Merge pull request #4816 from hrsht/hrsht/zanker-proto2

Basic Proto2 support for Ruby gem

.gitignore

@@ -171,9 +171,14 @@ js/testproto_libs2.js
 
 # ruby test output
 ruby/lib/
+ruby/tests/basic_test_pb.rb
+ruby/tests/basic_test_proto2_pb.rb
 ruby/tests/generated_code_pb.rb
 ruby/tests/test_import_pb.rb
 ruby/tests/test_ruby_package_pb.rb
+ruby/tests/generated_code_proto2_pb.rb
+ruby/tests/test_import_proto2_pb.rb
+ruby/tests/test_ruby_package_proto2_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

@@ -86,20 +86,45 @@ end
 
 # Proto for tests.
 genproto_output << "tests/generated_code.rb"
+genproto_output << "tests/generated_code_proto2.rb"
 genproto_output << "tests/test_import.rb"
+genproto_output << "tests/test_import_proto2.rb"
 genproto_output << "tests/test_ruby_package.rb"
+genproto_output << "tests/test_ruby_package_proto2.rb"
+genproto_output << "tests/basic_test.rb"
+genproto_output << "tests/basic_test_proto2.rb"
 file "tests/generated_code.rb" => "tests/generated_code.proto" do |file_task|
   sh "../src/protoc --ruby_out=. tests/generated_code.proto"
 end
 
+file "tests/generated_code_proto2.rb" => "tests/generated_code_proto2.proto" do |file_task|
+  sh "../src/protoc --ruby_out=. tests/generated_code_proto2.proto"
+end
+
 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_import_proto2.rb" => "tests/test_import_proto2.proto" do |file_task|
+  sh "../src/protoc --ruby_out=. tests/test_import_proto2.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
 
+file "tests/test_ruby_package_proto2.rb" => "tests/test_ruby_package_proto2.proto" do |file_task|
+  sh "../src/protoc --ruby_out=. tests/test_ruby_package_proto2.proto"
+end
+
+file "tests/basic_test.rb" => "tests/basic_test.proto" do |file_task|
+  sh "../src/protoc --ruby_out=. tests/basic_test.proto"
+end
+
+file "tests/basic_test_proto2.rb" => "tests/basic_test_proto2.proto" do |file_task|
+  sh "../src/protoc --ruby_out=. tests/basic_test_proto2.proto"
+end
+
 task :genproto => genproto_output
 
 task :clean do
@@ -110,7 +135,7 @@ Gem::PackageTask.new(spec) do |pkg|
 end
 
 Rake::TestTask.new(:test => :build) do |t|
-  t.test_files = FileList["tests/*.rb"].exclude("tests/gc_test.rb")
+  t.test_files = FileList["tests/*.rb"].exclude("tests/gc_test.rb", "tests/common_tests.rb")
 end
 
 # gc_test needs to be split out to ensure the generated file hasn't been

ruby/ext/google/protobuf_c/protobuf.c

@@ -91,12 +91,14 @@ void Init_protobuf_c() {
   descriptor_instancevar_interned = rb_intern(kDescriptorInstanceVar);
   DescriptorPool_register(protobuf);
   Descriptor_register(protobuf);
+  FileDescriptor_register(protobuf);
   FieldDescriptor_register(protobuf);
   OneofDescriptor_register(protobuf);
   EnumDescriptor_register(protobuf);
   MessageBuilderContext_register(internal);
   OneofBuilderContext_register(internal);
   EnumBuilderContext_register(internal);
+  FileBuilderContext_register(internal);
   Builder_register(internal);
   RepeatedField_register(protobuf);
   Map_register(protobuf);

ruby/ext/google/protobuf_c/protobuf.h

@@ -40,6 +40,7 @@
 // Forward decls.
 struct DescriptorPool;
 struct Descriptor;
+struct FileDescriptor;
 struct FieldDescriptor;
 struct EnumDescriptor;
 struct MessageLayout;
@@ -47,10 +48,12 @@ struct MessageField;
 struct MessageHeader;
 struct MessageBuilderContext;
 struct EnumBuilderContext;
+struct FileBuilderContext;
 struct Builder;
 
 typedef struct DescriptorPool DescriptorPool;
 typedef struct Descriptor Descriptor;
+typedef struct FileDescriptor FileDescriptor;
 typedef struct FieldDescriptor FieldDescriptor;
 typedef struct OneofDescriptor OneofDescriptor;
 typedef struct EnumDescriptor EnumDescriptor;
@@ -60,6 +63,7 @@ typedef struct MessageHeader MessageHeader;
 typedef struct MessageBuilderContext MessageBuilderContext;
 typedef struct OneofBuilderContext OneofBuilderContext;
 typedef struct EnumBuilderContext EnumBuilderContext;
+typedef struct FileBuilderContext FileBuilderContext;
 typedef struct Builder Builder;
 
 /*
@@ -118,6 +122,10 @@ struct Descriptor {
   const upb_handlers* json_serialize_handlers_preserve;
 };
 
+struct FileDescriptor {
+  const upb_filedef* filedef;
+};
+
 struct FieldDescriptor {
   const upb_fielddef* fielddef;
 };
@@ -145,18 +153,27 @@ struct EnumBuilderContext {
   VALUE enumdesc;
 };
 
+struct FileBuilderContext {
+  VALUE pending_list;
+  VALUE file_descriptor;
+  VALUE builder;
+};
+
 struct Builder {
   VALUE pending_list;
+  VALUE default_file_descriptor;
   upb_def** defs;  // used only while finalizing
 };
 
 extern VALUE cDescriptorPool;
 extern VALUE cDescriptor;
+extern VALUE cFileDescriptor;
 extern VALUE cFieldDescriptor;
 extern VALUE cEnumDescriptor;
 extern VALUE cMessageBuilderContext;
 extern VALUE cOneofBuilderContext;
 extern VALUE cEnumBuilderContext;
+extern VALUE cFileBuilderContext;
 extern VALUE cBuilder;
 
 extern VALUE cError;
@@ -175,7 +192,7 @@ VALUE DescriptorPool_alloc(VALUE klass);
 void DescriptorPool_register(VALUE module);
 DescriptorPool* ruby_to_DescriptorPool(VALUE value);
 VALUE DescriptorPool_add(VALUE _self, VALUE def);
-VALUE DescriptorPool_build(VALUE _self);
+VALUE DescriptorPool_build(int argc, VALUE* argv, VALUE _self);
 VALUE DescriptorPool_lookup(VALUE _self, VALUE name);
 VALUE DescriptorPool_generated_pool(VALUE _self);
 
@@ -184,6 +201,7 @@ void Descriptor_free(void* _self);
 VALUE Descriptor_alloc(VALUE klass);
 void Descriptor_register(VALUE module);
 Descriptor* ruby_to_Descriptor(VALUE value);
+VALUE Descriptor_initialize(VALUE _self, VALUE file_descriptor_rb);
 VALUE Descriptor_name(VALUE _self);
 VALUE Descriptor_name_set(VALUE _self, VALUE str);
 VALUE Descriptor_each(VALUE _self);
@@ -193,8 +211,19 @@ VALUE Descriptor_add_oneof(VALUE _self, VALUE obj);
 VALUE Descriptor_each_oneof(VALUE _self);
 VALUE Descriptor_lookup_oneof(VALUE _self, VALUE name);
 VALUE Descriptor_msgclass(VALUE _self);
+VALUE Descriptor_file_descriptor(VALUE _self);
 extern const rb_data_type_t _Descriptor_type;
 
+void FileDescriptor_mark(void* _self);
+void FileDescriptor_free(void* _self);
+VALUE FileDescriptor_alloc(VALUE klass);
+void FileDescriptor_register(VALUE module);
+FileDescriptor* ruby_to_FileDescriptor(VALUE value);
+VALUE FileDescriptor_initialize(int argc, VALUE* argv, VALUE _self);
+VALUE FileDescriptor_name(VALUE _self);
+VALUE FileDescriptor_syntax(VALUE _self);
+VALUE FileDescriptor_syntax_set(VALUE _self, VALUE syntax);
+
 void FieldDescriptor_mark(void* _self);
 void FieldDescriptor_free(void* _self);
 VALUE FieldDescriptor_alloc(VALUE klass);
@@ -204,6 +233,8 @@ VALUE FieldDescriptor_name(VALUE _self);
 VALUE FieldDescriptor_name_set(VALUE _self, VALUE str);
 VALUE FieldDescriptor_type(VALUE _self);
 VALUE FieldDescriptor_type_set(VALUE _self, VALUE type);
+VALUE FieldDescriptor_default(VALUE _self);
+VALUE FieldDescriptor_default_set(VALUE _self, VALUE default_value);
 VALUE FieldDescriptor_label(VALUE _self);
 VALUE FieldDescriptor_label_set(VALUE _self, VALUE label);
 VALUE FieldDescriptor_number(VALUE _self);
@@ -211,6 +242,8 @@ VALUE FieldDescriptor_number_set(VALUE _self, VALUE number);
 VALUE FieldDescriptor_submsg_name(VALUE _self);
 VALUE FieldDescriptor_submsg_name_set(VALUE _self, VALUE value);
 VALUE FieldDescriptor_subtype(VALUE _self);
+VALUE FieldDescriptor_has(VALUE _self, VALUE msg_rb);
+VALUE FieldDescriptor_clear(VALUE _self, VALUE msg_rb);
 VALUE FieldDescriptor_get(VALUE _self, VALUE msg_rb);
 VALUE FieldDescriptor_set(VALUE _self, VALUE msg_rb, VALUE value);
 upb_fieldtype_t ruby_to_fieldtype(VALUE type);
@@ -231,6 +264,8 @@ void EnumDescriptor_free(void* _self);
 VALUE EnumDescriptor_alloc(VALUE klass);
 void EnumDescriptor_register(VALUE module);
 EnumDescriptor* ruby_to_EnumDescriptor(VALUE value);
+VALUE EnumDescriptor_initialize(VALUE _self, VALUE file_descriptor_rb);
+VALUE EnumDescriptor_file_descriptor(VALUE _self);
 VALUE EnumDescriptor_name(VALUE _self);
 VALUE EnumDescriptor_name_set(VALUE _self, VALUE str);
 VALUE EnumDescriptor_add_value(VALUE _self, VALUE name, VALUE number);
@@ -272,12 +307,23 @@ EnumBuilderContext* ruby_to_EnumBuilderContext(VALUE value);
 VALUE EnumBuilderContext_initialize(VALUE _self, VALUE enumdesc);
 VALUE EnumBuilderContext_value(VALUE _self, VALUE name, VALUE number);
 
+void FileBuilderContext_mark(void* _self);
+void FileBuilderContext_free(void* _self);
+VALUE FileBuilderContext_alloc(VALUE klass);
+void FileBuilderContext_register(VALUE module);
+VALUE FileBuilderContext_initialize(VALUE _self, VALUE file_descriptor,
+				    VALUE builder);
+VALUE FileBuilderContext_add_message(VALUE _self, VALUE name);
+VALUE FileBuilderContext_add_enum(VALUE _self, VALUE name);
+VALUE FileBuilderContext_pending_descriptors(VALUE _self);
+
 void Builder_mark(void* _self);
 void Builder_free(void* _self);
 VALUE Builder_alloc(VALUE klass);
 void Builder_register(VALUE module);
 Builder* ruby_to_Builder(VALUE value);
 VALUE Builder_initialize(VALUE _self);
+VALUE Builder_add_file(int argc, VALUE *argv, VALUE _self);
 VALUE Builder_add_message(VALUE _self, VALUE name);
 VALUE Builder_add_enum(VALUE _self, VALUE name);
 VALUE Builder_finalize_to_pool(VALUE _self, VALUE pool_rb);
@@ -443,10 +489,12 @@ VALUE Map_iter_value(Map_iter* iter);
 // -----------------------------------------------------------------------------
 
 #define MESSAGE_FIELD_NO_CASE ((size_t)-1)
+#define MESSAGE_FIELD_NO_HASBIT ((size_t)-1)
 
 struct MessageField {
   size_t offset;
   size_t case_offset;  // for oneofs, a uint32. Else, MESSAGE_FIELD_NO_CASE.
+  size_t hasbit;
 };
 
 struct MessageLayout {
@@ -457,6 +505,9 @@ struct MessageLayout {
 
 MessageLayout* create_layout(const upb_msgdef* msgdef);
 void free_layout(MessageLayout* layout);
+bool field_contains_hasbit(MessageLayout* layout,
+                 const upb_fielddef* field);
+VALUE layout_get_default(const upb_fielddef* field);
 VALUE layout_get(MessageLayout* layout,
                  const void* storage,
                  const upb_fielddef* field);
@@ -464,6 +515,12 @@ void layout_set(MessageLayout* layout,
                 void* storage,
                 const upb_fielddef* field,
                 VALUE val);
+VALUE layout_has(MessageLayout* layout,
+                 const void* storage,
+                 const upb_fielddef* field);
+void layout_clear(MessageLayout* layout,
+                 const void* storage,
+                 const upb_fielddef* field);
 void layout_init(MessageLayout* layout, void* storage);
 void layout_mark(MessageLayout* layout, void* storage);
 void layout_dup(MessageLayout* layout, void* to, void* from);

ruby/tests/basic_proto2.rb

+#!/usr/bin/ruby
+
+# basic_test_pb.rb is in the same directory as this test.
+$LOAD_PATH.unshift(File.expand_path(File.dirname(__FILE__)))
+
+require 'basic_test_proto2_pb'
+require 'common_tests'
+require 'google/protobuf'
+require 'json'
+require 'test/unit'
+
+# ------------- generated code --------------
+
+module BasicTestProto2
+  pool = Google::Protobuf::DescriptorPool.new
+  pool.build do
+    add_file "test_proto2.proto", syntax: :proto2 do
+      add_message "BadFieldNames" do
+        optional :dup, :int32, 1
+        optional :class, :int32, 2
+        optional :"a.b", :int32, 3
+      end
+    end
+  end
+
+  BadFieldNames = pool.lookup("BadFieldNames").msgclass
+
+# ------------ test cases ---------------
+
+  class MessageContainerTest < Test::Unit::TestCase
+    # Required by CommonTests module to resolve proto2 proto classes used in tests.
+    def proto_module
+      ::BasicTestProto2
+    end
+    include CommonTests
+
+    def test_has_field
+      m = TestMessage.new
+      assert_false m.has_optional_int32?
+      assert_false TestMessage.descriptor.lookup('optional_int32').has?(m)
+      assert_false m.has_optional_int64?
+      assert_false TestMessage.descriptor.lookup('optional_int64').has?(m)
+      assert_false m.has_optional_uint32?
+      assert_false TestMessage.descriptor.lookup('optional_uint32').has?(m)
+      assert_false m.has_optional_uint64?
+      assert_false TestMessage.descriptor.lookup('optional_uint64').has?(m)
+      assert_false m.has_optional_bool?
+      assert_false TestMessage.descriptor.lookup('optional_bool').has?(m)
+      assert_false m.has_optional_float?
+      assert_false TestMessage.descriptor.lookup('optional_float').has?(m)
+      assert_false m.has_optional_double?
+      assert_false TestMessage.descriptor.lookup('optional_double').has?(m)
+      assert_false m.has_optional_string?
+      assert_false TestMessage.descriptor.lookup('optional_string').has?(m)
+      assert_false m.has_optional_bytes?
+      assert_false TestMessage.descriptor.lookup('optional_bytes').has?(m)
+      assert_false m.has_optional_enum?
+      assert_false TestMessage.descriptor.lookup('optional_enum').has?(m)
+
+      m = TestMessage.new(:optional_int32 => nil)
+      assert_false m.has_optional_int32?
+
+      assert_raise NoMethodError do
+        m.has_repeated_msg?
+      end
+      assert_raise ArgumentError do
+        TestMessage.descriptor.lookup('repeated_msg').has?(m)
+      end
+
+      m.optional_msg = TestMessage2.new
+      assert_true m.has_optional_msg?
+      assert_true TestMessage.descriptor.lookup('optional_msg').has?(m)
+
+      m = OneofMessage.new
+      assert_false m.has_my_oneof?
+      m.a = "foo"
+      assert_true m.has_a?
+      assert_true OneofMessage.descriptor.lookup('a').has?(m)
+      assert_equal "foo", m.a
+      assert_true m.has_my_oneof?
+      assert_false m.has_b?
+      assert_false OneofMessage.descriptor.lookup('b').has?(m)
+      assert_false m.has_c?
+      assert_false OneofMessage.descriptor.lookup('c').has?(m)
+      assert_false m.has_d?
+      assert_false OneofMessage.descriptor.lookup('d').has?(m)
+
+      m = OneofMessage.new
+      m.b = 100
+      assert_true m.has_b?
+      assert_equal 100, m.b
+      assert_true m.has_my_oneof?
+      assert_false m.has_a?
+      assert_false m.has_c?
+      assert_false m.has_d?
+
+      m = OneofMessage.new
+      m.c = TestMessage2.new
+      assert_true m.has_c?
+      assert_equal TestMessage2.new, m.c
+      assert_true m.has_my_oneof?
+      assert_false m.has_a?
+      assert_false m.has_b?
+      assert_false m.has_d?
+
+      m = OneofMessage.new
+      m.d = :A
+      assert_true m.has_d?
+      assert_equal :A, m.d
+      assert_true m.has_my_oneof?
+      assert_false m.has_a?
+      assert_false m.has_b?
+      assert_false m.has_c?
+    end
+
+    def test_defined_defaults
+      m = TestMessageDefaults.new
+      assert_equal 1, m.optional_int32
+      assert_equal 2, m.optional_int64
+      assert_equal 3, m.optional_uint32
+      assert_equal 4, m.optional_uint64
+      assert_equal true, m.optional_bool
+      assert_equal 6.0, m.optional_float
+      assert_equal 7.0, m.optional_double
+      assert_equal "Default Str", m.optional_string
+      assert_equal "\xCF\xA5s\xBD\xBA\xE6fubar".force_encoding("ASCII-8BIT"), m.optional_bytes
+      assert_equal :B2, m.optional_enum
+
+      assert_false m.has_optional_int32?
+      assert_false m.has_optional_int64?
+      assert_false m.has_optional_uint32?
+      assert_false m.has_optional_uint64?
+      assert_false m.has_optional_bool?
+      assert_false m.has_optional_float?
+      assert_false m.has_optional_double?
+      assert_false m.has_optional_string?
+      assert_false m.has_optional_bytes?
+      assert_false m.has_optional_enum?
+    end
+
+    def test_set_clear_defaults
+      m = TestMessageDefaults.new
+
+      m.optional_int32 = -42
+      assert_equal -42, m.optional_int32
+      assert_true m.has_optional_int32?
+      m.clear_optional_int32
+      assert_equal 1, m.optional_int32
+      assert_false m.has_optional_int32?
+
+      m.optional_string = "foo bar"
+      assert_equal "foo bar", m.optional_string
+      assert_true m.has_optional_string?
+      m.clear_optional_string
+      assert_equal "Default Str", m.optional_string
+      assert_false m.has_optional_string?
+
+      m.optional_msg = TestMessage2.new(:foo => 42)
+      assert_equal TestMessage2.new(:foo => 42), m.optional_msg
+      assert_true m.has_optional_msg?
+
+      m.clear_optional_msg
+      assert_equal nil, m.optional_msg
+      assert_false m.has_optional_msg?
+
+      m.optional_msg = TestMessage2.new(:foo => 42)
+      assert_equal TestMessage2.new(:foo => 42), m.optional_msg
+      assert_true TestMessageDefaults.descriptor.lookup('optional_msg').has?(m)
+
+      TestMessageDefaults.descriptor.lookup('optional_msg').clear(m)
+      assert_equal nil, m.optional_msg
+      assert_false TestMessageDefaults.descriptor.lookup('optional_msg').has?(m)
+
+      m = TestMessage.new
+      m.repeated_int32.push(1)
+      assert_equal [1], m.repeated_int32
+      m.clear_repeated_int32
+      assert_equal [], m.repeated_int32
+
+      m = OneofMessage.new
+      m.a = "foo"
+      assert_equal "foo", m.a
+      assert_true m.has_a?
+      m.clear_a
+      assert_false m.has_a?
+
+      m = OneofMessage.new
+      m.a = "foobar"
+      assert_true m.has_my_oneof?
+      m.clear_my_oneof
+      assert_false m.has_my_oneof?
+
+      m = OneofMessage.new
+      m.a = "bar"
+      assert_equal "bar", m.a
+      assert_true m.has_my_oneof?
+      OneofMessage.descriptor.lookup('a').clear(m)
+      assert_false m.has_my_oneof?
+    end
+
+    def test_initialization_map_errors
+      e = assert_raise ArgumentError do
+        TestMessage.new(:hello => "world")
+      end
+      assert_match(/hello/, e.message)
+
+      e = assert_raise ArgumentError do
+        TestMessage.new(:repeated_uint32 => "hello")
+      end
+      assert_equal e.message, "Expected array as initializer value for repeated field 'repeated_uint32'."
+    end
+
+
+    def test_to_h
+      m = TestMessage.new(:optional_bool => true, :optional_double => -10.100001, :optional_string => 'foo', :repeated_string => ['bar1', 'bar2'])
+      expected_result = {
+        :optional_bool=>true,
+        :optional_double=>-10.100001,
+        :optional_string=>"foo",
+        :repeated_string=>["bar1", "bar2"],
+      }
+      assert_equal expected_result, m.to_h
+
+      m = OneofMessage.new(:a => "foo")
+      expected_result = {:a => "foo"}
+      assert_equal expected_result, m.to_h
+    end
+
+    def test_map_keyword_disabled
+      pool = Google::Protobuf::DescriptorPool.new
+
+      e = assert_raise ArgumentError do
+        pool.build do
+          add_file 'test_file.proto', syntax: :proto2 do
+            add_message "MapMessage" do
+              map :map_string_int32, :string, :int32, 1
+              map :map_string_msg, :string, :message, 2, "TestMessage2"
+            end
+          end
+        end
+      end
+
+      assert_match(/Cannot add a native map/, e.message)
+    end
+
+    def test_respond_to
+      # This test fails with JRuby 1.7.23, likely because of an old JRuby bug.
+      return if RUBY_PLATFORM == "java"
+      msg = TestMessage.new
+      assert !msg.respond_to?(:bacon)
+    end
+
+    def test_file_descriptor
+      file_descriptor = TestMessage.descriptor.file_descriptor
+      assert_true nil != file_descriptor
+      assert_equal "tests/basic_test_proto2.proto", file_descriptor.name
+      assert_equal :proto2, file_descriptor.syntax
+
+      file_descriptor = TestEnum.descriptor.file_descriptor
+      assert_true nil != file_descriptor
+      assert_equal "tests/basic_test_proto2.proto", file_descriptor.name
+      assert_equal :proto2, file_descriptor.syntax
+    end
+  end
+end

ruby/tests/basic_test.proto

+syntax = "proto3";
+
+package basic_test;
+
+message Foo {
+  Bar bar = 1;
+  repeated Baz baz = 2;
+}
+
+message Bar {
+  string msg = 1;
+}
+
+message Baz {
+  string msg = 1;
+}
+
+message TestMessage {
+  int32 optional_int32 = 1;
+  int64 optional_int64 = 2;
+  uint32 optional_uint32 = 3;
+  uint64 optional_uint64 = 4;
+  bool optional_bool = 5;
+  float optional_float = 6;
+  double optional_double = 7;
+  string optional_string = 8;
+  bytes optional_bytes = 9;
+  TestMessage2 optional_msg = 10;
+  TestEnum optional_enum = 11;
+
+  repeated int32 repeated_int32 = 12;
+  repeated int64 repeated_int64 = 13;
+  repeated uint32 repeated_uint32 = 14;
+  repeated uint64 repeated_uint64 = 15;
+  repeated bool repeated_bool = 16;
+  repeated float repeated_float = 17;
+  repeated double repeated_double = 18;
+  repeated string repeated_string = 19;
+  repeated bytes repeated_bytes = 20;
+  repeated TestMessage2 repeated_msg = 21;
+  repeated TestEnum repeated_enum = 22;
+}
+
+message TestMessage2 {
+  int32 foo = 1;
+}
+
+enum TestEnum {
+  Default = 0;
+  A = 1;
+  B = 2;
+  C = 3;
+}
+
+message TestEmbeddedMessageParent {
+  TestEmbeddedMessageChild child_msg = 1;
+  int32 number = 2;
+
+  repeated TestEmbeddedMessageChild repeated_msg = 3;
+  repeated int32 repeated_number = 4;
+}
+
+message TestEmbeddedMessageChild {
+  TestMessage sub_child = 1;
+}
+
+message Recursive1 {
+  Recursive2 foo = 1;
+}
+
+message Recursive2 {
+  Recursive1 foo = 1;
+}
+
+message MapMessage {
+  map<string, int32> map_string_int32 = 1;
+  map<string, TestMessage2> map_string_msg = 2;
+}
+
+message MapMessageWireEquiv {
+  repeated MapMessageWireEquiv_entry1 map_string_int32 = 1;
+  repeated MapMessageWireEquiv_entry2 map_string_msg = 2;
+}
+
+message MapMessageWireEquiv_entry1 {
+  string key = 1;
+  int32 value = 2;
+}
+
+message MapMessageWireEquiv_entry2 {
+  string key = 1;
+  TestMessage2 value = 2;
+}
+
+message OneofMessage {
+  oneof my_oneof {
+    string a = 1;
+    int32 b = 2;
+    TestMessage2 c = 3;
+    TestEnum d = 4;
+  }
+}
+
+message Outer {
+  map<int32, Inner> items = 1;
+}
+
+message Inner {
+}
\ No newline at end of file

ruby/tests/basic_test_proto2.proto

+syntax = "proto2";
+
+package basic_test_proto2;
+
+message Foo {
+  optional Bar bar = 1;
+  repeated Baz baz = 2;
+}
+
+message Bar {
+  optional string msg = 1;
+}
+
+message Baz {
+  optional string msg = 1;
+}
+
+message TestMessage {
+  optional int32 optional_int32 = 1;
+  optional int64 optional_int64 = 2;
+  optional uint32 optional_uint32 = 3;
+  optional uint64 optional_uint64 = 4;
+  optional bool optional_bool = 5;
+  optional float optional_float = 6;
+  optional double optional_double = 7;
+  optional string optional_string = 8;
+  optional bytes optional_bytes = 9;
+  optional TestMessage2 optional_msg = 10;
+  optional TestEnum optional_enum = 11;
+
+  repeated int32 repeated_int32 = 12;
+  repeated int64 repeated_int64 = 13;
+  repeated uint32 repeated_uint32 = 14;
+  repeated uint64 repeated_uint64 = 15;
+  repeated bool repeated_bool = 16;
+  repeated float repeated_float = 17;
+  repeated double repeated_double = 18;
+  repeated string repeated_string = 19;
+  repeated bytes repeated_bytes = 20;
+  repeated TestMessage2 repeated_msg = 21;
+  repeated TestEnum repeated_enum = 22;
+}
+
+message TestMessage2 {
+  optional int32 foo = 1;
+}
+
+message TestMessageDefaults {
+  optional int32 optional_int32 = 1 [default = 1];
+  optional int64 optional_int64 = 2 [default = 2];
+  optional uint32 optional_uint32 = 3 [default = 3];
+  optional uint64 optional_uint64 = 4 [default = 4];
+  optional bool optional_bool = 5 [default = true];
+  optional float optional_float = 6 [default = 6];
+  optional double optional_double = 7 [default = 7];
+  optional string optional_string = 8 [default = "Default Str"];
+  optional bytes optional_bytes = 9 [default = "\xCF\xA5s\xBD\xBA\xE6fubar"];
+  optional TestMessage2 optional_msg = 10;
+  optional TestNonZeroEnum optional_enum = 11 [default = B2];
+}
+
+enum TestEnum {
+  Default = 0;
+  A = 1;
+  B = 2;
+  C = 3;
+}
+
+enum TestNonZeroEnum {
+  A2 = 1;
+  B2 = 2;
+  C2 = 3;
+}
+
+message TestEmbeddedMessageParent {
+  optional TestEmbeddedMessageChild child_msg = 1;
+  optional int32 number = 2;
+
+  repeated TestEmbeddedMessageChild repeated_msg = 3;
+  repeated int32 repeated_number = 4;
+}
+
+message TestEmbeddedMessageChild {
+  optional TestMessage sub_child = 1;
+}
+
+message Recursive1 {
+  optional Recursive2 foo = 1;
+}
+
+message Recursive2 {
+  optional Recursive1 foo = 1;
+}
+
+message MapMessageWireEquiv {
+  repeated MapMessageWireEquiv_entry1 map_string_int32 = 1;
+  repeated MapMessageWireEquiv_entry2 map_string_msg = 2;
+}
+
+message MapMessageWireEquiv_entry1 {
+  optional string key = 1;
+  optional int32 value = 2;
+}
+
+message MapMessageWireEquiv_entry2 {
+  optional string key = 1;
+  optional TestMessage2 value = 2;
+}
+
+message OneofMessage {
+  oneof my_oneof {
+    string a = 1;
+    int32 b = 2;
+    TestMessage2 c = 3;
+    TestEnum d = 4;
+  }
+}

ruby/tests/gc_test.rb

@@ -6,12 +6,13 @@ $LOAD_PATH.unshift(File.expand_path(File.dirname(__FILE__)))
 old_gc = GC.stress
 GC.stress = 0x01 | 0x04
 require 'generated_code_pb'
+require 'generated_code_proto2_pb'
 GC.stress = old_gc
 
 require 'test/unit'
 
 class GCTest < Test::Unit::TestCase
-  def get_msg
+  def get_msg_proto3
     A::B::C::TestMessage.new(
         :optional_int32 => 1,
         :optional_int64 => 1,
@@ -46,12 +47,55 @@ class GCTest < Test::Unit::TestCase
         :map_string_bool => {"a" => true},
     )
   end
+
+  def get_msg_proto2
+    A::B::Proto2::TestMessage.new(
+        :optional_int32 => 1,
+        :optional_int64 => 1,
+        :optional_uint32 => 1,
+        :optional_uint64 => 1,
+        :optional_bool => true,
+        :optional_double => 1.0,
+        :optional_float => 1.0,
+        :optional_string => "a",
+        :optional_bytes => "b",
+        :optional_enum => A::B::Proto2::TestEnum::A,
+        :optional_msg => A::B::Proto2::TestMessage.new(),
+        :repeated_int32 => [1],
+        :repeated_int64 => [1],
+        :repeated_uint32 => [1],
+        :repeated_uint64 => [1],
+        :repeated_bool => [true],
+        :repeated_double => [1.0],
+        :repeated_float => [1.0],
+        :repeated_string => ["a"],
+        :repeated_bytes => ["b"],
+        :repeated_enum => [A::B::Proto2::TestEnum::A],
+        :repeated_msg => [A::B::Proto2::TestMessage.new()],
+        :required_int32 => 1,
+        :required_int64 => 1,
+        :required_uint32 => 1,
+        :required_uint64 => 1,
+        :required_bool => true,
+        :required_double => 1.0,
+        :required_float => 1.0,
+        :required_string => "a",
+        :required_bytes => "b",
+        :required_enum => A::B::Proto2::TestEnum::A,
+        :required_msg => A::B::Proto2::TestMessage.new(),
+    )
+  end
+
   def test_generated_msg
     old_gc = GC.stress
     GC.stress = 0x01 | 0x04
-    from = get_msg
+    from = get_msg_proto3
     data = A::B::C::TestMessage.encode(from)
     to = A::B::C::TestMessage.decode(data)
+
+    from = get_msg_proto2
+    data = A::B::Proto2::TestMessage.encode(from)
+    to = A::B::Proto2::TestMessage.decode(data)
     GC.stress = old_gc
     puts "passed"
   end

ruby/tests/generated_code_proto2.proto

+syntax = "proto2";
+
+package a.b.proto2;
+
+message TestMessage {
+  optional int32 optional_int32 = 1;
+  optional int64 optional_int64 = 2;
+  optional uint32 optional_uint32 = 3;
+  optional uint64 optional_uint64 = 4;
+  optional bool optional_bool = 5;
+  optional double optional_double = 6;
+  optional float optional_float = 7;
+  optional string optional_string = 8;
+  optional bytes optional_bytes = 9;
+  optional TestEnum optional_enum = 10;
+  optional TestMessage optional_msg = 11;
+
+  repeated int32 repeated_int32 = 21;
+  repeated int64 repeated_int64 = 22;
+  repeated uint32 repeated_uint32 = 23;
+  repeated uint64 repeated_uint64 = 24;
+  repeated bool repeated_bool = 25;
+  repeated double repeated_double = 26;
+  repeated float repeated_float = 27;
+  repeated string repeated_string = 28;
+  repeated bytes repeated_bytes = 29;
+  repeated TestEnum repeated_enum = 30;
+  repeated TestMessage repeated_msg = 31;
+
+  required int32 required_int32 = 41;
+  required int64 required_int64 = 42;
+  required uint32 required_uint32 = 43;
+  required uint64 required_uint64 = 44;
+  required bool required_bool = 45;
+  required double required_double = 46;
+  required float required_float = 47;
+  required string required_string = 48;
+  required bytes required_bytes = 49;
+  required TestEnum required_enum = 50;
+  required TestMessage required_msg = 51;
+
+  oneof my_oneof {
+    int32 oneof_int32 = 61;
+    int64 oneof_int64 = 62;
+    uint32 oneof_uint32 = 63;
+    uint64 oneof_uint64 = 64;
+    bool oneof_bool = 65;
+    double oneof_double = 66;
+    float oneof_float = 67;
+    string oneof_string = 68;
+    bytes oneof_bytes = 69;
+    TestEnum oneof_enum = 70;
+    TestMessage oneof_msg = 71;
+  }
+
+  message NestedMessage {
+    optional int32 foo = 1;
+  }
+
+  optional NestedMessage nested_message = 80;
+
+  // Reserved for non-existing field test.
+  // int32 non_exist = 89;
+}
+
+enum TestEnum {
+  Default = 0;
+  A = 1;
+  B = 2;
+  C = 3;
+}
+
+message TestUnknown {
+  optional TestUnknown optional_unknown = 11;
+  repeated TestUnknown repeated_unknown = 31;
+  oneof my_oneof {
+    TestUnknown oneof_unknown = 51;
+  }
+  optional int32 unknown_field = 89;
+}

ruby/tests/generated_code_proto2_test.rb

+#!/usr/bin/ruby
+
+# generated_code.rb is in the same directory as this test.
+$LOAD_PATH.unshift(File.expand_path(File.dirname(__FILE__)))
+
+require 'generated_code_proto2_pb'
+require 'test_import_proto2_pb'
+require 'test_ruby_package_proto2_pb'
+require 'test/unit'
+
+class GeneratedCodeProto2Test < Test::Unit::TestCase
+  def test_generated_msg
+    # just test that we can instantiate the message. The purpose of this test
+    # is to ensure that the output of the code generator is valid Ruby and
+    # successfully creates message definitions and classes, not to test every
+    # aspect of the extension (basic.rb is for that).
+    m = A::B::Proto2::TestMessage.new()
+    m2 = FooBar::Proto2::TestImportedMessage.new()
+    m3 = A::B::Proto2::TestRubyPackageMessage.new()
+  end
+end

ruby/tests/test_import_proto2.proto

+syntax = "proto2";
+
+package foo_bar.proto2;
+
+message TestImportedMessage {}

ruby/tests/test_ruby_package_proto2.proto

+syntax = "proto2";
+
+package foo_bar_proto2;
+
+option ruby_package = "A.B.Proto2";
+
+message TestRubyPackageMessage {}

src/google/protobuf/compiler/ruby/ruby_generated_code_pb.rb

@@ -4,62 +4,64 @@
 require 'google/protobuf'
 
 Google::Protobuf::DescriptorPool.generated_pool.build do
-  add_message "A.B.C.TestMessage" do
-    optional :optional_int32, :int32, 1
-    optional :optional_int64, :int64, 2
-    optional :optional_uint32, :uint32, 3
-    optional :optional_uint64, :uint64, 4
-    optional :optional_bool, :bool, 5
-    optional :optional_double, :double, 6
-    optional :optional_float, :float, 7
-    optional :optional_string, :string, 8
-    optional :optional_bytes, :bytes, 9
-    optional :optional_enum, :enum, 10, "A.B.C.TestEnum"
-    optional :optional_msg, :message, 11, "A.B.C.TestMessage"
-    repeated :repeated_int32, :int32, 21
-    repeated :repeated_int64, :int64, 22
-    repeated :repeated_uint32, :uint32, 23
-    repeated :repeated_uint64, :uint64, 24
-    repeated :repeated_bool, :bool, 25
-    repeated :repeated_double, :double, 26
-    repeated :repeated_float, :float, 27
-    repeated :repeated_string, :string, 28
-    repeated :repeated_bytes, :bytes, 29
-    repeated :repeated_enum, :enum, 30, "A.B.C.TestEnum"
-    repeated :repeated_msg, :message, 31, "A.B.C.TestMessage"
-    map :map_int32_string, :int32, :string, 61
-    map :map_int64_string, :int64, :string, 62
-    map :map_uint32_string, :uint32, :string, 63
-    map :map_uint64_string, :uint64, :string, 64
-    map :map_bool_string, :bool, :string, 65
-    map :map_string_string, :string, :string, 66
-    map :map_string_msg, :string, :message, 67, "A.B.C.TestMessage"
-    map :map_string_enum, :string, :enum, 68, "A.B.C.TestEnum"
-    map :map_string_int32, :string, :int32, 69
-    map :map_string_bool, :string, :bool, 70
-    optional :nested_message, :message, 80, "A.B.C.TestMessage.NestedMessage"
-    oneof :my_oneof do
-      optional :oneof_int32, :int32, 41
-      optional :oneof_int64, :int64, 42
-      optional :oneof_uint32, :uint32, 43
-      optional :oneof_uint64, :uint64, 44
-      optional :oneof_bool, :bool, 45
-      optional :oneof_double, :double, 46
-      optional :oneof_float, :float, 47
-      optional :oneof_string, :string, 48
-      optional :oneof_bytes, :bytes, 49
-      optional :oneof_enum, :enum, 50, "A.B.C.TestEnum"
-      optional :oneof_msg, :message, 51, "A.B.C.TestMessage"
+  add_file("ruby_generated_code.proto", :syntax => :proto3) do
+    add_message "A.B.C.TestMessage" do
+      optional :optional_int32, :int32, 1
+      optional :optional_int64, :int64, 2
+      optional :optional_uint32, :uint32, 3
+      optional :optional_uint64, :uint64, 4
+      optional :optional_bool, :bool, 5
+      optional :optional_double, :double, 6
+      optional :optional_float, :float, 7
+      optional :optional_string, :string, 8
+      optional :optional_bytes, :bytes, 9
+      optional :optional_enum, :enum, 10, "A.B.C.TestEnum"
+      optional :optional_msg, :message, 11, "A.B.C.TestMessage"
+      repeated :repeated_int32, :int32, 21
+      repeated :repeated_int64, :int64, 22
+      repeated :repeated_uint32, :uint32, 23
+      repeated :repeated_uint64, :uint64, 24
+      repeated :repeated_bool, :bool, 25
+      repeated :repeated_double, :double, 26
+      repeated :repeated_float, :float, 27
+      repeated :repeated_string, :string, 28
+      repeated :repeated_bytes, :bytes, 29
+      repeated :repeated_enum, :enum, 30, "A.B.C.TestEnum"
+      repeated :repeated_msg, :message, 31, "A.B.C.TestMessage"
+      map :map_int32_string, :int32, :string, 61
+      map :map_int64_string, :int64, :string, 62
+      map :map_uint32_string, :uint32, :string, 63
+      map :map_uint64_string, :uint64, :string, 64
+      map :map_bool_string, :bool, :string, 65
+      map :map_string_string, :string, :string, 66
+      map :map_string_msg, :string, :message, 67, "A.B.C.TestMessage"
+      map :map_string_enum, :string, :enum, 68, "A.B.C.TestEnum"
+      map :map_string_int32, :string, :int32, 69
+      map :map_string_bool, :string, :bool, 70
+      optional :nested_message, :message, 80, "A.B.C.TestMessage.NestedMessage"
+      oneof :my_oneof do
+        optional :oneof_int32, :int32, 41
+        optional :oneof_int64, :int64, 42
+        optional :oneof_uint32, :uint32, 43
+        optional :oneof_uint64, :uint64, 44
+        optional :oneof_bool, :bool, 45
+        optional :oneof_double, :double, 46
+        optional :oneof_float, :float, 47
+        optional :oneof_string, :string, 48
+        optional :oneof_bytes, :bytes, 49
+        optional :oneof_enum, :enum, 50, "A.B.C.TestEnum"
+        optional :oneof_msg, :message, 51, "A.B.C.TestMessage"
+      end
+    end
+    add_message "A.B.C.TestMessage.NestedMessage" do
+      optional :foo, :int32, 1
+    end
+    add_enum "A.B.C.TestEnum" do
+      value :Default, 0
+      value :A, 1
+      value :B, 2
+      value :C, 3
     end
-  end
-  add_message "A.B.C.TestMessage.NestedMessage" do
-    optional :foo, :int32, 1
-  end
-  add_enum "A.B.C.TestEnum" do
-    value :Default, 0
-    value :A, 1
-    value :B, 2
-    value :C, 3
   end
 end
 

src/google/protobuf/compiler/ruby/ruby_generated_code_proto2.proto

+syntax = "proto2";
+
+package A.B.C;
+
+message TestMessage {
+  optional int32 optional_int32 = 1 [default = 1];
+  optional int64 optional_int64 = 2 [default = 2];
+  optional uint32 optional_uint32 = 3 [default = 3];
+  optional uint64 optional_uint64 = 4 [default = 4];
+  optional bool optional_bool = 5 [default = true];
+  optional double optional_double = 6 [default = 6.0];
+  optional float optional_float = 7 [default = 7.0];
+  optional string optional_string = 8 [default = "default str"];
+  optional bytes optional_bytes = 9 [default = "\0\1\2\100fubar"];
+  optional TestEnum optional_enum = 10 [default = A];
+  optional TestMessage optional_msg = 11;
+
+  repeated int32 repeated_int32 = 21;
+  repeated int64 repeated_int64 = 22;
+  repeated uint32 repeated_uint32 = 23;
+  repeated uint64 repeated_uint64 = 24;
+  repeated bool repeated_bool = 25;
+  repeated double repeated_double = 26;
+  repeated float repeated_float = 27;
+  repeated string repeated_string = 28;
+  repeated bytes repeated_bytes = 29;
+  repeated TestEnum repeated_enum = 30;
+  repeated TestMessage repeated_msg = 31;
+
+  required int32 required_int32 = 41;
+  required int64 required_int64 = 42;
+  required uint32 required_uint32 = 43;
+  required uint64 required_uint64 = 44;
+  required bool required_bool = 45;
+  required double required_double = 46;
+  required float required_float = 47;
+  required string required_string = 48;
+  required bytes required_bytes = 49;
+  required TestEnum required_enum = 50;
+  required TestMessage required_msg = 51;
+
+  oneof my_oneof {
+    int32 oneof_int32 = 61;
+    int64 oneof_int64 = 62;
+    uint32 oneof_uint32 = 63;
+    uint64 oneof_uint64 = 64;
+    bool oneof_bool = 65;
+    double oneof_double = 66;
+    float oneof_float = 67;
+    string oneof_string = 68;
+    bytes oneof_bytes = 69;
+    TestEnum oneof_enum = 70;
+    TestMessage oneof_msg = 71;
+  }
+
+  message NestedMessage {
+    optional int32 foo = 1;
+  }
+
+  optional NestedMessage nested_message = 80;
+}
+
+enum TestEnum {
+  Default = 0;
+  A = 1;
+  B = 2;
+  C = 3;
+}

src/google/protobuf/compiler/ruby/ruby_generated_code_proto2_pb.rb

+# Generated by the protocol buffer compiler.  DO NOT EDIT!
+# source: ruby_generated_code_proto2.proto
+
+require 'google/protobuf'
+
+Google::Protobuf::DescriptorPool.generated_pool.build do
+  add_file("ruby_generated_code_proto2.proto", :syntax => :proto2) do
+    add_message "A.B.C.TestMessage" do
+      optional :optional_int32, :int32, 1, default: 1
+      optional :optional_int64, :int64, 2, default: 2
+      optional :optional_uint32, :uint32, 3, default: 3
+      optional :optional_uint64, :uint64, 4, default: 4
+      optional :optional_bool, :bool, 5, default: true
+      optional :optional_double, :double, 6, default: 6
+      optional :optional_float, :float, 7, default: 7
+      optional :optional_string, :string, 8, default: "default str"
+      optional :optional_bytes, :bytes, 9, default: "\x00\x01\x02\x40\x66\x75\x62\x61\x72".force_encoding("ASCII-8BIT")
+      optional :optional_enum, :enum, 10, "A.B.C.TestEnum", default: 1
+      optional :optional_msg, :message, 11, "A.B.C.TestMessage"
+      repeated :repeated_int32, :int32, 21
+      repeated :repeated_int64, :int64, 22
+      repeated :repeated_uint32, :uint32, 23
+      repeated :repeated_uint64, :uint64, 24
+      repeated :repeated_bool, :bool, 25
+      repeated :repeated_double, :double, 26
+      repeated :repeated_float, :float, 27
+      repeated :repeated_string, :string, 28
+      repeated :repeated_bytes, :bytes, 29
+      repeated :repeated_enum, :enum, 30, "A.B.C.TestEnum"
+      repeated :repeated_msg, :message, 31, "A.B.C.TestMessage"
+      required :required_int32, :int32, 41
+      required :required_int64, :int64, 42
+      required :required_uint32, :uint32, 43
+      required :required_uint64, :uint64, 44
+      required :required_bool, :bool, 45
+      required :required_double, :double, 46
+      required :required_float, :float, 47
+      required :required_string, :string, 48
+      required :required_bytes, :bytes, 49
+      required :required_enum, :enum, 50, "A.B.C.TestEnum"
+      required :required_msg, :message, 51, "A.B.C.TestMessage"
+      optional :nested_message, :message, 80, "A.B.C.TestMessage.NestedMessage"
+      oneof :my_oneof do
+        optional :oneof_int32, :int32, 61
+        optional :oneof_int64, :int64, 62
+        optional :oneof_uint32, :uint32, 63
+        optional :oneof_uint64, :uint64, 64
+        optional :oneof_bool, :bool, 65
+        optional :oneof_double, :double, 66
+        optional :oneof_float, :float, 67
+        optional :oneof_string, :string, 68
+        optional :oneof_bytes, :bytes, 69
+        optional :oneof_enum, :enum, 70, "A.B.C.TestEnum"
+        optional :oneof_msg, :message, 71, "A.B.C.TestMessage"
+      end
+    end
+    add_message "A.B.C.TestMessage.NestedMessage" do
+      optional :foo, :int32, 1
+    end
+    add_enum "A.B.C.TestEnum" do
+      value :Default, 0
+      value :A, 1
+      value :B, 2
+      value :C, 3
+    end
+  end
+end
+
+module A
+  module B
+    module C
+      TestMessage = Google::Protobuf::DescriptorPool.generated_pool.lookup("A.B.C.TestMessage").msgclass
+      TestMessage::NestedMessage = Google::Protobuf::DescriptorPool.generated_pool.lookup("A.B.C.TestMessage.NestedMessage").msgclass
+      TestEnum = Google::Protobuf::DescriptorPool.generated_pool.lookup("A.B.C.TestEnum").enummodule
+    end
+  end
+end

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

@@ -28,6 +28,7 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+#include <iomanip>
 #include <sstream>
 
 #include <google/protobuf/compiler/code_generator.h>
@@ -45,12 +46,13 @@ namespace compiler {
 namespace ruby {
 
 // Forward decls.
-std::string IntToString(int32 value);
+template<class numeric_type> std::string NumberToString(numeric_type value);
 std::string GetRequireName(const std::string& proto_file);
 std::string LabelForField(google::protobuf::FieldDescriptor* field);
 std::string TypeName(google::protobuf::FieldDescriptor* field);
-void GenerateMessage(const google::protobuf::Descriptor* message,
-                     google::protobuf::io::Printer* printer);
+bool GenerateMessage(const google::protobuf::Descriptor* message,
+                     google::protobuf::io::Printer* printer,
+		     std::string* error);
 void GenerateEnum(const google::protobuf::EnumDescriptor* en,
                   google::protobuf::io::Printer* printer);
 void GenerateMessageAssignment(
@@ -61,8 +63,11 @@ void GenerateEnumAssignment(
     const std::string& prefix,
     const google::protobuf::EnumDescriptor* en,
     google::protobuf::io::Printer* printer);
-
-std::string IntToString(int32 value) {
+std::string DefaultValueForField(
+    const google::protobuf::FieldDescriptor* field);
+  
+template<class numeric_type>
+std::string NumberToString(numeric_type value) {
   std::ostringstream os;
   os << value;
   return os.str();
@@ -110,6 +115,62 @@ std::string TypeName(const google::protobuf::FieldDescriptor* field) {
   }
 }
 
+string StringifySyntax(FileDescriptor::Syntax syntax) {
+  switch (syntax) {
+    case FileDescriptor::SYNTAX_PROTO2:
+      return "proto2";
+    case FileDescriptor::SYNTAX_PROTO3:
+      return "proto3";
+    case FileDescriptor::SYNTAX_UNKNOWN:
+    default:
+      GOOGLE_LOG(FATAL) << "Unsupported syntax; this generator only supports "
+	  "proto2 and proto3 syntax.";
+      return "";
+  }
+}
+
+std::string DefaultValueForField(const google::protobuf::FieldDescriptor* field) {
+  switch(field->cpp_type()) {
+    case FieldDescriptor::CPPTYPE_INT32:
+      return NumberToString(field->default_value_int32());
+    case FieldDescriptor::CPPTYPE_INT64:
+      return NumberToString(field->default_value_int64());
+    case FieldDescriptor::CPPTYPE_UINT32:
+      return NumberToString(field->default_value_uint32());
+    case FieldDescriptor::CPPTYPE_UINT64:
+      return NumberToString(field->default_value_uint64());
+    case FieldDescriptor::CPPTYPE_FLOAT:
+      return NumberToString(field->default_value_float());
+    case FieldDescriptor::CPPTYPE_DOUBLE:
+      return NumberToString(field->default_value_double());
+    case FieldDescriptor::CPPTYPE_BOOL:
+      return field->default_value_bool() ? "true" : "false";
+    case FieldDescriptor::CPPTYPE_ENUM:
+      return NumberToString(field->default_value_enum()->number());
+    case FieldDescriptor::CPPTYPE_STRING: {
+      std::ostringstream os;
+      string default_str = field->default_value_string();
+      
+      if (field->type() == FieldDescriptor::TYPE_STRING) {
+        os << "\"" << default_str << "\"";
+      } else if (field->type() == FieldDescriptor::TYPE_BYTES) {
+        os << "\"";
+
+        os.fill('0');
+        for (int i = 0; i < default_str.length(); ++i) {
+          // Write the hex form of each byte.
+          os << "\\x" << std::hex << std::setw(2)
+	     << ((uint16) ((unsigned char) default_str.at(i)));
+        }
+        os << "\".force_encoding(\"ASCII-8BIT\")";
+      }
+
+      return os.str();
+    }
+    default: assert(false); return "";
+  }
+}
+
 void GenerateField(const google::protobuf::FieldDescriptor* field,
                    google::protobuf::io::Printer* printer) {
 
@@ -124,7 +185,7 @@ void GenerateField(const google::protobuf::FieldDescriptor* field,
       "name", field->name(),
       "key_type", TypeName(key_field),
       "value_type", TypeName(value_field),
-      "number", IntToString(field->number()));
+      "number", NumberToString(field->number()));
 
     if (value_field->cpp_type() == FieldDescriptor::CPPTYPE_MESSAGE) {
       printer->Print(
@@ -146,19 +207,25 @@ void GenerateField(const google::protobuf::FieldDescriptor* field,
     printer->Print(
       ":$type$, $number$",
       "type", TypeName(field),
-      "number", IntToString(field->number()));
+      "number", NumberToString(field->number()));
 
     if (field->cpp_type() == FieldDescriptor::CPPTYPE_MESSAGE) {
       printer->Print(
-        ", \"$subtype$\"\n",
+        ", \"$subtype$\"",
        "subtype", field->message_type()->full_name());
     } else if (field->cpp_type() == FieldDescriptor::CPPTYPE_ENUM) {
       printer->Print(
-        ", \"$subtype$\"\n",
+        ", \"$subtype$\"",
         "subtype", field->enum_type()->full_name());
-    } else {
-      printer->Print("\n");
     }
+
+    if (field->has_default_value()) {
+      printer->Print(
+	", default: $default$",
+	"default", DefaultValueForField(field));
+    }
+    
+    printer->Print("\n");
   }
 }
 
@@ -178,13 +245,18 @@ void GenerateOneof(const google::protobuf::OneofDescriptor* oneof,
   printer->Print("end\n");
 }
 
-void GenerateMessage(const google::protobuf::Descriptor* message,
-                     google::protobuf::io::Printer* printer) {
-
+bool GenerateMessage(const google::protobuf::Descriptor* message,
+                     google::protobuf::io::Printer* printer,
+		     std::string* error) {
+  if (message->extension_range_count() > 0 || message->extension_count() > 0) {
+    *error = "Extensions are not yet supported for proto2 .proto files.";
+    return false;
+  }
+  
   // Don't generate MapEntry messages -- we use the Ruby extension's native
   // support for map fields instead.
   if (message->options().map_entry()) {
-    return;
+    return true;
   }
 
   printer->Print(
@@ -208,11 +280,15 @@ void GenerateMessage(const google::protobuf::Descriptor* message,
   printer->Print("end\n");
 
   for (int i = 0; i < message->nested_type_count(); i++) {
-    GenerateMessage(message->nested_type(i), printer);
+    if (!GenerateMessage(message->nested_type(i), printer, error)) {
+      return false;
+    }
   }
   for (int i = 0; i < message->enum_type_count(); i++) {
     GenerateEnum(message->enum_type(i), printer);
   }
+
+  return true;
 }
 
 void GenerateEnum(const google::protobuf::EnumDescriptor* en,
@@ -227,7 +303,7 @@ void GenerateEnum(const google::protobuf::EnumDescriptor* en,
     printer->Print(
       "value :$name$, $number$\n",
       "name", value->name(),
-      "number", IntToString(value->number()));
+      "number", NumberToString(value->number()));
   }
 
   printer->Outdent();
@@ -423,7 +499,8 @@ bool MaybeEmitDependency(const FileDescriptor* import,
                          const FileDescriptor* from,
                          io::Printer* printer,
                          string* error) {
-  if (import->syntax() == FileDescriptor::SYNTAX_PROTO2) {
+  if (from->syntax() == FileDescriptor::SYNTAX_PROTO3 &&
+      import->syntax() == FileDescriptor::SYNTAX_PROTO2) {
     for (int i = 0; i < from->message_type_count(); i++) {
       if (UsesTypeFromFile(from->message_type(i), import, error)) {
         // Error text was already set by UsesTypeFromFile().
@@ -462,16 +539,29 @@ bool GenerateFile(const FileDescriptor* file, io::Printer* printer,
     }
   }
 
-  printer->Print(
-    "Google::Protobuf::DescriptorPool.generated_pool.build do\n");
+  // TODO: Remove this when ruby supports extensions for proto2 syntax.
+  if (file->extension_count() > 0) {
+    *error = "Extensions are not yet supported for proto2 .proto files.";
+    return false;
+  }
+
+  printer->Print("Google::Protobuf::DescriptorPool.generated_pool.build do\n");
+  printer->Indent();
+  printer->Print("add_file(\"$filename$\", :syntax => :$syntax$) do\n",
+		 "filename", file->name(), "syntax",
+		 StringifySyntax(file->syntax()));
   printer->Indent();
   for (int i = 0; i < file->message_type_count(); i++) {
-    GenerateMessage(file->message_type(i), printer);
+    if (!GenerateMessage(file->message_type(i), printer, error)) {
+      return false;
+    }
   }
   for (int i = 0; i < file->enum_type_count(); i++) {
     GenerateEnum(file->enum_type(i), printer);
   }
   printer->Outdent();
+  printer->Print("end\n");
+  printer->Outdent();
   printer->Print(
     "end\n\n");
 
@@ -492,10 +582,9 @@ bool Generator::Generate(
     GeneratorContext* generator_context,
     string* error) const {
 
-  if (file->syntax() != FileDescriptor::SYNTAX_PROTO3) {
-    *error =
-        "Can only generate Ruby code for proto3 .proto files.\n"
-        "Please add 'syntax = \"proto3\";' to the top of your .proto file.\n";
+  if (file->syntax() != FileDescriptor::SYNTAX_PROTO3 &&
+      file->syntax() != FileDescriptor::SYNTAX_PROTO2) {
+    *error = "Invalid or unsupported proto syntax";
     return false;
   }
 

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

@@ -56,7 +56,7 @@ string FindRubyTestDir() {
 // Some day, we may integrate build systems between protoc and the language
 // extensions to the point where we can do this test in a more automated way.
 
-TEST(RubyGeneratorTest, GeneratorTest) {
+TEST(RubyGeneratorTest, Proto3GeneratorTest) {
   string ruby_tests = FindRubyTestDir();
 
   google::protobuf::compiler::CommandLineInterface cli;
@@ -102,6 +102,52 @@ TEST(RubyGeneratorTest, GeneratorTest) {
   EXPECT_EQ(expected_output, output);
 }
 
+TEST(RubyGeneratorTest, Proto2GeneratorTest) {
+  string ruby_tests = FindRubyTestDir();
+
+  google::protobuf::compiler::CommandLineInterface cli;
+  cli.SetInputsAreProtoPathRelative(true);
+
+  ruby::Generator ruby_generator;
+  cli.RegisterGenerator("--ruby_out", &ruby_generator, "");
+
+  // Copy generated_code.proto to the temporary test directory.
+  string test_input;
+  GOOGLE_CHECK_OK(File::GetContents(
+      ruby_tests + "/ruby_generated_code_proto2.proto",
+      &test_input,
+      true));
+  GOOGLE_CHECK_OK(File::SetContents(
+      TestTempDir() + "/ruby_generated_code_proto2.proto",
+      test_input,
+      true));
+
+  // Invoke the proto compiler (we will be inside TestTempDir() at this point).
+  string ruby_out = "--ruby_out=" + TestTempDir();
+  string proto_path = "--proto_path=" + TestTempDir();
+  const char* argv[] = {
+    "protoc",
+    ruby_out.c_str(),
+    proto_path.c_str(),
+    "ruby_generated_code_proto2.proto",
+  };
+
+  EXPECT_EQ(0, cli.Run(4, argv));
+
+  // Load the generated output and compare to the expected result.
+  string output;
+  GOOGLE_CHECK_OK(File::GetContents(
+      TestTempDir() + "/ruby_generated_code_proto2_pb.rb",
+      &output,
+      true));
+  string expected_output;
+  GOOGLE_CHECK_OK(File::GetContents(
+      ruby_tests + "/ruby_generated_code_proto2_pb.rb",
+      &expected_output,
+      true));
+  EXPECT_EQ(expected_output, output);
+}
+
 }  // namespace
 }  // namespace ruby
 }  // namespace compiler