Support ObjC Generic Collections

- Extend GPB*ObjectDictionary to support generic syntax.
- Update the generator to output generics so the enclosed type is exposed for compiler checks.
- Use generics in a the public interfaces.
- Update the generated sources that are checked in.

17 files changed, 236 insertions, 131 deletions

diff --git a/src/google/protobuf/compiler/objectivec/objectivec_enum_field.cc b/src/google/protobuf/compiler/objectivec/objectivec_enum_field.cc
index 30a13ddb..ecc77f6b 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_enum_field.cc
+++ b/src/google/protobuf/compiler/objectivec/objectivec_enum_field.cc
@@ -44,6 +44,7 @@ namespace compiler {
 namespace objectivec {
 
 namespace {
+
 void SetEnumVariables(const FieldDescriptor* descriptor,
                       map<string, string>* variables) {
   string type = EnumName(descriptor->enum_type());
@@ -63,8 +64,9 @@ void SetEnumVariables(const FieldDescriptor* descriptor,
 }
 }  // namespace
 
-EnumFieldGenerator::EnumFieldGenerator(const FieldDescriptor* descriptor)
-    : SingleFieldGenerator(descriptor) {
+EnumFieldGenerator::EnumFieldGenerator(const FieldDescriptor* descriptor,
+                                       const Options& options)
+    : SingleFieldGenerator(descriptor, options) {
   SetEnumVariables(descriptor, &variables_);
 }
 
@@ -112,6 +114,7 @@ void EnumFieldGenerator::GenerateCFunctionImplementations(
 
 void EnumFieldGenerator::DetermineForwardDeclarations(
     set<string>* fwd_decls) const {
+  SingleFieldGenerator::DetermineForwardDeclarations(fwd_decls);
   // If it is an enum defined in a different file, then we'll need a forward
   // declaration for it.  When it is in our file, all the enums are output
   // before the message, so it will be declared before it is needed.
@@ -123,14 +126,20 @@ void EnumFieldGenerator::DetermineForwardDeclarations(
 }
 
 RepeatedEnumFieldGenerator::RepeatedEnumFieldGenerator(
-    const FieldDescriptor* descriptor)
-    : RepeatedFieldGenerator(descriptor) {
+    const FieldDescriptor* descriptor, const Options& options)
+    : RepeatedFieldGenerator(descriptor, options) {
   SetEnumVariables(descriptor, &variables_);
   variables_["array_storage_type"] = "GPBEnumArray";
 }
 
 RepeatedEnumFieldGenerator::~RepeatedEnumFieldGenerator() {}
 
+void RepeatedEnumFieldGenerator::FinishInitialization(void) {
+  RepeatedFieldGenerator::FinishInitialization();
+  variables_["array_comment"] =
+      "// |" + variables_["name"] + "| contains |" + variables_["storage_type"] + "|\n";
+}
+
 void RepeatedEnumFieldGenerator::GenerateFieldDescriptionTypeSpecific(
     io::Printer* printer) const {
   printer->Print(
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_enum_field.h b/src/google/protobuf/compiler/objectivec/objectivec_enum_field.h
index b629eae8..ae2f57e3 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_enum_field.h
+++ b/src/google/protobuf/compiler/objectivec/objectivec_enum_field.h
@@ -41,7 +41,8 @@ namespace compiler {
 namespace objectivec {
 
 class EnumFieldGenerator : public SingleFieldGenerator {
-  friend FieldGenerator* FieldGenerator::Make(const FieldDescriptor* field);
+  friend FieldGenerator* FieldGenerator::Make(const FieldDescriptor* field,
+                                              const Options& options);
 
  public:
   virtual void GenerateFieldDescriptionTypeSpecific(io::Printer* printer) const;
@@ -50,7 +51,7 @@ class EnumFieldGenerator : public SingleFieldGenerator {
   virtual void DetermineForwardDeclarations(set<string>* fwd_decls) const;
 
  protected:
-  explicit EnumFieldGenerator(const FieldDescriptor* descriptor);
+  EnumFieldGenerator(const FieldDescriptor* descriptor, const Options& options);
   virtual ~EnumFieldGenerator();
 
  private:
@@ -58,13 +59,16 @@ class EnumFieldGenerator : public SingleFieldGenerator {
 };
 
 class RepeatedEnumFieldGenerator : public RepeatedFieldGenerator {
-  friend FieldGenerator* FieldGenerator::Make(const FieldDescriptor* field);
+  friend FieldGenerator* FieldGenerator::Make(const FieldDescriptor* field,
+                                              const Options& options);
 
  public:
+  virtual void FinishInitialization();
   virtual void GenerateFieldDescriptionTypeSpecific(io::Printer* printer) const;
 
  protected:
-  RepeatedEnumFieldGenerator(const FieldDescriptor* descriptor);
+  RepeatedEnumFieldGenerator(const FieldDescriptor* descriptor,
+                             const Options& options);
   virtual ~RepeatedEnumFieldGenerator();
 
  private:
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_field.cc b/src/google/protobuf/compiler/objectivec/objectivec_field.cc
index cf5d8cfb..09341820 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_field.cc
+++ b/src/google/protobuf/compiler/objectivec/objectivec_field.cc
@@ -45,6 +45,7 @@ namespace compiler {
 namespace objectivec {
 
 namespace {
+
 void SetCommonFieldVariables(const FieldDescriptor* descriptor,
                              map<string, string>* variables) {
   string camel_case_name = FieldName(descriptor);
@@ -117,39 +118,40 @@ void SetCommonFieldVariables(const FieldDescriptor* descriptor,
 
 }  // namespace
 
-FieldGenerator* FieldGenerator::Make(const FieldDescriptor* field) {
+FieldGenerator* FieldGenerator::Make(const FieldDescriptor* field,
+                                     const Options& options) {
   FieldGenerator* result = NULL;
   if (field->is_repeated()) {
     switch (GetObjectiveCType(field)) {
       case OBJECTIVECTYPE_MESSAGE: {
         if (field->is_map()) {
-          result = new MapFieldGenerator(field);
+          result = new MapFieldGenerator(field, options);
         } else {
-          result = new RepeatedMessageFieldGenerator(field);
+          result = new RepeatedMessageFieldGenerator(field, options);
         }
         break;
       }
       case OBJECTIVECTYPE_ENUM:
-        result = new RepeatedEnumFieldGenerator(field);
+        result = new RepeatedEnumFieldGenerator(field, options);
         break;
       default:
-        result = new RepeatedPrimitiveFieldGenerator(field);
+        result = new RepeatedPrimitiveFieldGenerator(field, options);
         break;
     }
   } else {
     switch (GetObjectiveCType(field)) {
       case OBJECTIVECTYPE_MESSAGE: {
-        result = new MessageFieldGenerator(field);
+        result = new MessageFieldGenerator(field, options);
         break;
       }
       case OBJECTIVECTYPE_ENUM:
-        result = new EnumFieldGenerator(field);
+        result = new EnumFieldGenerator(field, options);
         break;
       default:
         if (IsReferenceType(field)) {
-          result = new PrimitiveObjFieldGenerator(field);
+          result = new PrimitiveObjFieldGenerator(field, options);
         } else {
-          result = new PrimitiveFieldGenerator(field);
+          result = new PrimitiveFieldGenerator(field, options);
         }
         break;
     }
@@ -158,8 +160,8 @@ FieldGenerator* FieldGenerator::Make(const FieldDescriptor* field) {
   return result;
 }
 
-
-FieldGenerator::FieldGenerator(const FieldDescriptor* descriptor)
+FieldGenerator::FieldGenerator(const FieldDescriptor* descriptor,
+                               const Options& options)
     : descriptor_(descriptor) {
   SetCommonFieldVariables(descriptor, &variables_);
 }
@@ -252,9 +254,9 @@ void FieldGenerator::FinishInitialization(void) {
   }
 }
 
-SingleFieldGenerator::SingleFieldGenerator(
-    const FieldDescriptor* descriptor)
-    : FieldGenerator(descriptor) {
+SingleFieldGenerator::SingleFieldGenerator(const FieldDescriptor* descriptor,
+                                           const Options& options)
+    : FieldGenerator(descriptor, options) {
   // Nothing
 }
 
@@ -300,9 +302,9 @@ bool SingleFieldGenerator::WantsHasProperty(void) const {
   return false;
 }
 
-ObjCObjFieldGenerator::ObjCObjFieldGenerator(
-    const FieldDescriptor* descriptor)
-    : SingleFieldGenerator(descriptor) {
+ObjCObjFieldGenerator::ObjCObjFieldGenerator(const FieldDescriptor* descriptor,
+                                             const Options& options)
+    : SingleFieldGenerator(descriptor, options) {
   variables_["property_storage_attribute"] = "strong";
   if (IsRetainedName(variables_["name"])) {
     variables_["storage_attribute"] = " NS_RETURNS_NOT_RETAINED";
@@ -342,18 +344,21 @@ void ObjCObjFieldGenerator::GeneratePropertyDeclaration(
 }
 
 RepeatedFieldGenerator::RepeatedFieldGenerator(
-    const FieldDescriptor* descriptor)
-    : ObjCObjFieldGenerator(descriptor) {
+    const FieldDescriptor* descriptor, const Options& options)
+    : ObjCObjFieldGenerator(descriptor, options) {
   // Repeated fields don't use the has index.
   variables_["has_index"] = "GPBNoHasBit";
+  // Default to no comment and let the cases needing it fill it in.
+  variables_["array_comment"] = "";
 }
 
 RepeatedFieldGenerator::~RepeatedFieldGenerator() {}
 
 void RepeatedFieldGenerator::FinishInitialization(void) {
   FieldGenerator::FinishInitialization();
-  variables_["array_comment"] =
-      "// |" + variables_["name"] + "| contains |" + variables_["storage_type"] + "|\n";
+  if (variables_.find("array_property_type") == variables_.end()) {
+    variables_["array_property_type"] = variable("array_storage_type");
+  }
 }
 
 void RepeatedFieldGenerator::GenerateFieldStorageDeclaration(
@@ -379,13 +384,13 @@ void RepeatedFieldGenerator::GeneratePropertyDeclaration(
       variables_,
       "$comments$"
       "$array_comment$"
-      "@property(nonatomic, readwrite, strong, null_resettable) $array_storage_type$ *$name$$storage_attribute$;\n"
+      "@property(nonatomic, readwrite, strong, null_resettable) $array_property_type$ *$name$$storage_attribute$;\n"
       "@property(nonatomic, readonly) NSUInteger $name$_Count;\n");
   if (IsInitName(variables_.find("name")->second)) {
     // If property name starts with init we need to annotate it to get past ARC.
     // http://stackoverflow.com/questions/18723226/how-do-i-annotate-an-objective-c-property-with-an-objc-method-family/18723227#18723227
     printer->Print(variables_,
-                   "- ($array_storage_type$ *)$name$ GPB_METHOD_FAMILY_NONE;\n");
+                   "- ($array_property_type$ *)$name$ GPB_METHOD_FAMILY_NONE;\n");
   }
   printer->Print("\n");
 }
@@ -395,7 +400,8 @@ bool RepeatedFieldGenerator::WantsHasProperty(void) const {
   return false;
 }
 
-FieldGeneratorMap::FieldGeneratorMap(const Descriptor* descriptor)
+FieldGeneratorMap::FieldGeneratorMap(const Descriptor* descriptor,
+                                     const Options& options)
     : descriptor_(descriptor),
       field_generators_(
           new scoped_ptr<FieldGenerator>[descriptor->field_count()]),
@@ -403,10 +409,12 @@ FieldGeneratorMap::FieldGeneratorMap(const Descriptor* descriptor)
           new scoped_ptr<FieldGenerator>[descriptor->extension_count()]) {
   // Construct all the FieldGenerators.
   for (int i = 0; i < descriptor->field_count(); i++) {
-    field_generators_[i].reset(FieldGenerator::Make(descriptor->field(i)));
+    field_generators_[i].reset(
+        FieldGenerator::Make(descriptor->field(i), options));
   }
   for (int i = 0; i < descriptor->extension_count(); i++) {
-    extension_generators_[i].reset(FieldGenerator::Make(descriptor->extension(i)));
+    extension_generators_[i].reset(
+        FieldGenerator::Make(descriptor->extension(i), options));
   }
 }
 
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_field.h b/src/google/protobuf/compiler/objectivec/objectivec_field.h
index 130a52dd..e8a20a72 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_field.h
+++ b/src/google/protobuf/compiler/objectivec/objectivec_field.h
@@ -49,24 +49,31 @@ namespace objectivec {
 
 class FieldGenerator {
  public:
-  static FieldGenerator* Make(const FieldDescriptor* field);
+  static FieldGenerator* Make(const FieldDescriptor* field,
+                              const Options& options);
 
   virtual ~FieldGenerator();
 
+  // Exposed for subclasses to fill in.
   virtual void GenerateFieldStorageDeclaration(io::Printer* printer) const = 0;
   virtual void GeneratePropertyDeclaration(io::Printer* printer) const = 0;
-
   virtual void GeneratePropertyImplementation(io::Printer* printer) const = 0;
 
-  virtual void GenerateFieldDescription(io::Printer* printer) const;
+  // Called by GenerateFieldDescription, exposed for classes that need custom
+  // generation.
   virtual void GenerateFieldDescriptionTypeSpecific(io::Printer* printer) const;
-  virtual void GenerateFieldNumberConstant(io::Printer* printer) const;
 
+  // Exposed for subclasses to extend, base does nothing.
   virtual void GenerateCFunctionDeclarations(io::Printer* printer) const;
   virtual void GenerateCFunctionImplementations(io::Printer* printer) const;
 
+  // Exposed for subclasses, should always call it on the parent class also.
   virtual void DetermineForwardDeclarations(set<string>* fwd_decls) const;
 
+  // Used during generation, not intended to be extended by subclasses.
+  void GenerateFieldDescription(io::Printer* printer) const;
+  void GenerateFieldNumberConstant(io::Printer* printer) const;
+
   void SetOneofIndexBase(int index_base);
 
   string variable(const char* key) const {
@@ -81,7 +88,7 @@ class FieldGenerator {
   string raw_field_name() const { return variable("raw_field_name"); }
 
  protected:
-  explicit FieldGenerator(const FieldDescriptor* descriptor);
+  FieldGenerator(const FieldDescriptor* descriptor, const Options& options);
 
   virtual void FinishInitialization(void);
   virtual bool WantsHasProperty(void) const = 0;
@@ -103,7 +110,8 @@ class SingleFieldGenerator : public FieldGenerator {
   virtual void GeneratePropertyImplementation(io::Printer* printer) const;
 
  protected:
-  explicit SingleFieldGenerator(const FieldDescriptor* descriptor);
+  SingleFieldGenerator(const FieldDescriptor* descriptor,
+                       const Options& options);
   virtual bool WantsHasProperty(void) const;
 
  private:
@@ -119,7 +127,8 @@ class ObjCObjFieldGenerator : public SingleFieldGenerator {
   virtual void GeneratePropertyDeclaration(io::Printer* printer) const;
 
  protected:
-  explicit ObjCObjFieldGenerator(const FieldDescriptor* descriptor);
+  ObjCObjFieldGenerator(const FieldDescriptor* descriptor,
+                        const Options& options);
 
  private:
   GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(ObjCObjFieldGenerator);
@@ -135,7 +144,8 @@ class RepeatedFieldGenerator : public ObjCObjFieldGenerator {
   virtual void GeneratePropertyImplementation(io::Printer* printer) const;
 
  protected:
-  explicit RepeatedFieldGenerator(const FieldDescriptor* descriptor);
+  RepeatedFieldGenerator(const FieldDescriptor* descriptor,
+                         const Options& options);
   virtual void FinishInitialization(void);
   virtual bool WantsHasProperty(void) const;
 
@@ -146,7 +156,7 @@ class RepeatedFieldGenerator : public ObjCObjFieldGenerator {
 // Convenience class which constructs FieldGenerators for a Descriptor.
 class FieldGeneratorMap {
  public:
-  explicit FieldGeneratorMap(const Descriptor* descriptor);
+  FieldGeneratorMap(const Descriptor* descriptor, const Options& options);
   ~FieldGeneratorMap();
 
   const FieldGenerator& get(const FieldDescriptor* field) const;
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_file.cc b/src/google/protobuf/compiler/objectivec/objectivec_file.cc
index 228c66f0..cdf9ebbc 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_file.cc
+++ b/src/google/protobuf/compiler/objectivec/objectivec_file.cc
@@ -50,17 +50,18 @@ const int32 GOOGLE_PROTOBUF_OBJC_GEN_VERSION = 30000;
 namespace compiler {
 namespace objectivec {
 
-FileGenerator::FileGenerator(const FileDescriptor *file)
+FileGenerator::FileGenerator(const FileDescriptor *file, const Options& options)
     : file_(file),
       root_class_name_(FileClassName(file)),
-      is_public_dep_(false) {
+      is_public_dep_(false),
+      options_(options) {
   for (int i = 0; i < file_->enum_type_count(); i++) {
     EnumGenerator *generator = new EnumGenerator(file_->enum_type(i));
     enum_generators_.push_back(generator);
   }
   for (int i = 0; i < file_->message_type_count(); i++) {
     MessageGenerator *generator =
-        new MessageGenerator(root_class_name_, file_->message_type(i));
+        new MessageGenerator(root_class_name_, file_->message_type(i), options_);
     message_generators_.push_back(generator);
   }
   for (int i = 0; i < file_->extension_count(); i++) {
@@ -352,7 +353,8 @@ const vector<FileGenerator *> &FileGenerator::DependencyGenerators() {
       public_import_names.insert(file_->public_dependency(i)->name());
     }
     for (int i = 0; i < file_->dependency_count(); i++) {
-      FileGenerator *generator = new FileGenerator(file_->dependency(i));
+      FileGenerator *generator =
+          new FileGenerator(file_->dependency(i), options_);
       const string& name = file_->dependency(i)->name();
       bool public_import = (public_import_names.count(name) != 0);
       generator->SetIsPublicDependency(public_import);
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_file.h b/src/google/protobuf/compiler/objectivec/objectivec_file.h
index 1bb4f0ea..4c0fcd3f 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_file.h
+++ b/src/google/protobuf/compiler/objectivec/objectivec_file.h
@@ -55,7 +55,7 @@ class MessageGenerator;
 
 class FileGenerator {
  public:
-  explicit FileGenerator(const FileDescriptor* file);
+  FileGenerator(const FileDescriptor* file, const Options& options);
   ~FileGenerator();
 
   void GenerateSource(io::Printer* printer);
@@ -84,6 +84,8 @@ class FileGenerator {
   vector<ExtensionGenerator*> extension_generators_;
   bool is_public_dep_;
 
+  const Options options_;
+
   const vector<FileGenerator*>& DependencyGenerators();
 
   GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(FileGenerator);
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_generator.cc b/src/google/protobuf/compiler/objectivec/objectivec_generator.cc
index 375b4e0f..72e295de 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_generator.cc
+++ b/src/google/protobuf/compiler/objectivec/objectivec_generator.cc
@@ -49,21 +49,31 @@ bool ObjectiveCGenerator::Generate(const FileDescriptor* file,
                                    const string& parameter,
                                    OutputDirectory* output_directory,
                                    string* error) const {
-  // ObjC doesn't have any options at the moment, error if passed one.
+  // -----------------------------------------------------------------
+  // Parse generator options.
+
+  Options generation_options;
+
   vector<pair<string, string> > options;
   ParseGeneratorParameter(parameter, &options);
   for (int i = 0; i < options.size(); i++) {
-    *error = "error:: Unknown generator option: " + options[i].first;
-    return false;
+    if (options[i].first == "expected_prefixes_path") {
+      generation_options.expected_prefixes_path = options[i].second;
+    } else {
+      *error = "error: Unknown generator option: " + options[i].first;
+      return false;
+    }
   }
 
+  // -----------------------------------------------------------------
+
   // Validate the objc prefix/package pairing.
-  if (!ValidateObjCClassPrefix(file, error)) {
+  if (!ValidateObjCClassPrefix(file, generation_options, error)) {
     // *error will have been filled in.
     return false;
   }
 
-  FileGenerator file_generator(file);
+  FileGenerator file_generator(file, generation_options);
   string filepath = FilePath(file);
 
   // Generate header.
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_helpers.cc b/src/google/protobuf/compiler/objectivec/objectivec_helpers.cc
index 8527b74b..77a378c8 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_helpers.cc
+++ b/src/google/protobuf/compiler/objectivec/objectivec_helpers.cc
@@ -58,6 +58,14 @@ namespace protobuf {
 namespace compiler {
 namespace objectivec {
 
+Options::Options() {
+  // Default is the value of the env for the package prefixes.
+  const char* file_path = getenv("GPB_OBJC_EXPECTED_PACKAGE_PREFIXES");
+  if (file_path) {
+    expected_prefixes_path = file_path;
+  }
+}
+
 namespace {
 
 hash_set<string> MakeWordsMap(const char* const words[], size_t num_words) {
@@ -890,26 +898,26 @@ bool Parser::ParseLoop() {
   return true;
 }
 
-bool LoadExpectedPackagePrefixes(map<string, string>* prefix_map,
-                                 string* out_expect_file_path,
+bool LoadExpectedPackagePrefixes(const Options &generation_options,
+                                 map<string, string>* prefix_map,
                                  string* out_error) {
-  const char* file_path = getenv("GPB_OBJC_EXPECTED_PACKAGE_PREFIXES");
-  if (file_path == NULL) {
+  if (generation_options.expected_prefixes_path.empty()) {
     return true;
   }
 
   int fd;
   do {
-    fd = open(file_path, O_RDONLY);
+    fd = open(generation_options.expected_prefixes_path.c_str(), O_RDONLY);
   } while (fd < 0 && errno == EINTR);
   if (fd < 0) {
     *out_error =
-        string(file_path) + ":0:0: error: Unable to open." + strerror(errno);
+        string("error: Unable to open \"") +
+        generation_options.expected_prefixes_path +
+        "\", " + strerror(errno);
     return false;
   }
   io::FileInputStream file_stream(fd);
   file_stream.SetCloseOnDelete(true);
-  *out_expect_file_path = file_path;
 
   Parser parser(prefix_map);
   const void* buf;
@@ -920,8 +928,9 @@ bool LoadExpectedPackagePrefixes(map<string, string>* prefix_map,
     }
 
     if (!parser.ParseChunk(StringPiece(static_cast<const char*>(buf), buf_len))) {
-      *out_error = string(file_path) + ":" + SimpleItoa(parser.last_line()) +
-                   ":0: error: " + parser.error_str();
+      *out_error =
+          string("error: ") + generation_options.expected_prefixes_path +
+          " Line " + SimpleItoa(parser.last_line()) + ", " + parser.error_str();
       return false;
     }
   }
@@ -930,7 +939,9 @@ bool LoadExpectedPackagePrefixes(map<string, string>* prefix_map,
 
 }  // namespace
 
-bool ValidateObjCClassPrefix(const FileDescriptor* file, string* out_error) {
+bool ValidateObjCClassPrefix(const FileDescriptor* file,
+                             const Options& generation_options,
+                             string* out_error) {
   const string prefix = file->options().objc_class_prefix();
   const string package = file->package();
 
@@ -939,11 +950,10 @@ bool ValidateObjCClassPrefix(const FileDescriptor* file, string* out_error) {
 
   // Load any expected package prefixes to validate against those.
   map<string, string> expected_package_prefixes;
-  string expect_file_path;
-  if (!LoadExpectedPackagePrefixes(&expected_package_prefixes,
-                                   &expect_file_path, out_error)) {
-    // Any error, clear the entries that were read.
-    expected_package_prefixes.clear();
+  if (!LoadExpectedPackagePrefixes(generation_options,
+                                   &expected_package_prefixes,
+                                   out_error)) {
+    return false;
   }
 
   // Check: Error - See if there was an expected prefix for the package and
@@ -957,7 +967,7 @@ bool ValidateObjCClassPrefix(const FileDescriptor* file, string* out_error) {
       return true;
     } else {
       // ...it didn't match!
-      *out_error = "protoc:0: error: Expected 'option objc_class_prefix = \"" +
+      *out_error = "error: Expected 'option objc_class_prefix = \"" +
                    package_match->second + "\";' in '" + file->name() + "'";
       if (prefix.length()) {
         *out_error += "; but found '" + prefix + "' instead";
@@ -980,11 +990,11 @@ bool ValidateObjCClassPrefix(const FileDescriptor* file, string* out_error) {
        i != expected_package_prefixes.end(); ++i) {
     if (i->second == prefix) {
       *out_error =
-          "protoc:0: error: Found 'option objc_class_prefix = \"" + prefix +
+          "error: Found 'option objc_class_prefix = \"" + prefix +
           "\";' in '" + file->name() +
           "'; that prefix is already used for 'package " + i->first +
           ";'. It can only be reused by listing it in the expected file (" +
-          expect_file_path + ").";
+          generation_options.expected_prefixes_path + ").";
       return false;  // Only report first usage of the prefix.
     }
   }
@@ -1017,7 +1027,7 @@ bool ValidateObjCClassPrefix(const FileDescriptor* file, string* out_error) {
          << "protoc:0: warning: Found unexpected 'option objc_class_prefix = \""
          << prefix << "\";' in '" << file->name() << "';"
          << " consider adding it to the expected prefixes file ("
-         << expect_file_path << ")." << endl;
+         << generation_options.expected_prefixes_path << ")." << endl;
     cerr.flush();
   }
 
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_helpers.h b/src/google/protobuf/compiler/objectivec/objectivec_helpers.h
index 85744862..5b2dd190 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_helpers.h
+++ b/src/google/protobuf/compiler/objectivec/objectivec_helpers.h
@@ -42,6 +42,12 @@ namespace protobuf {
 namespace compiler {
 namespace objectivec {
 
+// Generator options (see objectivec_generator.cc for a description of each):
+struct Options {
+  Options();
+  string expected_prefixes_path;
+};
+
 // Strips ".proto" or ".protodevel" from the end of a filename.
 string StripProto(const string& filename);
 
@@ -145,7 +151,9 @@ string BuildCommentsString(const SourceLocation& location);
 // Checks the prefix for a given file and outputs any warnings needed, if
 // there are flat out errors, then out_error is filled in and the result is
 // false.
-bool ValidateObjCClassPrefix(const FileDescriptor* file, string *out_error);
+bool ValidateObjCClassPrefix(const FileDescriptor* file,
+                             const Options& generation_options,
+                             string* out_error);
 
 // Generate decode data needed for ObjC's GPBDecodeTextFormatName() to transform
 // the input into the expected output.
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_map_field.cc b/src/google/protobuf/compiler/objectivec/objectivec_map_field.cc
index 2987f3db..2751e936 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_map_field.cc
+++ b/src/google/protobuf/compiler/objectivec/objectivec_map_field.cc
@@ -84,13 +84,14 @@ const char* MapEntryTypeName(const FieldDescriptor* descriptor, bool isKey) {
 
 }  // namespace
 
-MapFieldGenerator::MapFieldGenerator(const FieldDescriptor* descriptor)
-    : RepeatedFieldGenerator(descriptor) {
+MapFieldGenerator::MapFieldGenerator(const FieldDescriptor* descriptor,
+                                     const Options& options)
+    : RepeatedFieldGenerator(descriptor, options) {
   const FieldDescriptor* key_descriptor =
       descriptor->message_type()->FindFieldByName("key");
   const FieldDescriptor* value_descriptor =
       descriptor->message_type()->FindFieldByName("value");
-  value_field_generator_.reset(FieldGenerator::Make(value_descriptor));
+  value_field_generator_.reset(FieldGenerator::Make(value_descriptor, options));
 
   // Pull over some variables_ from the value.
   variables_["field_type"] = value_field_generator_->variable("field_type");
@@ -117,16 +118,27 @@ MapFieldGenerator::MapFieldGenerator(const FieldDescriptor* descriptor)
   variables_["fieldflags"] = BuildFlagsString(field_flags);
 
   ObjectiveCType value_objc_type = GetObjectiveCType(value_descriptor);
-  if ((GetObjectiveCType(key_descriptor) == OBJECTIVECTYPE_STRING) &&
+  const bool value_is_object_type =
       ((value_objc_type == OBJECTIVECTYPE_STRING) ||
        (value_objc_type == OBJECTIVECTYPE_DATA) ||
-       (value_objc_type == OBJECTIVECTYPE_MESSAGE))) {
+       (value_objc_type == OBJECTIVECTYPE_MESSAGE));
+  if ((GetObjectiveCType(key_descriptor) == OBJECTIVECTYPE_STRING) &&
+      value_is_object_type) {
     variables_["array_storage_type"] = "NSMutableDictionary";
+    variables_["array_property_type"] =
+        "NSMutableDictionary<NSString*, " +
+        value_field_generator_->variable("storage_type") + "*>";
   } else {
-    string base_name = MapEntryTypeName(key_descriptor, true);
-    base_name += MapEntryTypeName(value_descriptor, false);
-    base_name += "Dictionary";
-    variables_["array_storage_type"] = "GPB" + base_name;
+    string class_name("GPB");
+    class_name += MapEntryTypeName(key_descriptor, true);
+    class_name += MapEntryTypeName(value_descriptor, false);
+    class_name += "Dictionary";
+    variables_["array_storage_type"] = class_name;
+    if (value_is_object_type) {
+      variables_["array_property_type"] =
+          class_name + "<" +
+          value_field_generator_->variable("storage_type") + "*>";
+    }
   }
 }
 
@@ -138,15 +150,9 @@ void MapFieldGenerator::FinishInitialization(void) {
   // values in the map are.
   const FieldDescriptor* value_descriptor =
       descriptor_->message_type()->FindFieldByName("value");
-  ObjectiveCType value_objc_type = GetObjectiveCType(value_descriptor);
-  if ((value_objc_type == OBJECTIVECTYPE_MESSAGE) ||
-      (value_objc_type == OBJECTIVECTYPE_DATA) ||
-      (value_objc_type == OBJECTIVECTYPE_STRING) ||
-      (value_objc_type == OBJECTIVECTYPE_ENUM)) {
+  if (GetObjectiveCType(value_descriptor) == OBJECTIVECTYPE_ENUM) {
     variables_["array_comment"] =
         "// |" + variables_["name"] + "| values are |" + value_field_generator_->variable("storage_type") + "|\n";
-  } else {
-    variables_["array_comment"] = "";
   }
 }
 
@@ -157,6 +163,19 @@ void MapFieldGenerator::GenerateFieldDescriptionTypeSpecific(
   value_field_generator_->GenerateFieldDescriptionTypeSpecific(printer);
 }
 
+void MapFieldGenerator::DetermineForwardDeclarations(
+    set<string>* fwd_decls) const {
+  RepeatedFieldGenerator::DetermineForwardDeclarations(fwd_decls);
+  const FieldDescriptor* value_descriptor =
+      descriptor_->message_type()->FindFieldByName("value");
+  if (GetObjectiveCType(value_descriptor) == OBJECTIVECTYPE_MESSAGE) {
+    const string& value_storage_type =
+        value_field_generator_->variable("storage_type");
+    fwd_decls->insert("@class " + value_storage_type);
+  }
+}
+
+
 }  // namespace objectivec
 }  // namespace compiler
 }  // namespace protobuf
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_map_field.h b/src/google/protobuf/compiler/objectivec/objectivec_map_field.h
index 173541f2..7351ea05 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_map_field.h
+++ b/src/google/protobuf/compiler/objectivec/objectivec_map_field.h
@@ -41,18 +41,22 @@ namespace compiler {
 namespace objectivec {
 
 class MapFieldGenerator : public RepeatedFieldGenerator {
-  friend FieldGenerator* FieldGenerator::Make(const FieldDescriptor* field);
+  friend FieldGenerator* FieldGenerator::Make(const FieldDescriptor* field,
+                                              const Options& options);
 
  public:
   virtual void FinishInitialization(void);
   virtual void GenerateFieldDescriptionTypeSpecific(io::Printer* printer) const;
 
  protected:
-  explicit MapFieldGenerator(const FieldDescriptor* descriptor);
+  MapFieldGenerator(const FieldDescriptor* descriptor, const Options& options);
   virtual ~MapFieldGenerator();
 
+  virtual void DetermineForwardDeclarations(set<string>* fwd_decls) const;
+
  private:
   scoped_ptr<FieldGenerator> value_field_generator_;
+
   GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(MapFieldGenerator);
 };
 
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_message.cc b/src/google/protobuf/compiler/objectivec/objectivec_message.cc
index 32671d42..e0ea8bd2 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_message.cc
+++ b/src/google/protobuf/compiler/objectivec/objectivec_message.cc
@@ -174,10 +174,11 @@ const FieldDescriptor** SortFieldsByStorageSize(const Descriptor* descriptor) {
 }  // namespace
 
 MessageGenerator::MessageGenerator(const string& root_classname,
-                                   const Descriptor* descriptor)
+                                   const Descriptor* descriptor,
+                                   const Options& options)
     : root_classname_(root_classname),
       descriptor_(descriptor),
-      field_generators_(descriptor),
+      field_generators_(descriptor, options),
       class_name_(ClassName(descriptor_)) {
   for (int i = 0; i < descriptor_->extension_count(); i++) {
     extension_generators_.push_back(
@@ -196,7 +197,9 @@ MessageGenerator::MessageGenerator(const string& root_classname,
 
   for (int i = 0; i < descriptor_->nested_type_count(); i++) {
     MessageGenerator* generator =
-        new MessageGenerator(root_classname_, descriptor_->nested_type(i));
+        new MessageGenerator(root_classname_,
+                             descriptor_->nested_type(i),
+                             options);
     nested_message_generators_.push_back(generator);
   }
 }
@@ -230,11 +233,6 @@ void MessageGenerator::DetermineForwardDeclarations(set<string>* fwd_decls) {
   if (!IsMapEntryMessage(descriptor_)) {
     for (int i = 0; i < descriptor_->field_count(); i++) {
       const FieldDescriptor* fieldDescriptor = descriptor_->field(i);
-      // If it is a the field is repeated, the type will be and *Array, and we
-      // don't need any forward decl.
-      if (fieldDescriptor->is_repeated()) {
-        continue;
-      }
       field_generators_.get(fieldDescriptor)
           .DetermineForwardDeclarations(fwd_decls);
     }
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_message.h b/src/google/protobuf/compiler/objectivec/objectivec_message.h
index 06b536ff..8565e76f 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_message.h
+++ b/src/google/protobuf/compiler/objectivec/objectivec_message.h
@@ -54,7 +54,9 @@ class EnumGenerator;
 
 class MessageGenerator {
  public:
-  MessageGenerator(const string& root_classname, const Descriptor* descriptor);
+  MessageGenerator(const string& root_classname,
+                   const Descriptor* descriptor,
+                   const Options& options);
   ~MessageGenerator();
 
   void GenerateStaticVariablesInitialization(io::Printer* printer);
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_message_field.cc b/src/google/protobuf/compiler/objectivec/objectivec_message_field.cc
index f2ce4e5b..d6ccd6d1 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_message_field.cc
+++ b/src/google/protobuf/compiler/objectivec/objectivec_message_field.cc
@@ -58,8 +58,9 @@ void SetMessageVariables(const FieldDescriptor* descriptor,
 
 }  // namespace
 
-MessageFieldGenerator::MessageFieldGenerator(const FieldDescriptor* descriptor)
-    : ObjCObjFieldGenerator(descriptor) {
+MessageFieldGenerator::MessageFieldGenerator(const FieldDescriptor* descriptor,
+                                             const Options& options)
+    : ObjCObjFieldGenerator(descriptor, options) {
   SetMessageVariables(descriptor, &variables_);
 }
 
@@ -67,6 +68,7 @@ MessageFieldGenerator::~MessageFieldGenerator() {}
 
 void MessageFieldGenerator::DetermineForwardDeclarations(
     set<string>* fwd_decls) const {
+  ObjCObjFieldGenerator::DetermineForwardDeclarations(fwd_decls);
   // Class name is already in "storage_type".
   fwd_decls->insert("@class " + variable("storage_type"));
 }
@@ -82,14 +84,24 @@ bool MessageFieldGenerator::WantsHasProperty(void) const {
 }
 
 RepeatedMessageFieldGenerator::RepeatedMessageFieldGenerator(
-    const FieldDescriptor* descriptor)
-    : RepeatedFieldGenerator(descriptor) {
+    const FieldDescriptor* descriptor, const Options& options)
+    : RepeatedFieldGenerator(descriptor, options) {
   SetMessageVariables(descriptor, &variables_);
   variables_["array_storage_type"] = "NSMutableArray";
+  variables_["array_property_type"] =
+      "NSMutableArray<" + variables_["storage_type"] + "*>";
 }
 
 RepeatedMessageFieldGenerator::~RepeatedMessageFieldGenerator() {}
 
+void RepeatedMessageFieldGenerator::DetermineForwardDeclarations(
+    set<string>* fwd_decls) const {
+  RepeatedFieldGenerator::DetermineForwardDeclarations(fwd_decls);
+  // Class name is already in "storage_type".
+  fwd_decls->insert("@class " + variable("storage_type"));
+}
+
+
 }  // namespace objectivec
 }  // namespace compiler
 }  // namespace protobuf
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_message_field.h b/src/google/protobuf/compiler/objectivec/objectivec_message_field.h
index 708ea566..d2dba153 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_message_field.h
+++ b/src/google/protobuf/compiler/objectivec/objectivec_message_field.h
@@ -41,10 +41,12 @@ namespace compiler {
 namespace objectivec {
 
 class MessageFieldGenerator : public ObjCObjFieldGenerator {
-  friend FieldGenerator* FieldGenerator::Make(const FieldDescriptor* field);
+  friend FieldGenerator* FieldGenerator::Make(const FieldDescriptor* field,
+                                              const Options& options);
 
  protected:
-  explicit MessageFieldGenerator(const FieldDescriptor* descriptor);
+  MessageFieldGenerator(const FieldDescriptor* descriptor,
+                        const Options& options);
   virtual ~MessageFieldGenerator();
   virtual bool WantsHasProperty(void) const;
 
@@ -56,12 +58,17 @@ class MessageFieldGenerator : public ObjCObjFieldGenerator {
 };
 
 class RepeatedMessageFieldGenerator : public RepeatedFieldGenerator {
-  friend FieldGenerator* FieldGenerator::Make(const FieldDescriptor* field);
+  friend FieldGenerator* FieldGenerator::Make(const FieldDescriptor* field,
+                                              const Options& options);
 
  protected:
-  explicit RepeatedMessageFieldGenerator(const FieldDescriptor* descriptor);
+  RepeatedMessageFieldGenerator(const FieldDescriptor* descriptor,
+                                const Options& options);
   virtual ~RepeatedMessageFieldGenerator();
 
+ public:
+  virtual void DetermineForwardDeclarations(set<string>* fwd_decls) const;
+
  private:
   GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(RepeatedMessageFieldGenerator);
 };
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_primitive_field.cc b/src/google/protobuf/compiler/objectivec/objectivec_primitive_field.cc
index c185b66d..ea7f1b91 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_primitive_field.cc
+++ b/src/google/protobuf/compiler/objectivec/objectivec_primitive_field.cc
@@ -74,7 +74,7 @@ const char* PrimitiveTypeName(const FieldDescriptor* descriptor) {
     case OBJECTIVECTYPE_ENUM:
       return "int32_t";
     case OBJECTIVECTYPE_MESSAGE:
-      return NULL;
+      return NULL;  // Messages go through objectivec_message_field.cc|h.
   }
 
   // Some compilers report reaching end of function even though all cases of
@@ -107,7 +107,8 @@ const char* PrimitiveArrayTypeName(const FieldDescriptor* descriptor) {
     case OBJECTIVECTYPE_ENUM:
       return "Enum";
     case OBJECTIVECTYPE_MESSAGE:
-      return "";  // Want NSArray
+      // Want NSArray (but goes through objectivec_message_field.cc|h).
+      return "";
   }
 
   // Some compilers report reaching end of function even though all cases of
@@ -126,16 +127,16 @@ void SetPrimitiveVariables(const FieldDescriptor* descriptor,
 }  // namespace
 
 PrimitiveFieldGenerator::PrimitiveFieldGenerator(
-    const FieldDescriptor* descriptor)
-    : SingleFieldGenerator(descriptor) {
+    const FieldDescriptor* descriptor, const Options& options)
+    : SingleFieldGenerator(descriptor, options) {
   SetPrimitiveVariables(descriptor, &variables_);
 }
 
 PrimitiveFieldGenerator::~PrimitiveFieldGenerator() {}
 
 PrimitiveObjFieldGenerator::PrimitiveObjFieldGenerator(
-    const FieldDescriptor* descriptor)
-    : ObjCObjFieldGenerator(descriptor) {
+    const FieldDescriptor* descriptor, const Options& options)
+    : ObjCObjFieldGenerator(descriptor, options) {
   SetPrimitiveVariables(descriptor, &variables_);
   variables_["property_storage_attribute"] = "copy";
 }
@@ -143,8 +144,8 @@ PrimitiveObjFieldGenerator::PrimitiveObjFieldGenerator(
 PrimitiveObjFieldGenerator::~PrimitiveObjFieldGenerator() {}
 
 RepeatedPrimitiveFieldGenerator::RepeatedPrimitiveFieldGenerator(
-    const FieldDescriptor* descriptor)
-    : RepeatedFieldGenerator(descriptor) {
+    const FieldDescriptor* descriptor, const Options& options)
+    : RepeatedFieldGenerator(descriptor, options) {
   SetPrimitiveVariables(descriptor, &variables_);
 
   string base_name = PrimitiveArrayTypeName(descriptor);
@@ -152,19 +153,13 @@ RepeatedPrimitiveFieldGenerator::RepeatedPrimitiveFieldGenerator(
     variables_["array_storage_type"] = "GPB" + base_name + "Array";
   } else {
     variables_["array_storage_type"] = "NSMutableArray";
+    variables_["array_property_type"] =
+        "NSMutableArray<" + variables_["storage_type"] + "*>";
   }
 }
 
 RepeatedPrimitiveFieldGenerator::~RepeatedPrimitiveFieldGenerator() {}
 
-void RepeatedPrimitiveFieldGenerator::FinishInitialization(void) {
-  RepeatedFieldGenerator::FinishInitialization();
-  if (IsPrimitiveType(descriptor_)) {
-    // No comment needed for primitive types.
-    variables_["array_comment"] = "";
-  }
-}
-
 }  // namespace objectivec
 }  // namespace compiler
 }  // namespace protobuf
diff --git a/src/google/protobuf/compiler/objectivec/objectivec_primitive_field.h b/src/google/protobuf/compiler/objectivec/objectivec_primitive_field.h
index 9bb79343..87139afb 100644
--- a/src/google/protobuf/compiler/objectivec/objectivec_primitive_field.h
+++ b/src/google/protobuf/compiler/objectivec/objectivec_primitive_field.h
@@ -41,10 +41,12 @@ namespace compiler {
 namespace objectivec {
 
 class PrimitiveFieldGenerator : public SingleFieldGenerator {
-  friend FieldGenerator* FieldGenerator::Make(const FieldDescriptor* field);
+  friend FieldGenerator* FieldGenerator::Make(const FieldDescriptor* field,
+                                              const Options& options);
 
  protected:
-  explicit PrimitiveFieldGenerator(const FieldDescriptor* descriptor);
+  PrimitiveFieldGenerator(const FieldDescriptor* descriptor,
+                          const Options& options);
   virtual ~PrimitiveFieldGenerator();
 
  private:
@@ -52,10 +54,12 @@ class PrimitiveFieldGenerator : public SingleFieldGenerator {
 };
 
 class PrimitiveObjFieldGenerator : public ObjCObjFieldGenerator {
-  friend FieldGenerator* FieldGenerator::Make(const FieldDescriptor* field);
+  friend FieldGenerator* FieldGenerator::Make(const FieldDescriptor* field,
+                                              const Options& options);
 
  protected:
-  explicit PrimitiveObjFieldGenerator(const FieldDescriptor* descriptor);
+  PrimitiveObjFieldGenerator(const FieldDescriptor* descriptor,
+                             const Options& options);
   virtual ~PrimitiveObjFieldGenerator();
 
  private:
@@ -63,12 +67,13 @@ class PrimitiveObjFieldGenerator : public ObjCObjFieldGenerator {
 };
 
 class RepeatedPrimitiveFieldGenerator : public RepeatedFieldGenerator {
-  friend FieldGenerator* FieldGenerator::Make(const FieldDescriptor* field);
+  friend FieldGenerator* FieldGenerator::Make(const FieldDescriptor* field,
+                                              const Options& options);
 
  protected:
-  explicit RepeatedPrimitiveFieldGenerator(const FieldDescriptor* descriptor);
+  RepeatedPrimitiveFieldGenerator(const FieldDescriptor* descriptor,
+                                  const Options& options);
   virtual ~RepeatedPrimitiveFieldGenerator();
-  virtual void FinishInitialization(void);
 
  private:
   GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(RepeatedPrimitiveFieldGenerator);