Do not use nested namespaces in torchaudio/sox (#2663)

Summary:
As it is a C++17 feature, and PyTorch and its extensions must still be C++14 compatible, as also specified in the top level CMakeLists.txt:
https://github.com/pytorch/audio/blob/8a0d7b36f7821fe55175f0d4e3ca6299b3817a6c/CMakeLists.txt#L30

Otherwise, it pollutes build logs with noisy
```
/Users/runner/work/test-infra/test-infra/pytorch/audio/torchaudio/csrc/sox/pybind/io.cpp:12:21: warning: nested namespace definition is a C++17 extension; define each namespace separately [-Wc++17-extensions]
namespace torchaudio::sox_io {
                    ^~~~~~~~
                     { namespace sox_io
```

Pull Request resolved: https://github.com/pytorch/audio/pull/2663

Reviewed By: atalman, nateanl

Differential Revision: D39362842

Pulled By: malfet

fbshipit-source-id: f9659d4420f1cc0194990d531455cf59b66c26b9

.clang-tidy

@@ -24,6 +24,7 @@ cppcoreguidelines-*,
 hicpp-exception-baseclass,
 hicpp-avoid-goto,
 modernize-*,
+-modernize-concat-nested-namespaces,
 -modernize-return-braced-init-list,
 -modernize-use-auto,
 -modernize-use-default-member-init,

torchaudio/csrc/sox/effects.cpp

@@ -5,7 +5,8 @@
 
 using namespace torchaudio::sox_utils;
 
-namespace torchaudio::sox_effects {
+namespace torchaudio {
+namespace sox_effects {
 
 namespace {
 
@@ -152,4 +153,5 @@ TORCH_LIBRARY_FRAGMENT(torchaudio, m) {
       &torchaudio::sox_effects::apply_effects_file);
 }
 
-} // namespace torchaudio::sox_effects
+} // namespace sox_effects
+} // namespace torchaudio

torchaudio/csrc/sox/effects.h

@@ -4,7 +4,8 @@
 #include <torch/script.h>
 #include <torchaudio/csrc/sox/utils.h>
 
-namespace torchaudio::sox_effects {
+namespace torchaudio {
+namespace sox_effects {
 
 void initialize_sox_effects();
 
@@ -24,6 +25,7 @@ auto apply_effects_file(
     const c10::optional<std::string>& format)
     -> c10::optional<std::tuple<torch::Tensor, int64_t>>;
 
-} // namespace torchaudio::sox_effects
+} // namespace sox_effects
+} // namespace torchaudio
 
 #endif

torchaudio/csrc/sox/pybind/effects.cpp

@@ -4,7 +4,8 @@
 
 using namespace torchaudio::sox_utils;
 
-namespace torchaudio::sox_effects {
+namespace torchaudio {
+namespace sox_effects {
 
 // Streaming decoding over file-like object is tricky because libsox operates on
 // FILE pointer. The folloing is what `sox` and `play` commands do
@@ -118,4 +119,5 @@ auto apply_effects_fileobj(
       tensor, static_cast<int64_t>(chain.getOutputSampleRate()));
 }
 
-} // namespace torchaudio::sox_effects
+} // namespace sox_effects
+} // namespace torchaudio

torchaudio/csrc/sox/pybind/effects.h

@@ -3,7 +3,8 @@
 
 #include <torch/extension.h>
 
-namespace torchaudio::sox_effects {
+namespace torchaudio {
+namespace sox_effects {
 
 auto apply_effects_fileobj(
     py::object fileobj,
@@ -13,6 +14,7 @@ auto apply_effects_fileobj(
     c10::optional<std::string> format)
     -> c10::optional<std::tuple<torch::Tensor, int64_t>>;
 
-} // namespace torchaudio::sox_effects
+} // namespace sox_effects
+} // namespace torchaudio
 
 #endif

torchaudio/csrc/sox/pybind/effects_chain.cpp

@@ -4,7 +4,8 @@
 
 using namespace torchaudio::sox_utils;
 
-namespace torchaudio::sox_effects_chain {
+namespace torchaudio {
+namespace sox_effects_chain {
 
 namespace {
 
@@ -232,4 +233,5 @@ void SoxEffectsChainPyBind::addOutputFileObj(
   }
 }
 
-} // namespace torchaudio::sox_effects_chain
+} // namespace sox_effects_chain
+} // namespace torchaudio

torchaudio/csrc/sox/pybind/effects_chain.h

@@ -4,7 +4,8 @@
 #include <torch/extension.h>
 #include <torchaudio/csrc/sox/effects_chain.h>
 
-namespace torchaudio::sox_effects_chain {
+namespace torchaudio {
+namespace sox_effects_chain {
 
 class SoxEffectsChainPyBind : public SoxEffectsChain {
   using SoxEffectsChain::SoxEffectsChain;
@@ -23,6 +24,7 @@ class SoxEffectsChainPyBind : public SoxEffectsChain {
       py::object* fileobj);
 };
 
-} // namespace torchaudio::sox_effects_chain
+} // namespace sox_effects_chain
+} // namespace torchaudio
 
 #endif

torchaudio/csrc/sox/pybind/io.cpp

@@ -9,7 +9,8 @@
 
 using namespace torchaudio::sox_utils;
 
-namespace torchaudio::sox_io {
+namespace torchaudio {
+namespace sox_io {
 
 auto get_info_fileobj(py::object fileobj, c10::optional<std::string> format)
     -> c10::optional<MetaDataTuple> {
@@ -190,4 +191,5 @@ void save_audio_fileobj(
   fileobj.attr("write")(py::bytes(buffer.ptr, buffer.size));
 }
 
-} // namespace torchaudio::sox_io
+} // namespace sox_io
+} // namespace torchaudio

torchaudio/csrc/sox/pybind/io.h

@@ -3,7 +3,8 @@
 
 #include <torch/extension.h>
 
-namespace torchaudio::sox_io {
+namespace torchaudio {
+namespace sox_io {
 
 using MetaDataTuple =
     std::tuple<int64_t, int64_t, int64_t, int64_t, std::string>;
@@ -30,6 +31,7 @@ void save_audio_fileobj(
     c10::optional<std::string> encoding,
     c10::optional<int64_t> bits_per_sample);
 
-} // namespace torchaudio::sox_io
+} // namespace sox_io
+} // namespace torchaudio
 
 #endif

torchaudio/csrc/sox/pybind/utils.cpp

 #include <torchaudio/csrc/sox/pybind/utils.h>
 
-namespace torchaudio::sox_utils {
+namespace torchaudio {
+namespace sox_utils {
 
 auto read_fileobj(py::object* fileobj, const uint64_t size, char* buffer)
     -> uint64_t {
@@ -28,4 +29,5 @@ auto read_fileobj(py::object* fileobj, const uint64_t size, char* buffer)
   return num_read;
 }
 
-} // namespace torchaudio::sox_utils
+} // namespace sox_utils
+} // namespace torchaudio

torchaudio/csrc/sox/pybind/utils.h

@@ -3,10 +3,12 @@
 
 #include <torch/extension.h>
 
-namespace torchaudio::sox_utils {
+namespace torchaudio {
+namespace sox_utils {
 
 auto read_fileobj(py::object* fileobj, uint64_t size, char* buffer) -> uint64_t;
 
-} // namespace torchaudio::sox_utils
+} // namespace sox_utils
+} // namespace torchaudio
 
 #endif