Remove namespace_cpp2 and related machinery

Summary:
This diff removes the hacks in C++ (`get_namespace_array_deprecated`).

There is certainly more room for improvement, which will come in future diffs.

Reviewed By: iahs

Differential Revision: D67636660

fbshipit-source-id: 53ce12b130f5aec50d67038265a850ec5baabe9d

thrift/compiler/generate/t_mstch_cpp2_generator.cc

@@ -274,8 +274,8 @@ class t_mstch_cpp2_generator : public t_mstch_generator {
     opts.allowed_undefined_variables = {
         "program:autogen_path",
         "service:autogen_path",
-        "program:namespace_cpp2",
-        "service:namespace_cpp2",
+        "program:qualified_namespace",
+        "service:qualified_namespace",
         "field:fatal_annotations?",
         "value:enable_referencing?",
     };
@@ -297,7 +297,6 @@ class t_mstch_cpp2_generator : public t_mstch_generator {
   void fill_validator_visitors(ast_validator&) const override;
   static std::string get_cpp2_namespace(const t_program* program);
   static std::string get_cpp2_unprefixed_namespace(const t_program* program);
-  static mstch::array get_namespace_array(const t_program* program);
   static mstch::array cpp_includes(const t_program* program);
   static mstch::node include_prefix(
       const t_program* program, std::map<std::string, std::string>& options);
@@ -347,7 +346,6 @@ class cpp_mstch_program : public mstch_program {
         {{"program:cpp_includes", &cpp_mstch_program::cpp_includes},
          {"program:qualified_namespace",
           &cpp_mstch_program::qualified_namespace},
-         {"program:namespace_cpp2", &cpp_mstch_program::namespace_cpp2},
          {"program:include_prefix", &cpp_mstch_program::include_prefix},
          {"program:cpp_declare_hash?", &cpp_mstch_program::cpp_declare_hash},
          {"program:thrift_includes", &cpp_mstch_program::thrift_includes},
@@ -465,9 +463,6 @@ class cpp_mstch_program : public mstch_program {
   mstch::node qualified_namespace() {
     return t_mstch_cpp2_generator::get_cpp2_unprefixed_namespace(program_);
   }
-  mstch::node namespace_cpp2() {
-    return t_mstch_cpp2_generator::get_namespace_array(program_);
-  }
   mstch::node cpp_includes() {
     mstch::array includes = t_mstch_cpp2_generator::cpp_includes(program_);
     auto it = context_.options.find("includes");
@@ -815,7 +810,6 @@ class cpp_mstch_service : public mstch_service {
             {"service:thrift_includes", &cpp_mstch_service::thrift_includes},
             {"service:qualified_namespace",
              &cpp_mstch_service::qualified_namespace},
-            {"service:namespace_cpp2", &cpp_mstch_service::namespace_cpp2},
             {"service:oneway_functions", &cpp_mstch_service::oneway_functions},
             {"service:oneways?", &cpp_mstch_service::has_oneway},
             {"service:cpp_includes", &cpp_mstch_service::cpp_includes},
@@ -871,9 +865,6 @@ class cpp_mstch_service : public mstch_service {
     return t_mstch_cpp2_generator::get_cpp2_unprefixed_namespace(
         service_->program());
   }
-  mstch::node namespace_cpp2() {
-    return t_mstch_cpp2_generator::get_namespace_array(service_->program());
-  }
   mstch::node oneway_functions() {
     std::vector<const t_function*> oneway_functions;
     for (const auto* function : get_functions()) {
@@ -1099,7 +1090,7 @@ class cpp_mstch_type : public mstch_type {
             {"type:cpp_template", &cpp_mstch_type::cpp_template},
             {"type:cpp_indirection?", &cpp_mstch_type::cpp_indirection},
             {"type:non_empty_struct?", &cpp_mstch_type::is_non_empty_struct},
-            {"type:namespace_cpp2", &cpp_mstch_type::namespace_cpp2},
+            {"type:qualified_namespace", &cpp_mstch_type::qualified_namespace},
             {"type:cpp_declare_hash", &cpp_mstch_type::cpp_declare_hash},
             {"type:cpp_declare_equal_to",
              &cpp_mstch_type::cpp_declare_equal_to},
@@ -1215,8 +1206,9 @@ class cpp_mstch_type : public mstch_type {
     auto as_struct = dynamic_cast<const t_struct*>(resolved_type_);
     return as_struct && as_struct->has_fields();
   }
-  mstch::node namespace_cpp2() {
-    return t_mstch_cpp2_generator::get_namespace_array(type_->program());
+  mstch::node qualified_namespace() {
+    return t_mstch_cpp2_generator::get_cpp2_unprefixed_namespace(
+        type_->program());
   }
   mstch::node type_class() { return cpp2::get_gen_type_class(*resolved_type_); }
   mstch::node type_tag() {
@@ -2727,22 +2719,6 @@ std::string t_mstch_cpp2_generator::get_cpp2_namespace(
   return cpp2::get_gen_unprefixed_namespace(*program);
 }
 
-mstch::array t_mstch_cpp2_generator::get_namespace_array(
-    const t_program* program) {
-  const auto v = cpp2::get_gen_namespace_components(*program);
-  mstch::array a;
-  for (auto it = v.begin(); it != v.end(); ++it) {
-    mstch::map m;
-    m.emplace("namespace:name", *it);
-    a.push_back(m);
-  }
-  for (auto itr = a.begin(); itr != a.end(); ++itr) {
-    std::get<mstch::map>(*itr).emplace("first?", itr == a.begin());
-    std::get<mstch::map>(*itr).emplace("last?", std::next(itr) == a.end());
-  }
-  return a;
-}
-
 mstch::array t_mstch_cpp2_generator::cpp_includes(const t_program* program) {
   mstch::array a;
   if (program->language_includes().count("cpp")) {

thrift/compiler/generate/templates/cpp2/common/const_value.mustache

@@ -27,6 +27,6 @@ Base Constant Values
 }}{{#value:string?}}"{{value:string_value}}"{{/value:string?}}{{!
 
 }}{{#value:enum?}}{{!
-  }}{{#value:enum_value?}}{{> common/type_namespace_cpp2}}{{type:cpp_name}}::{{value:enum_value_cpp_name}}{{/value:enum_value?}}{{!
-  }}{{^value:enum_value?}}static_cast<{{> common/type_namespace_cpp2}}{{type:cpp_name}}>({{value:integer_value}}){{/value:enum_value?}}{{!
+  }}{{#value:enum_value?}} ::{{type:qualified_namespace}}::{{type:cpp_name}}::{{value:enum_value_cpp_name}}{{/value:enum_value?}}{{!
+  }}{{^value:enum_value?}}static_cast< ::{{type:qualified_namespace}}::{{type:cpp_name}}>({{value:integer_value}}){{/value:enum_value?}}{{!
 }}{{/value:enum?}}

thrift/compiler/generate/templates/cpp2/common/iterate_const_values.mustache

@@ -32,7 +32,7 @@ Reference other constants:
     }}{{#value:referenceable?}}{{!
       }}{{#value:owning_const}}{{!
         }}{{#constant:program}}{{!
-          }}{{#program:namespace_cpp2}}::{{namespace:name}}{{#last?}}::{{/last?}}{{/program:namespace_cpp2}}{{program:name}}_constants::{{constant:name}}(){{!
+          }}::{{program:qualified_namespace}}::{{program:name}}_constants::{{constant:name}}(){{!
         }}{{/constant:program}}{{!
       }}{{/value:owning_const}}{{!
     }}{{/value:referenceable?}}{{!

thrift/compiler/generate/templates/cpp2/common/namespace_cpp2.mustache

@@ -14,4 +14,14 @@
   See the License for the specific language governing permissions and
   limitations under the License.
 
-}}::{{#program:namespace_cpp2}}{{namespace:name}}{{^last?}}::{{/last?}}{{/program:namespace_cpp2}}{{> common/service_namespace_cpp2}}::
+}}
+{{#pragma single-line}}
+::
+{{#if program:qualified_namespace}}
+{{program:qualified_namespace}}
+{{/if program:qualified_namespace}}
+
+{{#if service:qualified_namespace}}
+{{service:qualified_namespace}}
+{{/if service:qualified_namespace}}
+::

thrift/compiler/generate/templates/cpp2/module_metadata.h.mustache

@@ -27,9 +27,9 @@
 {{/program:thrift_includes}}
 
 {{#program:services}}
-{{> common/service_namespace_cpp2_begin }}
+namespace {{service:qualified_namespace}} {
 class {{service:cpp_name}};
-{{> common/service_namespace_cpp2_end }}
+} // namespace {{service:qualified_namespace}}
 {{/program:services}}
 
 namespace apache {

thrift/compiler/generate/templates/cpp2/service_async_client_cpp/received_wrapped.mustache

@@ -36,7 +36,7 @@ folly::exception_wrapper {{> service_common/client_class_name}}::recv_wrapped_{{
   struct ExMapType {
     bool operator()(typename result::SinkPResultType& res, folly::exception_wrapper ew) {
       {{#function:sink_exceptions}}
-      if (ew.with_exception([&]({{#field:type}}{{> common/type_namespace_cpp2}}{{type:name}}{{/field:type}}& e) {
+      if (ew.with_exception([&]({{#field:type}} ::{{type:qualified_namespace}}::{{type:name}}{{/field:type}}& e) {
             res.get<{{field:index_plus_one}}>().ref() = e;
             res.setIsSet({{field:index_plus_one}}, true);
           })) {

thrift/compiler/generate/templates/cpp2/service_cpp/handlers_cpp.mustache

@@ -29,7 +29,7 @@ std::optional<apache::thrift::schema::DefinitionsSchema> {{> service_common/serv
 {{#program}}
 {{#program:has_schema?}}
   std::optional<apache::thrift::schema::DefinitionsSchema> ret = schema::DefinitionsSchema{};
-  ret->schema = ::apache::thrift::SchemaRegistry::mergeSchemas(::{{> common/service_namespace_cpp2}}::{{program:name}}_constants::{{program:schema_name}}_includes());
+  ret->schema = ::apache::thrift::SchemaRegistry::mergeSchemas(::{{service:qualified_namespace}}::{{program:name}}_constants::{{program:schema_name}}_includes());
   ret->definitions = {"{{service:definition_key}}"};
   return ret;
 {{/program:has_schema?}}

thrift/compiler/generate/templates/cpp2/service_tcc/process_and_return.mustache

@@ -231,7 +231,7 @@ std::pair<apache::thrift::SerializedResponse, apache::thrift::detail::SinkConsum
   struct ExMapType {
     bool operator()(StreamPResultType& res, folly::exception_wrapper ew) {
       {{#function:stream_exceptions}}
-      if (ew.with_exception([&]({{#field:type}}{{> common/type_namespace_cpp2}}{{type:name}}{{/field:type}}& e) {
+      if (ew.with_exception([&]({{#field:type}} ::{{type:qualified_namespace}}::{{type:name}}{{/field:type}}& e) {
             res.get<{{field:index_plus_one}}>().ref() = e;
             res.setIsSet({{field:index_plus_one}}, true);
           })) {
@@ -261,7 +261,7 @@ std::pair<apache::thrift::SerializedResponse, apache::thrift::detail::SinkConsum
   struct ExMapType {
     bool operator()(FinalResponsePResultType& res, folly::exception_wrapper ew) {
       {{#function:sink_final_response_exceptions}}
-      if (ew.with_exception([&]({{#field:type}}{{> common/type_namespace_cpp2}}{{type:name}}{{/field:type}}& e) {
+      if (ew.with_exception([&]({{#field:type}} ::{{type:qualified_namespace}}::{{type:name}}{{/field:type}}& e) {
             res.get<{{field:index_plus_one}}>().ref() = e;
             res.setIsSet({{field:index_plus_one}}, true);
           })) {
@@ -308,12 +308,12 @@ void {{service:parent_service_cpp_name}}AsyncProcessor::throw_wrapped_{{function
   {{> common/namespace_cpp2}}{{service:parent_service_cpp_name}}_{{function:prefixed_name}}_presult result;
 {{/function:exceptions?}}
 {{#function:exceptions}}
-  if (ew.with_exception([&]({{#field:type}}{{> common/type_namespace_cpp2}}{{type:name}}{{/field:type}}& e) {
+  if (ew.with_exception([&]({{#field:type}} ::{{type:qualified_namespace}}::{{type:name}}{{/field:type}}& e) {
     if (ctx) {
       ctx->userExceptionWrapped(true, ew);
     }
     ::apache::thrift::util::appendExceptionToHeader(ew, *reqCtx);
-    ::apache::thrift::util::appendErrorClassificationToHeader<{{#field:type}}{{> common/type_namespace_cpp2}}{{type:name}}{{/field:type}}>(ew, *reqCtx);
+    ::apache::thrift::util::appendErrorClassificationToHeader<{{#field:type}} ::{{type:qualified_namespace}}::{{type:name}}{{/field:type}}>(ew, *reqCtx);
 {{#function:cpp_void?}}
     result.get<{{field:index}}>().ref() = e;
     result.setIsSet({{field:index}}, true);

thrift/compiler/test/fixtures/adapter/out/cpp2/gen-cpp2/module_metadata.h

@@ -11,16 +11,12 @@
 #include <thrift/lib/cpp2/gen/module_metadata_h.h>
 #include "thrift/compiler/test/fixtures/adapter/gen-cpp2/module_types.h"
 
-namespace facebook {
-namespace thrift {
-namespace test {
+namespace facebook::thrift::test {
 class Service;
-}}} // namespace facebook::thrift::test
-namespace facebook {
-namespace thrift {
-namespace test {
+} // namespace facebook::thrift::test
+namespace facebook::thrift::test {
 class AdapterService;
-}}} // namespace facebook::thrift::test
+} // namespace facebook::thrift::test
 
 namespace apache {
 namespace thrift {

thrift/compiler/test/fixtures/basic-structured-annotations/out/cpp2/gen-cpp2/module_metadata.h

@@ -13,11 +13,9 @@
 #include "thrift/compiler/test/fixtures/basic-structured-annotations/gen-cpp2/included_metadata.h"
 #include "thrift/compiler/test/fixtures/basic-structured-annotations/gen-cpp2/namespaced_metadata.h"
 
-namespace test {
-namespace fixtures {
-namespace basic-structured-annotations {
+namespace test::fixtures::basic-structured-annotations {
 class MyService;
-}}} // namespace test::fixtures::basic-structured-annotations
+} // namespace test::fixtures::basic-structured-annotations
 
 namespace apache {
 namespace thrift {

thrift/compiler/test/fixtures/basic/out/cpp2/gen-cpp2/module_metadata.h

@@ -11,26 +11,18 @@
 #include <thrift/lib/cpp2/gen/module_metadata_h.h>
 #include "thrift/compiler/test/fixtures/basic/gen-cpp2/module_types.h"
 
-namespace test {
-namespace fixtures {
-namespace basic {
+namespace test::fixtures::basic {
 class FooService;
-}}} // namespace test::fixtures::basic
-namespace test {
-namespace fixtures {
-namespace basic {
+} // namespace test::fixtures::basic
+namespace test::fixtures::basic {
 class FB303Service;
-}}} // namespace test::fixtures::basic
-namespace test {
-namespace fixtures {
-namespace basic {
+} // namespace test::fixtures::basic
+namespace test::fixtures::basic {
 class MyService;
-}}} // namespace test::fixtures::basic
-namespace test {
-namespace fixtures {
-namespace basic {
+} // namespace test::fixtures::basic
+namespace test::fixtures::basic {
 class DbMixedStackArguments;
-}}} // namespace test::fixtures::basic
+} // namespace test::fixtures::basic
 
 namespace apache {
 namespace thrift {

thrift/compiler/test/fixtures/fatal/out/cpp2/gen-cpp2/module_metadata.h

@@ -13,22 +13,18 @@
 #include "thrift/compiler/test/fixtures/fatal/gen-cpp2/reflection_dep_B_metadata.h"
 #include "thrift/compiler/test/fixtures/fatal/gen-cpp2/reflection_dep_C_metadata.h"
 
-namespace test_cpp2 {
-namespace cpp_reflection {
+namespace test_cpp2::cpp_reflection {
 class service1;
-}} // namespace test_cpp2::cpp_reflection
-namespace test_cpp2 {
-namespace cpp_reflection {
+} // namespace test_cpp2::cpp_reflection
+namespace test_cpp2::cpp_reflection {
 class service2;
-}} // namespace test_cpp2::cpp_reflection
-namespace test_cpp2 {
-namespace cpp_reflection {
+} // namespace test_cpp2::cpp_reflection
+namespace test_cpp2::cpp_reflection {
 class service3;
-}} // namespace test_cpp2::cpp_reflection
-namespace test_cpp2 {
-namespace cpp_reflection {
+} // namespace test_cpp2::cpp_reflection
+namespace test_cpp2::cpp_reflection {
 class service_with_special_names;
-}} // namespace test_cpp2::cpp_reflection
+} // namespace test_cpp2::cpp_reflection
 
 namespace apache {
 namespace thrift {

thrift/compiler/test/fixtures/interactions/out/cpp2_shared/gen-cpp2/shared_metadata.h

@@ -11,10 +11,9 @@
 #include <thrift/lib/cpp2/gen/module_metadata_h.h>
 #include "thrift/compiler/test/fixtures/interactions/gen-cpp2/shared_types.h"
 
-namespace thrift {
-namespace shared_interactions {
+namespace thrift::shared_interactions {
 class InteractLocally;
-}} // namespace thrift::shared_interactions
+} // namespace thrift::shared_interactions
 
 namespace apache {
 namespace thrift {