Adopt ruby_package in ruby generated code. (#4627)

* Adopt ruby_package in ruby generated code.

* Add test for ruby_package

.gitignore

@@ -174,6 +174,7 @@ js/testproto_libs2.js
 ruby/lib/
 ruby/tests/generated_code_pb.rb
 ruby/tests/test_import_pb.rb
+ruby/tests/test_ruby_package_pb.rb
 ruby/Gemfile.lock
 ruby/compatibility_tests/v3.0.0/protoc
 ruby/compatibility_tests/v3.0.0/tests/generated_code_pb.rb

ruby/Rakefile

@@ -87,6 +87,7 @@ end
 # Proto for tests.
 genproto_output << "tests/generated_code.rb"
 genproto_output << "tests/test_import.rb"
+genproto_output << "tests/test_ruby_package.rb"
 file "tests/generated_code.rb" => "tests/generated_code.proto" do |file_task|
   sh "../src/protoc --ruby_out=. tests/generated_code.proto"
 end
@@ -95,6 +96,10 @@ file "tests/test_import.rb" => "tests/test_import.proto" do |file_task|
   sh "../src/protoc --ruby_out=. tests/test_import.proto"
 end
 
+file "tests/test_ruby_package.rb" => "tests/test_ruby_package.proto" do |file_task|
+  sh "../src/protoc --ruby_out=. tests/test_ruby_package.proto"
+end
+
 task :genproto => genproto_output
 
 task :clean do

ruby/tests/generated_code_test.rb

@@ -5,6 +5,7 @@ $LOAD_PATH.unshift(File.expand_path(File.dirname(__FILE__)))
 
 require 'generated_code_pb'
 require 'test_import_pb'
+require 'test_ruby_package_pb'
 require 'test/unit'
 
 class GeneratedCodeTest < Test::Unit::TestCase
@@ -15,5 +16,6 @@ class GeneratedCodeTest < Test::Unit::TestCase
     # aspect of the extension (basic.rb is for that).
     m = A::B::C::TestMessage.new()
     m2 = FooBar::TestImportedMessage.new()
+    m3 = A::B::TestRubyPackageMessage.new()
   end
 end

ruby/tests/test_ruby_package.proto

@@ -0,0 +1,7 @@
+syntax = "proto3";
+
+package foo_bar;
+
+option ruby_package = "A.B";
+
+message TestRubyPackageMessage {}

src/google/protobuf/compiler/ruby/ruby_generator.cc

@@ -337,9 +337,20 @@ void GenerateEnumAssignment(
 }
 
 int GeneratePackageModules(
-    std::string package_name,
+    const FileDescriptor* file,
     google::protobuf::io::Printer* printer) {
   int levels = 0;
+  bool need_change_to_module;
+  std::string package_name;
+
+  if (file->options().has_ruby_package()) {
+    package_name = file->options().ruby_package();
+    need_change_to_module = false;
+  } else {
+    package_name = file->package();
+    need_change_to_module = true;
+  }
+
   while (!package_name.empty()) {
     size_t dot_index = package_name.find(".");
     string component;
@@ -350,7 +361,9 @@ int GeneratePackageModules(
       component = package_name.substr(0, dot_index);
       package_name = package_name.substr(dot_index + 1);
     }
-    component = PackageToModule(component);
+    if (need_change_to_module) {
+      component = PackageToModule(component);
+    }
     printer->Print(
       "module $name$\n",
       "name", component);
@@ -462,7 +475,7 @@ bool GenerateFile(const FileDescriptor* file, io::Printer* printer,
   printer->Print(
     "end\n\n");
 
-  int levels = GeneratePackageModules(file->package(), printer);
+  int levels = GeneratePackageModules(file, printer);
   for (int i = 0; i < file->message_type_count(); i++) {
     GenerateMessageAssignment("", file->message_type(i), printer);
   }