toys/ci.rb b/.toys/ci.rb
index a1cd344821c7..266c92c025cd 100644
--- a/.toys/ci.rb
+++ b/.toys/ci.rb
@@ -19,14 +19,15 @@
   "rubocop",
   "build",
   "yard",
+  "doctest",
   "linkinator",
   "acceptance",
   "conformance",
   "samples-main",
   "samples-latest",
 ].freeze
-OPTIONAL_TASKS = ["conformance"].freeze
-ISSUE_TASKS = ["bundle", "test", "rubocop", "build", "yard", "linkinator"].freeze
+OPTIONAL_TASKS = ["conformance", "doctest"].freeze
+ISSUE_TASKS = ["bundle", "test", "rubocop", "build", "yard", "doctest", "linkinator"].freeze
 FAILURES_REPORT_PATH = "tmp/ci-failures.json"
 
 desc "Run CI tasks."
diff --git a/google-cloud-bigquery/support/doctest_helper.rb b/google-cloud-bigquery/support/doctest_helper.rb
index 1ed1a55ad125..2d1eb6c6ff8a 100644
--- a/google-cloud-bigquery/support/doctest_helper.rb
+++ b/google-cloud-bigquery/support/doctest_helper.rb
@@ -13,6 +13,8 @@
 # limitations under the License.
 
 require "minitest/focus"
+require "minitest/mock"
+require "ostruct"
 
 require "google/cloud/bigquery"
 require "google/cloud/storage"
diff --git a/google-cloud-bigtable/support/doctest_helper.rb b/google-cloud-bigtable/support/doctest_helper.rb
index e82be8cbc9e1..7f05cef29e1c 100644
--- a/google-cloud-bigtable/support/doctest_helper.rb
+++ b/google-cloud-bigtable/support/doctest_helper.rb
@@ -13,6 +13,8 @@
 # limitations under the License.
 
 require "minitest/focus"
+require "minitest/mock"
+require "ostruct"
 
 require "google/cloud/bigtable"
 require "grpc/errors"
diff --git a/google-cloud-datastore/support/doctest_helper.rb b/google-cloud-datastore/support/doctest_helper.rb
index 8610c934afa8..054242cdeb67 100644
--- a/google-cloud-datastore/support/doctest_helper.rb
+++ b/google-cloud-datastore/support/doctest_helper.rb
@@ -13,6 +13,8 @@
 # limitations under the License.
 
 require "minitest/focus"
+require "minitest/mock"
+require "ostruct"
 
 require "grpc"
 require "google/cloud/datastore"
diff --git a/google-cloud-dns/support/doctest_helper.rb b/google-cloud-dns/support/doctest_helper.rb
index d19752acddf0..1566bc95c775 100644
--- a/google-cloud-dns/support/doctest_helper.rb
+++ b/google-cloud-dns/support/doctest_helper.rb
@@ -13,6 +13,8 @@
 # limitations under the License.
 
 require "minitest/focus"
+require "minitest/mock"
+require "ostruct"
 
 require "google/cloud/dns"
 
diff --git a/google-cloud-error_reporting/support/doctest_helper.rb b/google-cloud-error_reporting/support/doctest_helper.rb
index 38392f631381..354debf796db 100644
--- a/google-cloud-error_reporting/support/doctest_helper.rb
+++ b/google-cloud-error_reporting/support/doctest_helper.rb
@@ -13,6 +13,7 @@
 # limitations under the License.
 
 require "minitest/focus"
+require "minitest/mock"
 require "ostruct"
 
 require "google/cloud/error_reporting"
diff --git a/google-cloud-firestore/support/doctest_helper.rb b/google-cloud-firestore/support/doctest_helper.rb
index 803fe40606b9..c2a08a3dcdfb 100644
--- a/google-cloud-firestore/support/doctest_helper.rb
+++ b/google-cloud-firestore/support/doctest_helper.rb
@@ -13,6 +13,8 @@
 # limitations under the License.
 
 require "minitest/focus"
+require "minitest/mock"
+require "ostruct"
 
 require "google/cloud/firestore"
 
@@ -64,7 +66,9 @@ def on_error &block
         def last_error
         end
       end
+      remove_const :DocumentListener if const_defined? :DocumentListener
       DocumentListener = StubbedListener
+      remove_const :QueryListener if const_defined? :QueryListener
       QueryListener = StubbedListener
     end
   end
@@ -89,6 +93,11 @@ def mock_firestore
   doctest.skip "Google::Cloud::Firestore::V1::FirestoreClient"
   doctest.skip "Google::Cloud::Firestore::V1beta1::FirestoreClient"
   doctest.skip "Google::Cloud::Firestore::Admin::V1::FirestoreAdminClient"
+  doctest.skip "#listen"
+  doctest.skip "#on_snapshot"
+  doctest.skip "Listener"
+  doctest.skip "Watch"
+  doctest.skip "Google::Cloud::Firestore::BulkWriter"
 
   doctest.before "Google::Cloud#firestore" do
     mock_firestore
diff --git a/google-cloud-logging/support/doctest_helper.rb b/google-cloud-logging/support/doctest_helper.rb
index fdaab0f0d112..acf18dfddd91 100644
--- a/google-cloud-logging/support/doctest_helper.rb
+++ b/google-cloud-logging/support/doctest_helper.rb
@@ -13,6 +13,8 @@
 # limitations under the License.
 
 require "minitest/focus"
+require "minitest/mock"
+require "ostruct"
 
 require "google/cloud/storage"
 require "google/cloud/logging"
diff --git a/google-cloud-pubsub/support/doctest_helper.rb b/google-cloud-pubsub/support/doctest_helper.rb
index 53cee2b7f396..6c0b6594b174 100644
--- a/google-cloud-pubsub/support/doctest_helper.rb
+++ b/google-cloud-pubsub/support/doctest_helper.rb
@@ -13,6 +13,7 @@
 # limitations under the License.
 
 require "minitest/focus"
+require "minitest/mock"
 require "ostruct"
 
 require "google/cloud/pubsub"
@@ -67,7 +68,7 @@ def stop! *_args
 def mock_pubsub
   Google::Cloud::PubSub.stub_new do |*args|
     credentials = OpenStruct.new(client: OpenStruct.new(updater_proc: Proc.new {}))
-    pubsub = Google::Cloud::PubSub::Project.new(Google::Cloud::PubSub::Service.new("my-project", credentials))
+    pubsub = Google::Cloud::PubSub::Project.new(Google::Cloud::PubSub::Service.new("my-project", credentials, logger: Google::Cloud::PubSub::InternalLogger.new(nil)))
 
     pubsub.service.mocked_topic_admin = Minitest::Mock.new
     pubsub.service.mocked_subscription_admin = Minitest::Mock.new
@@ -94,14 +95,14 @@ def mock_pubsub
 
   doctest.before "Google::Cloud" do
     mock_pubsub do |mock_topic_admin, mock_subscription_admin|
-      mock_topic_admin.expect :publish, OpenStruct.new(message_ids: ["1"]), [Hash]
+      mock_topic_admin.expect :publish_internal, OpenStruct.new(message_ids: ["1"]), [Hash]
       mock_topic_admin.expect :get_topic, topic_resp, topic: topic_path("my-topic")
     end
   end
 
   doctest.before "Google::Cloud::PubSub" do
     mock_pubsub do |mock_topic_admin, mock_subscription_admin|
-      mock_topic_admin.expect :publish, OpenStruct.new(message_ids: ["1"]), [Hash]
+      mock_topic_admin.expect :publish_internal, OpenStruct.new(message_ids: ["1"]), [Hash]
       mock_topic_admin.expect :get_topic, topic_resp, topic: topic_path("my-topic")
     end
   end
@@ -110,7 +111,7 @@ def mock_pubsub
 
   doctest.before "Google::Cloud::PubSub::Message" do
     mock_pubsub do |mock_topic_admin, mock_subscription_admin|
-      mock_topic_admin.expect :publish, OpenStruct.new(message_ids: ["1"]), [Hash]
+      mock_topic_admin.expect :publish_internal, OpenStruct.new(message_ids: ["1"]), [Hash]
       mock_topic_admin.expect :get_topic, topic_resp, topic: topic_path("my-topic")
       mock_subscription_admin.expect :get_subscription, subscription_resp, subscription: subscription_path("my-topic-sub")
       mock_subscription_admin.expect :streaming_pull, [OpenStruct.new(received_messages: [Google::Cloud::PubSub::V1::ReceivedMessage.new(ack_id: "2", message: pubsub_message)])].to_enum, [Enumerator, Hash]
@@ -125,7 +126,7 @@ def mock_pubsub
 
   doctest.before "Google::Cloud::PubSub::Project" do
     mock_pubsub do |mock_topic_admin, mock_subscription_admin|
-      mock_topic_admin.expect :publish, OpenStruct.new(message_ids: ["1"]), [Hash]
+      mock_topic_admin.expect :publish_internal, OpenStruct.new(message_ids: ["1"]), [Hash]
       mock_topic_admin.expect :get_topic, topic_resp, topic: topic_path("my-topic")
     end
   end
@@ -140,7 +141,7 @@ def mock_pubsub
       mock_subscription_admin.expect :streaming_pull, [].to_enum, [Enumerator, Hash]
       mock_subscription_admin.expect :streaming_pull, [].to_enum, [Enumerator, Hash]
       mock_subscription_admin.expect :streaming_pull, [].to_enum, [Enumerator, Hash]
-      mock_subscription_admin.expect :acknowledge, nil, ["projects/my-project/subscriptions/my-sub", ["2"], Hash]
+      mock_subscription_admin.expect :acknowledge_internal, nil, ["projects/my-project/subscriptions/my-sub", ["2"], Hash]
     end
   end
 
@@ -165,14 +166,14 @@ def mock_pubsub
       mock_subscription_admin.expect :streaming_pull, [].to_enum, [Enumerator, Hash]
       mock_subscription_admin.expect :streaming_pull, [].to_enum, [Enumerator, Hash]
       mock_subscription_admin.expect :streaming_pull, [].to_enum, [Enumerator, Hash]
-      mock_subscription_admin.expect :modify_ack_deadline, nil, [Hash]
+      mock_subscription_admin.expect :modify_ack_deadline_internal, nil, [Hash]
     end
   end
 
   doctest.before "Google::Cloud::PubSub::ReceivedMessage#reject!" do
     mock_pubsub do |mock_topic_admin, mock_subscription_admin|
       mock_subscription_admin.expect :get_subscription, subscription_resp, subscription: subscription_path("my-topic-sub")
-      mock_subscription_admin.expect :pull, OpenStruct.new(received_messages: [Google::Cloud::PubSub::V1::ReceivedMessage.new(ack_id: "2", message: pubsub_message)]), [Hash]
+      mock_subscription_admin.expect :pull_internal, OpenStruct.new(received_messages: [Google::Cloud::PubSub::V1::ReceivedMessage.new(ack_id: "2", message: pubsub_message)]), [Hash]
       mock_subscription_admin.expect :streaming_pull, [OpenStruct.new(received_messages: [Google::Cloud::PubSub::V1::ReceivedMessage.new(ack_id: "2", message: pubsub_message)])].to_enum, [Enumerator, Hash]
       mock_subscription_admin.expect :streaming_pull, [].to_enum, [Enumerator, Hash]
       mock_subscription_admin.expect :streaming_pull, [].to_enum, [Enumerator, Hash]
@@ -190,16 +191,16 @@ def mock_pubsub
       mock_subscription_admin.expect :streaming_pull, [].to_enum, [Enumerator, Hash]
       mock_subscription_admin.expect :streaming_pull, [].to_enum, [Enumerator, Hash]
       mock_subscription_admin.expect :streaming_pull, [].to_enum, [Enumerator, Hash]
-      mock_subscription_admin.expect :acknowledge, nil, [Hash]
+      mock_subscription_admin.expect :acknowledge_internal, nil, [Hash]
     end
   end
 
   doctest.before "Google::Cloud::PubSub::Subscriber#wait_for_messages" do
     mock_pubsub do |mock_topic_admin, mock_subscription_admin|
       mock_subscription_admin.expect :get_subscription, subscription_resp("my-topic-sub"), subscription: subscription_path("my-topic-sub")
-      mock_subscription_admin.expect :pull, OpenStruct.new(received_messages: [Google::Cloud::PubSub::V1::ReceivedMessage.new(ack_id: "2", message: pubsub_message)]),
+      mock_subscription_admin.expect :pull_internal, OpenStruct.new(received_messages: [Google::Cloud::PubSub::V1::ReceivedMessage.new(ack_id: "2", message: pubsub_message)]),
                              subscription: subscription_path("my-topic-sub"), max_messages: 100, return_immediately: false
-      mock_subscription_admin.expect :acknowledge, nil, subscription: subscription_path("my-topic-sub"), ack_ids: ["2"]
+      mock_subscription_admin.expect :acknowledge_internal, nil, subscription: subscription_path("my-topic-sub"), ack_ids: ["2"]
     end
   end
 
@@ -213,27 +214,27 @@ def mock_pubsub
   doctest.before "Google::Cloud::PubSub::Subscriber#pull@The `immediate: false` option is now recommended to avoid adverse impacts on pull operations:" do
      mock_pubsub do |mock_topic_admin, mock_subscription_admin|
      mock_subscription_admin.expect :get_subscription, subscription_resp("my-topic-sub"), subscription: subscription_path("my-topic-sub")
-     mock_subscription_admin.expect :pull, OpenStruct.new(received_messages: [Google::Cloud::PubSub::V1::ReceivedMessage.new(ack_id: "2", message: pubsub_message)]),
+     mock_subscription_admin.expect :pull_internal, OpenStruct.new(received_messages: [Google::Cloud::PubSub::V1::ReceivedMessage.new(ack_id: "2", message: pubsub_message)]),
                              subscription: subscription_path("my-topic-sub"), max_messages: 100, return_immediately: false
-     mock_subscription_admin.expect :acknowledge, nil, subscription: subscription_path("my-topic-sub"), ack_ids: ["2"]
+     mock_subscription_admin.expect :acknowledge_internal, nil, subscription: subscription_path("my-topic-sub"), ack_ids: ["2"]
     end
   end
 
   doctest.before "Google::Cloud::PubSub::Subscriber#pull@A maximum number of messages returned can also be specified:" do
     mock_pubsub do |mock_topic_admin, mock_subscription_admin|
       mock_subscription_admin.expect :get_subscription, subscription_resp("my-topic-sub"), subscription: subscription_path("my-topic-sub")
-      mock_subscription_admin.expect :pull, OpenStruct.new(received_messages: [Google::Cloud::PubSub::V1::ReceivedMessage.new(ack_id: "2", message: pubsub_message)]),
+      mock_subscription_admin.expect :pull_internal, OpenStruct.new(received_messages: [Google::Cloud::PubSub::V1::ReceivedMessage.new(ack_id: "2", message: pubsub_message)]),
                              subscription: subscription_path("my-topic-sub"), max_messages: 10, return_immediately: false
-      mock_subscription_admin.expect :acknowledge, nil, subscription: subscription_path("my-topic-sub"), ack_ids: ["2"]
+      mock_subscription_admin.expect :acknowledge_internal, nil, subscription: subscription_path("my-topic-sub"), ack_ids: ["2"]
     end
   end
 
   doctest.before "Google::Cloud::PubSub::Subscriber#modify_ack_deadline" do
     mock_pubsub do |mock_topic_admin, mock_subscription_admin|
       mock_subscription_admin.expect :get_subscription, subscription_resp, subscription: subscription_path("my-topic-sub")
-      mock_subscription_admin.expect :pull, OpenStruct.new(received_messages: [Google::Cloud::PubSub::V1::ReceivedMessage.new(ack_id: "2", message: pubsub_message)]),
+      mock_subscription_admin.expect :pull_internal, OpenStruct.new(received_messages: [Google::Cloud::PubSub::V1::ReceivedMessage.new(ack_id: "2", message: pubsub_message)]),
                              subscription: subscription_path("my-sub"), max_messages: 100, return_immediately: false
-      mock_subscription_admin.expect :modify_ack_deadline, nil, subscription: subscription_path("my-sub"), ack_ids: ["2"], ack_deadline_seconds: 120
+      mock_subscription_admin.expect :modify_ack_deadline_internal, nil, subscription: subscription_path("my-sub"), ack_ids: ["2"], ack_deadline_seconds: 120
 
 
     end
@@ -262,7 +263,7 @@ def mock_pubsub
       mock_subscription_admin.expect :streaming_pull, [].to_enum, [Enumerator, Hash]
       mock_subscription_admin.expect :streaming_pull, [].to_enum, [Enumerator, Hash]
       mock_subscription_admin.expect :streaming_pull, [].to_enum, [Enumerator, Hash]
-      mock_subscription_admin.expect :acknowledge, nil, ["projects/my-project/subscriptions/my-ordered-topic-sub", ["2"], Hash]
+      mock_subscription_admin.expect :acknowledge_internal, nil, ["projects/my-project/subscriptions/my-ordered-topic-sub", ["2"], Hash]
     end
   end
 
@@ -276,7 +277,7 @@ def mock_pubsub
       mock_subscription_admin.expect :streaming_pull, [].to_enum, [Enumerator, Hash]
       mock_subscription_admin.expect :streaming_pull, [].to_enum, [Enumerator, Hash]
       mock_subscription_admin.expect :streaming_pull, [].to_enum, [Enumerator, Hash]
-      mock_subscription_admin.expect :acknowledge, nil, [Hash]
+      mock_subscription_admin.expect :acknowledge_internal, nil, [Hash]
     end
   end
 
@@ -286,28 +287,34 @@ def mock_pubsub
   doctest.before "Google::Cloud::PubSub::Publisher" do
     mock_pubsub do |mock_topic_admin, mock_subscription_admin|
       mock_topic_admin.expect :get_topic, topic_resp, topic: topic_path("my-topic-only")
-      mock_topic_admin.expect :publish, OpenStruct.new(message_ids: ["1"]), [Hash]
+      mock_topic_admin.expect :publish_internal, OpenStruct.new(message_ids: ["1"]), [Hash]
+    end
+  end
+
+  doctest.before "Google::Cloud::PubSub::Publisher#reload!" do
+    mock_pubsub do |mock_topic_admin, mock_subscription_admin|
+      mock_topic_admin.expect :get_topic, topic_resp, topic: topic_path("my-topic")
     end
   end
 
   doctest.before "Google::Cloud::PubSub::Publisher#async_publisher" do
     mock_pubsub do |mock_topic_admin, mock_subscription_admin|
       mock_topic_admin.expect :get_topic, topic_resp, topic: topic_path("my-topic")
-      mock_topic_admin.expect :publish, OpenStruct.new(message_ids: ["1"]), [Hash]
+      mock_topic_admin.expect :publish_internal, OpenStruct.new(message_ids: ["1"]), [Hash]
     end
   end
 
   doctest.before "Google::Cloud::PubSub::Publisher#publish" do
     mock_pubsub do |mock_topic_admin, mock_subscription_admin|
       mock_topic_admin.expect :get_topic, topic_resp, topic: topic_path("my-topic")
-      mock_topic_admin.expect :publish, OpenStruct.new(message_ids: ["1"]), [Hash]
+      mock_topic_admin.expect :publish_internal, OpenStruct.new(message_ids: ["1"]), [Hash]
     end
   end
 
   doctest.before "Google::Cloud::PubSub::Publisher#publish@Additionally, a message can be published with attributes:" do
     mock_pubsub do |mock_topic_admin, mock_subscription_admin|
       mock_topic_admin.expect :get_topic, topic_resp, topic: topic_path("my-topic")
-      mock_topic_admin.expect :publish, OpenStruct.new(message_ids: ["1"]), [Hash]
+      mock_topic_admin.expect :publish_internal, OpenStruct.new(message_ids: ["1"]), [Hash]
     end
   end
 
@@ -319,14 +326,14 @@ def mock_pubsub
         pubsub_message("task 2 completed", { "foo" => "baz" }),
         pubsub_message("task 3 completed", { "foo" => "bif" })
       ]
-      mock_topic_admin.expect :publish, OpenStruct.new(message_ids: ["1", "2", "3"]), [Hash]
+      mock_topic_admin.expect :publish_internal, OpenStruct.new(message_ids: ["1", "2", "3"]), [Hash]
     end
   end
 
   doctest.before "Google::Cloud::PubSub::Publisher#publish@Ordered messages are supported using ordering_key:" do
     mock_pubsub do |mock_topic_admin, mock_subscription_admin|
       mock_topic_admin.expect :get_topic, topic_resp, topic: topic_path("my-ordered-topic")
-      mock_topic_admin.expect :publish, OpenStruct.new(message_ids: ["1"]), [Hash]
+      mock_topic_admin.expect :publish_internal, OpenStruct.new(message_ids: ["1"]), [Hash]
     end
   end
 
@@ -347,7 +354,7 @@ def mock_pubsub
         pubsub_message("task 2 completed", { "foo" => "baz" }),
         pubsub_message("task 3 completed", { "foo" => "bif" })
       ]
-      mock_topic_admin.expect :publish, OpenStruct.new(message_ids: ["1", "2", "3"]), [Hash]
+      mock_topic_admin.expect :publish_internal, OpenStruct.new(message_ids: ["1", "2", "3"]), [Hash]
     end
   end
 end
diff --git a/google-cloud-storage/support/doctest_helper.rb b/google-cloud-storage/support/doctest_helper.rb
index b81b7bf08db1..22816b1e3335 100644
--- a/google-cloud-storage/support/doctest_helper.rb
+++ b/google-cloud-storage/support/doctest_helper.rb
@@ -13,6 +13,8 @@
 # limitations under the License.
 
 require "minitest/focus"
+require "minitest/mock"
+require "ostruct"
 
 require "google/cloud/storage"
 require "google/cloud/pubsub"
diff --git a/google-cloud-trace/support/doctest_helper.rb b/google-cloud-trace/support/doctest_helper.rb
index 30a2a2fe26d4..4e4321b55cc1 100644
--- a/google-cloud-trace/support/doctest_helper.rb
+++ b/google-cloud-trace/support/doctest_helper.rb
@@ -16,6 +16,8 @@
 require "google/cloud/trace"
 require "minitest/rg"
 require "minitest/focus"
+require "minitest/mock"
+require "ostruct"
 require "active_record"
 
 module Google
diff --git a/google-cloud-translate-v2/support/doctest_helper.rb b/google-cloud-translate-v2/support/doctest_helper.rb
index 89f3984930e9..891599b59878 100644
--- a/google-cloud-translate-v2/support/doctest_helper.rb
+++ b/google-cloud-translate-v2/support/doctest_helper.rb
@@ -14,6 +14,8 @@
 
 require "google/cloud/translate/v2"
 require "minitest/focus"
+require "minitest/mock"
+require "ostruct"
 
 module Google
   module Cloud
@@ -55,7 +57,7 @@ def mock_translate
   doctest.before "Google::Cloud::Translate::V2.new" do
     mock_translate do |mock|
       res_attrs = { detectedSourceLanguage: "en", translatedText: "Salve mundi!" }
-      mock.expect :translate, list_translations_response([res_attrs]), [["Hello world!"], to: "la", from: nil, format: nil, model: nil, cid: nil]
+      mock.expect :translate, list_translations_response([res_attrs]), [["Hello world!"]], to: "la", from: nil, format: nil, model: nil, cid: nil
     end
   end
 
@@ -64,7 +66,7 @@ def mock_translate
   doctest.before "Google::Cloud::Translate::V2::Api" do
     mock_translate do |mock|
       res_attrs = { detectedSourceLanguage: "en", translatedText: "Salve mundi!" }
-      mock.expect :translate, list_translations_response([res_attrs]), [["Hello world!"], to: "la", from: nil, format: nil, model: nil, cid: nil]
+      mock.expect :translate, list_translations_response([res_attrs]), [["Hello world!"]], to: "la", from: nil, format: nil, model: nil, cid: nil
     end
   end
 
@@ -82,21 +84,21 @@ def mock_translate
   doctest.before "Google::Cloud::Translate::V2::Api#translate" do
     mock_translate do |mock|
       res_attrs = { detectedSourceLanguage: "en", translatedText: "Salve mundi!", model: "base" }
-      mock.expect :translate, list_translations_response([res_attrs]), [["Hello world!"], to: "la", from: nil, format: nil, model: nil, cid: nil]
+      mock.expect :translate, list_translations_response([res_attrs]), [["Hello world!"]], to: "la", from: nil, format: nil, model: nil, cid: nil
     end
   end
 
   doctest.before "Google::Cloud::Translate::V2::Api#translate@Using the neural machine translation model:" do
     mock_translate do |mock|
       res_attrs = { detectedSourceLanguage: "en", translatedText: "Salve mundi!", model: "nmt" }
-      mock.expect :translate, list_translations_response([res_attrs]), [["Hello world!"], to: "la", from: nil, format: nil, model: "nmt", cid: nil]
+      mock.expect :translate, list_translations_response([res_attrs]), [["Hello world!"]], to: "la", from: nil, format: nil, model: "nmt", cid: nil
     end
   end
 
   doctest.before "Google::Cloud::Translate::V2::Api#translate@Setting the `from` language." do
     mock_translate do |mock|
       res_attrs = { detectedSourceLanguage: nil, translatedText: "Salve mundi!" }
-      mock.expect :translate, list_translations_response([res_attrs]), [["Hello world!"], to: "la", from: "en", format: nil, model: nil, cid: nil]
+      mock.expect :translate, list_translations_response([res_attrs]), [["Hello world!"]], to: "la", from: "en", format: nil, model: nil, cid: nil
     end
   end
 
@@ -104,14 +106,14 @@ def mock_translate
     mock_translate do |mock|
       res_attrs_1 = { detectedSourceLanguage: nil, translatedText: "Salve amice." }
       res_attrs_2 = { detectedSourceLanguage: nil, translatedText: "Vide te mox." }
-      mock.expect :translate, list_translations_response([res_attrs_1, res_attrs_2]), [["Hello my friend.", "See you soon."], to: "la", from: "en", format: nil, model: nil, cid: nil]
+      mock.expect :translate, list_translations_response([res_attrs_1, res_attrs_2]), [["Hello my friend.", "See you soon."]], to: "la", from: "en", format: nil, model: nil, cid: nil
     end
   end
 
   doctest.before "Google::Cloud::Translate::V2::Api#translate@Preserving HTML tags." do
     mock_translate do |mock|
       res_attrs = { detectedSourceLanguage: nil, translatedText: "<strong>Salve</strong> mundi!" }
-      mock.expect :translate, list_translations_response([res_attrs]), [["<strong>Hello</strong> world!"], to: "la", from: nil, format: nil, model: nil, cid: nil]
+      mock.expect :translate, list_translations_response([res_attrs]), [["<strong>Hello</strong> world!"]], to: "la", from: nil, format: nil, model: nil, cid: nil
     end
   end
 
@@ -162,7 +164,7 @@ def mock_translate
   doctest.before "Google::Cloud::Translate::V2::Translation" do
     mock_translate do |mock|
       res_attrs = { detectedSourceLanguage: "en", translatedText: "Salve mundi!" }
-      mock.expect :translate, list_translations_response([res_attrs]), [["Hello world!"], to: "la", from: nil, format: nil, model: nil, cid: nil]
+      mock.expect :translate, list_translations_response([res_attrs]), [["Hello world!"]], to: "la", from: nil, format: nil, model: nil, cid: nil
     end
   end
 end