Introduce mojo interface for collecting StackSamplingProfiler data

components/metrics/public/cpp/call_stack_profile_struct_traits_unittest.cc

Index: components/metrics/public/cpp/call_stack_profile_struct_traits_unittest.cc
diff --git a/components/metrics/public/cpp/call_stack_profile_struct_traits_unittest.cc b/components/metrics/public/cpp/call_stack_profile_struct_traits_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..9029ef6278235b26da4de12b3658bc9a89135241
--- /dev/null
+++ b/components/metrics/public/cpp/call_stack_profile_struct_traits_unittest.cc
@@ -0,0 +1,204 @@
+// 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 <utility>
+
+#include "base/logging.h"
+#include "base/macros.h"
+#include "base/message_loop/message_loop.h"
+#include "components/metrics/public/interfaces/call_stack_profile_collector_test.mojom.h"
+#include "mojo/public/cpp/bindings/binding.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace metrics {
+
+namespace {
+
+base::StackSamplingProfiler::CallStackProfile CreateProfile(
+    const std::vector<base::StackSamplingProfiler::Module>& modules,
+    const std::vector<base::StackSamplingProfiler::Sample>& samples,
+    base::TimeDelta profile_duration,
+    base::TimeDelta sampling_period) {
+  base::StackSamplingProfiler::CallStackProfile profile;
+  profile.modules = modules;
+  profile.samples = samples;
+  profile.profile_duration = profile_duration;
+  profile.sampling_period = sampling_period;
+  return profile;
+}
+
+}
+
+class CallStackProfileCollectorTestImpl
+    : public mojom::CallStackProfileCollectorTest {
+ public:
+  explicit CallStackProfileCollectorTestImpl(
+      mojo::InterfaceRequest<mojom::CallStackProfileCollectorTest> request)
+      : binding_(this, std::move(request)) {
+  }
+
+  // CallStackProfileCollectorTest:
+  void BounceFrame(const base::StackSamplingProfiler::Frame& in,
+                   const BounceFrameCallback& callback) override {
+    callback.Run(in);
+  }
+
+  void BounceModule(const base::StackSamplingProfiler::Module& in,
+                    const BounceModuleCallback& callback) override {
+    callback.Run(in);
+  }
+
+  void BounceProfile(const base::StackSamplingProfiler::CallStackProfile& in,
+                     const BounceProfileCallback& callback) override {
+    callback.Run(in);
+  }
+
+ private:
+  mojo::Binding<CallStackProfileCollectorTest> binding_;
+};
+
+// Checks serialization/deserialization of Module fields.
+TEST(CallStackProfileStructTraitsTest, Module) {
+  using Module = base::StackSamplingProfiler::Module;
+
+  base::MessageLoop message_loop;

[Ilya Sherman, 2016/08/18 07:59:18]

nit: Why not declare this as part of the harness?

[Mike Wittman, 2016/08/18 17:49:19]

Done.

+
+  mojom::CallStackProfileCollectorTestPtr proxy;
+  CallStackProfileCollectorTestImpl impl(GetProxy(&proxy));
+
+  const Module serialize_cases[] = {
+    Module(0x0, "abcd", base::FilePath(base::FilePath::kCurrentDirectory)),
+    Module(0x10, "abcd", base::FilePath(base::FilePath::kCurrentDirectory)),
+    Module(1ULL << (sizeof(uintptr_t) * 8) * 3 / 4, "abcd",
+           base::FilePath(base::FilePath::kCurrentDirectory)),
+    Module(0x10, "", base::FilePath(base::FilePath::kCurrentDirectory)),

[Ilya Sherman, 2016/08/18 07:59:18]

nit: It would be great to have a brief comment for each of the input cases,
documenting what it's intending to test.  (And ditto for similar constructs
elsewhere in this file.)

[Mike Wittman, 2016/08/18 17:49:19]

Done.

+  };
+
+  for (const Module& input : serialize_cases) {
+    Module output;
+    EXPECT_TRUE(proxy->BounceModule(input, &output));
+
+    EXPECT_EQ(input.base_address, output.base_address);
+    EXPECT_EQ(input.id, output.id);
+    EXPECT_EQ(input.filename, output.filename);
+  }
+}
+
+// Checks serialization/deserialization of Frame fields.
+TEST(CallStackProfileStructTraitsTest, Frame) {
+  using Frame = base::StackSamplingProfiler::Frame;
+
+  base::MessageLoop message_loop;
+
+  mojom::CallStackProfileCollectorTestPtr proxy;
+  CallStackProfileCollectorTestImpl impl(GetProxy(&proxy));
+
+  const Frame serialize_cases[] = {
+    Frame(0x0, 10),
+    Frame(0x10, 10),
+    Frame(1ULL << (sizeof(uintptr_t) * 8) * 3 / 4, 10),
+    Frame(0xabcd, 0),
+    Frame(0xabcd, 1),
+    Frame(0xabcd, 10),
+    Frame(0xabcd, Frame::kUnknownModuleIndex),
+  };
+
+  for (const Frame& input : serialize_cases) {
+    Frame output;
+    EXPECT_TRUE(proxy->BounceFrame(input, &output));
+
+    EXPECT_EQ(input.instruction_pointer, output.instruction_pointer);
+    EXPECT_EQ(input.module_index, output.module_index);
+  }
+}
+
+// Checks serialization/deserialization of Profile fields, including validation
+// of the Frame module_index field.
+TEST(CallStackProfileStructTraitsTest, Profile) {
+  using Module = base::StackSamplingProfiler::Module;
+  using Frame = base::StackSamplingProfiler::Frame;
+  using Sample = base::StackSamplingProfiler::Sample;
+  using Profile = base::StackSamplingProfiler::CallStackProfile;

[Ilya Sherman, 2016/08/18 07:59:18]

Hmm, why not write these using statements at the top of the file?

[Mike Wittman, 2016/08/18 17:49:19]

The code under test is translating between two sets of similarly-named types, so
I think it's better to keep the type aliases close to the use to avoid potential
confusion.

+
+  base::MessageLoop message_loop;
+
+  mojom::CallStackProfileCollectorTestPtr proxy;
+  CallStackProfileCollectorTestImpl impl(GetProxy(&proxy));
+
+  struct SerializeCase {
+    Profile profile;
+    bool expect_success;
+  };
+  const SerializeCase serialize_cases[] = {
+    {
+      CreateProfile(std::vector<Module>(), std::vector<Sample>(),
+                    base::TimeDelta::FromSeconds(1),
+                    base::TimeDelta::FromSeconds(2)),
+      true
+    },
+    {
+      CreateProfile({ Module(0x4000, "a", base::FilePath()) },
+                    std::vector<Sample>(),
+                    base::TimeDelta::FromSeconds(1),
+                    base::TimeDelta::FromSeconds(2)),
+      true
+    },
+    {
+      CreateProfile({
+                      Module(0x4000, "a", base::FilePath()),
+                      Module(0x4100, "b", base::FilePath()),
+                    },
+                    {
+                      {
+                        Frame(0x4010, 0),
+                        Frame(0x4110, 1),
+                        Frame(0x4110, Frame::kUnknownModuleIndex),
+                      }
+                    },
+                    base::TimeDelta::FromSeconds(1),
+                    base::TimeDelta::FromSeconds(2)),
+      true
+    },
+    // The out of range module index in the second sample should cause the
+    // entire deserialization to fail.
+    {
+      CreateProfile({
+                      Module(0x4000, "a", base::FilePath()),
+                      Module(0x4100, "b", base::FilePath()),
+                    },
+                    {
+                      {
+                        Frame(0x4010, 0),
+                        Frame(0x4110, 1),
+                        Frame(0x4110, Frame::kUnknownModuleIndex),
+                      },
+                      {
+                        Frame(0x4010, 0),
+                        Frame(0x4110, 2),
+                      },
+                    },
+                    base::TimeDelta::FromSeconds(1),
+                    base::TimeDelta::FromSeconds(2)),
+      false
+    },
+  };
+
+  for (const SerializeCase& input : serialize_cases) {
+    SCOPED_TRACE(&input - &serialize_cases[0]);
+
+    Profile output;
+    EXPECT_EQ(input.expect_success,
+              proxy->BounceProfile(input.profile, &output));
+
+    if (!input.expect_success)
+      continue;
+
+    EXPECT_EQ(input.profile.modules, output.modules);
+    EXPECT_EQ(input.profile.samples, output.samples);
+    EXPECT_EQ(input.profile.profile_duration, output.profile_duration);
+    EXPECT_EQ(input.profile.sampling_period, output.sampling_period);
+  }
+}
+
+}  // namespace metrics