Tracing V2: Proto fields reflection.

components/tracing/test/proto_zero_generation_unittest.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <limits>
 #include <memory>
 #include <vector>
 
 #include "components/tracing/core/proto_zero_message_handle.h"
 #include "components/tracing/test/example_proto/library.pbzero.h"
 #include "components/tracing/test/example_proto/test_messages.pb.h"
 #include "components/tracing/test/example_proto/test_messages.pbzero.h"
 #include "components/tracing/test/fake_scattered_buffer.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace tracing {
 namespace proto {
 
 namespace pbtest = pbzero::foo::bar;
 namespace pbgold = foo::bar;  // Official C++ protobuf compiler.
 
 using tracing::v2::FakeScatteredBuffer;
 using tracing::v2::ProtoZeroMessage;
 using tracing::v2::ScatteredStreamWriter;
 using tracing::v2::ProtoZeroMessageHandle;
 using tracing::v2::ProtoZeroMessageHandleBase;
+using tracing::v2::proto::ProtoFieldDescriptor;
 
 constexpr size_t kChunkSize = 42;
 
 class ProtoZeroConformanceTest : public ::testing::Test {
  public:
   void SetUp() override {
     buffer_.reset(new FakeScatteredBuffer(kChunkSize));
     stream_writer_.reset(new ScatteredStreamWriter(buffer_.get()));
   }
 
@@ skipping 111 matching lines @@
   EXPECT_FALSE(gold_msg_a.repeated_a(1).has_value_b());
   EXPECT_EQ(1000, gold_msg_a.super_nested().value_c());
 }
 
 TEST(ProtoZeroTest, Simple) {
   // Test the includes for indirect public import: library.pbzero.h ->
   // library_internals/galaxies.pbzero.h -> upper_import.pbzero.h .
   EXPECT_LE(0u, sizeof(pbtest::TrickyPublicImport));
 }
 
-TEST(ProtoZeroTest, FieldNumbers) {
+TEST(ProtoZeroTest, Reflection) {
   // Tests camel case conversion as well.
   EXPECT_EQ(1, pbtest::CamelCaseFields::kFooBarBazFieldNumber);
   EXPECT_EQ(2, pbtest::CamelCaseFields::kBarBazFieldNumber);
   EXPECT_EQ(3, pbtest::CamelCaseFields::kMooMooFieldNumber);
   EXPECT_EQ(4, pbtest::CamelCaseFields::kURLEncoderFieldNumber);
   EXPECT_EQ(5, pbtest::CamelCaseFields::kXMapFieldNumber);
   EXPECT_EQ(6, pbtest::CamelCaseFields::kUrLENcoDerFieldNumber);
   EXPECT_EQ(7, pbtest::CamelCaseFields::kBigBangFieldNumber);
   EXPECT_EQ(8, pbtest::CamelCaseFields::kU2FieldNumber);
   EXPECT_EQ(9, pbtest::CamelCaseFields::kBangBigFieldNumber);
+
+  const ProtoFieldDescriptor* reflection =
+       pbtest::EveryField::GetFieldDescriptor(
+           pbtest::EveryField::kFieldInt32FieldNumber);
+  EXPECT_STREQ("field_int32", reflection->name());
+  EXPECT_EQ(ProtoFieldDescriptor::Type::TYPE_INT32, reflection->type());
+  EXPECT_EQ(1u, reflection->number());
+  EXPECT_FALSE(reflection->is_repeated());
+  EXPECT_TRUE(reflection->is_valid());
+
+  EXPECT_FALSE(pbtest::TransgalacticParcel::GetFieldDescriptor(42)->is_valid());
 }
 
 }  // namespace proto
 }  // namespace tracing