pw_rpc: Add missing codegen test

This change adds the source file for the RPC codegen unit test, which
was accidentally excluded from the previous codegen CL.

Change-Id: Ia30cf82d7f3eafcdf518710457a092948b29355e
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/13681
Reviewed-by: Wyatt Hepler <hepler@google.com>
Commit-Queue: Alexei Frolov <frolv@google.com>
diff --git a/pw_rpc/BUILD b/pw_rpc/BUILD
index 36e8c8b..fccebc7 100644
--- a/pw_rpc/BUILD
+++ b/pw_rpc/BUILD
@@ -90,7 +90,7 @@
 filegroup(
     name = "nanopb",
     srcs = [
-        "nanopb/codegen_manual_test.cc",
+        "nanopb/codegen_test.cc",
         "nanopb/method.cc",
         "nanopb/method_test.cc",
         "nanopb/public_overrides/pw_rpc/internal/method.h",
diff --git a/pw_rpc/nanopb/codegen_test.cc b/pw_rpc/nanopb/codegen_test.cc
new file mode 100644
index 0000000..b2de196
--- /dev/null
+++ b/pw_rpc/nanopb/codegen_test.cc
@@ -0,0 +1,28 @@
+// Copyright 2020 The Pigweed Authors
+//
+// 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.
+
+#include "gtest/gtest.h"
+#include "pw_rpc_test_protos/test_rpc.pb.h"
+
+namespace pw::rpc::internal {
+namespace {
+
+TEST(NanopbCodegen, CompilesProperly) {
+  test::TestService service;
+  EXPECT_EQ(service.id(), 0x105b6ac8u);
+  EXPECT_STREQ(service.name(), "TestService");
+}
+
+}  // namespace
+}  // namespace pw::rpc::internal