Apply clang-tidy modernize-concat-nested-namespaces

Summary: Apply [modernize-concat-nested-namespaces](https://clang.llvm.org/extra/clang-tidy/checks/modernize/concat-nested-namespaces.html)(C++17) check to `thrift/lib/cpp2`.

Reviewed By: thedavekwon

Differential Revision: D63978465

fbshipit-source-id: 5b0a68242d894eaa0349ed1308833037aeccc87e

Author: yoney

third-party/thrift/src/thrift/lib/cpp2/Adapt.h

@@ -25,9 +25,7 @@
 #include <thrift/lib/cpp/Field.h>
 #include <thrift/lib/cpp2/Thrift.h>
 
-namespace apache {
-namespace thrift {
-namespace adapt_detail {
+namespace apache::thrift::adapt_detail {
 
 // Identical to std::declval<const T&>.
 template <typename T>
@@ -526,6 +524,4 @@ uint32_t serializedSize(Protocol& prot, const AdaptedT& val, FallbackF f) {
       FallbackF>()(prot, val, f);
 }
 
-} // namespace adapt_detail
-} // namespace thrift
-} // namespace apache
+} // namespace apache::thrift::adapt_detail

third-party/thrift/src/thrift/lib/cpp2/Adapter.h

@@ -20,8 +20,7 @@
 #include <thrift/lib/cpp2/Thrift.h>
 #include <thrift/lib/cpp2/op/Clear.h>
 
-namespace apache {
-namespace thrift {
+namespace apache::thrift {
 namespace adapt_detail {
 
 // Used to detect if an adapted type has a reset method.
@@ -121,5 +120,4 @@ struct InlineAdapter {
   }
 };
 
-} // namespace thrift
-} // namespace apache
+} // namespace apache::thrift

third-party/thrift/src/thrift/lib/cpp2/BoxedValuePtr.h

@@ -31,9 +31,7 @@
 #define THRIFT_CONSTEXPR_IF_NOT_MSVC constexpr
 #endif
 
-namespace apache {
-namespace thrift {
-namespace detail {
+namespace apache::thrift::detail {
 
 // boxed_value_ptr will soon be replaced with boxed_value (defined below).
 template <typename T>
@@ -386,8 +384,6 @@ class boxed_value : public boost::totally_ordered<boxed_value<T>>,
   boxed_ptr<T> ptr_;
 };
 
-} // namespace detail
-} // namespace thrift
-} // namespace apache
+} // namespace apache::thrift::detail
 
 #undef THRIFT_CONSTEXPR_IF_NOT_MSVC

third-party/thrift/src/thrift/lib/cpp2/CloneableIOBuf.h

@@ -22,8 +22,7 @@
 #include <folly/io/IOBuf.h>
 #include <thrift/lib/cpp/Thrift.h>
 
-namespace apache {
-namespace thrift {
+namespace apache::thrift {
 
 namespace detail {
 
@@ -85,7 +84,6 @@ void swap(
 
 typedef apache::thrift::detail::CloneableUniquePtr<folly::IOBuf> CloneableIOBuf;
 
-} // namespace thrift
-} // namespace apache
+} // namespace apache::thrift
 
 #endif // #ifndef THRIFT_CLONEABLE_IOBUF_H_

third-party/thrift/src/thrift/lib/cpp2/FieldRef.h

@@ -32,8 +32,7 @@
 #include <thrift/lib/cpp2/FieldRefTraits.h>
 #include <thrift/lib/cpp2/Thrift.h>
 
-namespace apache {
-namespace thrift {
+namespace apache::thrift {
 namespace detail {
 
 template <typename T>
@@ -2505,5 +2504,4 @@ bool operator>=(const T& lhs, terse_field_ref<U> rhs) {
   return lhs >= *rhs;
 }
 
-} // namespace thrift
-} // namespace apache
+} // namespace apache::thrift

third-party/thrift/src/thrift/lib/cpp2/FieldRefHash.h

@@ -22,13 +22,9 @@
 #include <folly/Traits.h>
 #include <thrift/lib/cpp2/FieldRef.h>
 
-namespace apache {
-namespace thrift {
-namespace detail {
+namespace apache::thrift::detail {
 const size_t kHashValueForNonExistsOptionalField = -3333;
-} // namespace detail
-} // namespace thrift
-} // namespace apache
+} // namespace apache::thrift::detail
 
 namespace folly {
 template <class T>

third-party/thrift/src/thrift/lib/cpp2/FieldRefTraits.h

@@ -18,8 +18,8 @@
 
 #include <memory>
 #include <folly/Traits.h>
-namespace apache {
-namespace thrift {
+
+namespace apache::thrift {
 
 template <class T>
 class field_ref;
@@ -92,5 +92,4 @@ inline constexpr bool is_optional_or_union_field_ref_v =
     is_union_field_ref_v<T>;
 
 } // namespace detail
-} // namespace thrift
-} // namespace apache
+} // namespace apache::thrift

third-party/thrift/src/thrift/lib/cpp2/Flags.cpp

@@ -79,8 +79,7 @@ FlagsRegistry* getFlagsRegistry() {
 }
 } // namespace
 
-namespace apache {
-namespace thrift {
+namespace apache::thrift {
 namespace detail {
 namespace {
 
@@ -152,5 +151,4 @@ std::vector<ThriftFlagInfo> getAllThriftFlags() {
   return getFlagsRegistry()->getAllThriftFlags();
 }
 
-} // namespace thrift
-} // namespace apache
+} // namespace apache::thrift

third-party/thrift/src/thrift/lib/cpp2/Flags.h

@@ -30,8 +30,7 @@
 
 #include <thrift/lib/cpp2/PluggableFunction.h>
 
-namespace apache {
-namespace thrift {
+namespace apache::thrift {
 namespace detail {
 
 class FlagsBackend {
@@ -200,5 +199,4 @@ struct ThriftFlagInfo {
 };
 
 std::vector<ThriftFlagInfo> getAllThriftFlags();
-} // namespace thrift
-} // namespace apache
+} // namespace apache::thrift

third-party/thrift/src/thrift/lib/cpp2/GeneratedCodeHelper.cpp

@@ -35,8 +35,7 @@ using namespace std;
 using namespace folly;
 using namespace apache::thrift::transport;
 
-namespace apache {
-namespace thrift {
+namespace apache::thrift {
 
 namespace detail {
 
@@ -48,8 +47,7 @@ THRIFT_PLUGGABLE_FUNC_REGISTER(
 
 } // namespace detail
 
-namespace detail {
-namespace ac {
+namespace detail::ac {
 
 [[noreturn]] void throw_app_exn(const char* const msg) {
   throw TApplicationException(msg);
@@ -86,11 +84,9 @@ folly::exception_wrapper try_extract_any_exception(
   return {};
 }
 
-} // namespace ac
-} // namespace detail
+} // namespace detail::ac
 
-namespace detail {
-namespace ap {
+namespace detail::ap {
 
 template <typename ProtocolReader, typename ProtocolWriter>
 std::unique_ptr<folly::IOBuf> helper<ProtocolReader, ProtocolWriter>::write_exn(
@@ -243,11 +239,9 @@ MessageBegin deserializeMessageBegin(
   }
   return msgBegin;
 }
-} // namespace ap
-} // namespace detail
+} // namespace detail::ap
 
-namespace detail {
-namespace si {
+namespace detail::si {
 namespace {
 TrustedServerException createUnimplementedMethodException(
     std::string_view methodName) {
@@ -264,8 +258,7 @@ folly::exception_wrapper create_app_exn_unimplemented(const char* name) {
 [[noreturn]] void throw_app_exn_unimplemented(const char* const name) {
   throw createUnimplementedMethodException(name);
 }
-} // namespace si
-} // namespace detail
+} // namespace detail::si
 
 namespace {
 
@@ -354,5 +347,4 @@ bool includeInRecentRequestsCount(const std::string_view methodName) {
 
 } // namespace util
 
-} // namespace thrift
-} // namespace apache
+} // namespace apache::thrift