src/google/protobuf/compiler/js/js_generator.cc

// Protocol Buffers - Google's data interchange format
// Copyright 2008 Google Inc.  All rights reserved.
// https://developers.google.com/protocol-buffers/
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//     * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (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 <google/protobuf/compiler/js/js_generator.h>

#include <assert.h>
#include <algorithm>
#include <limits>
#include <map>
#include <memory>
#ifndef _SHARED_PTR_H
#include <google/protobuf/stubs/shared_ptr.h>
#endif
#include <string>
#include <utility>
#include <vector>

#include <google/protobuf/stubs/logging.h>
#include <google/protobuf/stubs/common.h>
#include <google/protobuf/stubs/stringprintf.h>
#include <google/protobuf/io/printer.h>
#include <google/protobuf/io/zero_copy_stream.h>
#include <google/protobuf/descriptor.pb.h>
#include <google/protobuf/descriptor.h>
#include <google/protobuf/stubs/strutil.h>

namespace google {
namespace protobuf {
namespace compiler {
namespace js {

// Sorted list of JavaScript keywords. These cannot be used as names. If they
// appear, we prefix them with "pb_".
const char* kKeyword[] = {
  "abstract",
  "boolean",
  "break",
  "byte",
  "case",
  "catch",
  "char",
  "class",
  "const",
  "continue",
  "debugger",
  "default",
  "delete",
  "do",
  "double",
  "else",
  "enum",
  "export",
  "extends",
  "false",
  "final",
  "finally",
  "float",
  "for",
  "function",
  "goto",
  "if",
  "implements",
  "import",
  "in",
  "instanceof",
  "int",
  "interface",
  "long",
  "native",
  "new",
  "null",
  "package",
  "private",
  "protected",
  "public",
  "return",
  "short",
  "static",
  "super",
  "switch",
  "synchronized",
  "this",
  "throw",
  "throws",
  "transient",
  "try",
  "typeof",
  "var",
  "void",
  "volatile",
  "while",
  "with",
};

static const int kNumKeyword = sizeof(kKeyword) / sizeof(char*);

namespace {

bool IsReserved(const string& ident) {
  for (int i = 0; i < kNumKeyword; i++) {
    if (ident == kKeyword[i]) {
      return true;
    }
  }
  return false;
}

// Returns a copy of |filename| with any trailing ".protodevel" or ".proto
// suffix stripped.
string StripProto(const string& filename) {
  const char* suffix = HasSuffixString(filename, ".protodevel")
      ? ".protodevel" : ".proto";
  return StripSuffixString(filename, suffix);
}

// Returns the fully normalized JavaScript path for the given
// file descriptor's package.
string GetPath(const GeneratorOptions& options,
               const FileDescriptor* file) {
  if (!options.namespace_prefix.empty()) {
    return options.namespace_prefix;
  } else if (!file->package().empty()) {
    return "proto." + file->package();
  } else {
    return "proto";
  }
}

// Forward declare, so that GetPrefix can call this method,
// which in turn, calls GetPrefix.
string GetPath(const GeneratorOptions& options,
               const Descriptor* descriptor);

// Returns the path prefix for a message or enumeration that
// lives under the given file and containing type.
string GetPrefix(const GeneratorOptions& options,
                 const FileDescriptor* file_descriptor,
                 const Descriptor* containing_type) {
  string prefix = "";

  if (containing_type == NULL) {
    prefix = GetPath(options, file_descriptor);
  } else {
    prefix = GetPath(options, containing_type);
  }

  if (!prefix.empty()) {
    prefix += ".";
  }

  return prefix;
}


// Returns the fully normalized JavaScript path for the given
// message descriptor.
string GetPath(const GeneratorOptions& options,
               const Descriptor* descriptor) {
  return GetPrefix(
      options, descriptor->file(),
      descriptor->containing_type()) + descriptor->name();
}


// Returns the fully normalized JavaScript path for the given
// field's containing message descriptor.
string GetPath(const GeneratorOptions& options,
               const FieldDescriptor* descriptor) {
  return GetPath(options, descriptor->containing_type());
}

// Returns the fully normalized JavaScript path for the given
// enumeration descriptor.
string GetPath(const GeneratorOptions& options,
               const EnumDescriptor* enum_descriptor) {
  return GetPrefix(
      options, enum_descriptor->file(),
      enum_descriptor->containing_type()) + enum_descriptor->name();
}


// Returns the fully normalized JavaScript path for the given
// enumeration value descriptor.
string GetPath(const GeneratorOptions& options,
               const EnumValueDescriptor* value_descriptor) {
  return GetPath(
      options,
      value_descriptor->type()) + "." + value_descriptor->name();
}

// - Object field name: LOWER_UNDERSCORE -> LOWER_CAMEL, except for group fields
// (UPPER_CAMEL -> LOWER_CAMEL), with "List" (or "Map") appended if appropriate,
// and with reserved words triggering a "pb_" prefix.
// - Getters/setters: LOWER_UNDERSCORE -> UPPER_CAMEL, except for group fields
// (use the name directly), then append "List" if appropriate, then append "$"
// if resulting name is equal to a reserved word.
// - Enums: just uppercase.

// Locale-independent version of ToLower that deals only with ASCII A-Z.
char ToLowerASCII(char c) {
  if (c >= 'A' && c <= 'Z') {
    return (c - 'A') + 'a';
  } else {
    return c;
  }
}

vector<string> ParseLowerUnderscore(const string& input) {
  vector<string> words;
  string running = "";
  for (int i = 0; i < input.size(); i++) {
    if (input[i] == '_') {
      if (!running.empty()) {
        words.push_back(running);
        running.clear();
      }
    } else {
      running += ToLowerASCII(input[i]);
    }
  }
  if (!running.empty()) {
    words.push_back(running);
  }
  return words;
}

vector<string> ParseUpperCamel(const string& input) {
  vector<string> words;
  string running = "";
  for (int i = 0; i < input.size(); i++) {
    if (input[i] >= 'A' && input[i] <= 'Z' && !running.empty()) {
      words.push_back(running);
      running.clear();
    }
    running += ToLowerASCII(input[i]);
  }
  if (!running.empty()) {
    words.push_back(running);
  }
  return words;
}

string ToLowerCamel(const vector<string>& words) {
  string result;
  for (int i = 0; i < words.size(); i++) {
    string word = words[i];
    if (i == 0 && (word[0] >= 'A' && word[0] <= 'Z')) {
      word[0] = (word[0] - 'A') + 'a';
    } else if (i != 0 && (word[0] >= 'a' && word[0] <= 'z')) {
      word[0] = (word[0] - 'a') + 'A';
    }
    result += word;
  }
  return result;
}

string ToUpperCamel(const vector<string>& words) {
  string result;
  for (int i = 0; i < words.size(); i++) {
    string word = words[i];
    if (word[0] >= 'a' && word[0] <= 'z') {
      word[0] = (word[0] - 'a') + 'A';
    }
    result += word;
  }
  return result;
}

// Based on code from descriptor.cc (Thanks Kenton!)
// Uppercases the entire string, turning ValueName into
// VALUENAME.
string ToEnumCase(const string& input) {
  string result;
  result.reserve(input.size());

  for (int i = 0; i < input.size(); i++) {
    if ('a' <= input[i] && input[i] <= 'z') {
      result.push_back(input[i] - 'a' + 'A');
    } else {
      result.push_back(input[i]);
    }
  }

  return result;
}

string ToFileName(const string& input) {
  string result;
  result.reserve(input.size());

  for (int i = 0; i < input.size(); i++) {
    if ('A' <= input[i] && input[i] <= 'Z') {
      result.push_back(input[i] - 'A' + 'a');
    } else {
      result.push_back(input[i]);
    }
  }

  return result;
}

// Returns the message/response ID, if set.
string GetMessageId(const Descriptor* desc) {
  return string();
}


// Used inside Google only -- do not remove.
bool IsResponse(const Descriptor* desc) { return false; }
bool IgnoreField(const FieldDescriptor* field) { return false; }


// Does JSPB ignore this entire oneof? True only if all fields are ignored.
bool IgnoreOneof(const OneofDescriptor* oneof) {
  for (int i = 0; i < oneof->field_count(); i++) {
    if (!IgnoreField(oneof->field(i))) {
      return false;
    }
  }
  return true;
}

string JSIdent(const FieldDescriptor* field,
               bool is_upper_camel,
               bool is_map) {
  string result;
  if (field->type() == FieldDescriptor::TYPE_GROUP) {
    result = is_upper_camel ?
        ToUpperCamel(ParseUpperCamel(field->message_type()->name())) :
        ToLowerCamel(ParseUpperCamel(field->message_type()->name()));
  } else {
    result = is_upper_camel ?
        ToUpperCamel(ParseLowerUnderscore(field->name())) :
        ToLowerCamel(ParseLowerUnderscore(field->name()));
  }
  if (is_map) {
    result += "Map";
  } else if (field->is_repeated()) {
    result += "List";
  }
  return result;
}

string JSObjectFieldName(const FieldDescriptor* field) {
  string name = JSIdent(
      field,
      /* is_upper_camel = */ false,
      /* is_map = */ false);
  if (IsReserved(name)) {
    name = "pb_" + name;
  }
  return name;
}

// Returns the field name as a capitalized portion of a getter/setter method
// name, e.g. MyField for .getMyField().
string JSGetterName(const FieldDescriptor* field) {
  string name = JSIdent(field,
                        /* is_upper_camel = */ true,
                        /* is_map = */ false);
  if (name == "Extension" || name == "JsPbMessageId") {
    // Avoid conflicts with base-class names.
    name += "$";
  }
  return name;
}

string JSMapGetterName(const FieldDescriptor* field) {
  return JSIdent(field,
                 /* is_upper_camel = */ true,
                 /* is_map = */ true);
}



string JSOneofName(const OneofDescriptor* oneof) {
  return ToUpperCamel(ParseLowerUnderscore(oneof->name()));
}

// Returns the index corresponding to this field in the JSPB array (underlying
// data storage array).
string JSFieldIndex(const FieldDescriptor* field) {
  // Determine whether this field is a member of a group. Group fields are a bit
  // wonky: their "containing type" is a message type created just for the
  // group, and that type's parent type has a field with the group-message type
  // as its message type and TYPE_GROUP as its field type. For such fields, the
  // index we use is relative to the field number of the group submessage field.
  // For all other fields, we just use the field number.
  const Descriptor* containing_type = field->containing_type();
  const Descriptor* parent_type = containing_type->containing_type();
  if (parent_type != NULL) {
    for (int i = 0; i < parent_type->field_count(); i++) {
      if (parent_type->field(i)->type() == FieldDescriptor::TYPE_GROUP &&
          parent_type->field(i)->message_type() == containing_type) {
        return SimpleItoa(field->number() - parent_type->field(i)->number());
      }
    }
  }
  return SimpleItoa(field->number());
}

string JSOneofIndex(const OneofDescriptor* oneof) {
  int index = -1;
  for (int i = 0; i < oneof->containing_type()->oneof_decl_count(); i++) {
    const OneofDescriptor* o = oneof->containing_type()->oneof_decl(i);
    // If at least one field in this oneof is not JSPB-ignored, count the oneof.
    for (int j = 0; j < o->field_count(); j++) {
      const FieldDescriptor* f = o->field(j);
      if (!IgnoreField(f)) {
        index++;
        break;  // inner loop
      }
    }
    if (o == oneof) {
      break;
    }
  }
  return SimpleItoa(index);
}

// Decodes a codepoint in \x0000 -- \xFFFF. Since JS strings are UTF-16, we only
// need to handle the BMP (16-bit range) here.
uint16_t DecodeUTF8Codepoint(uint8_t* bytes, size_t* length) {
  if (*length == 0) {
    return 0;
  }
  size_t expected = 0;
  if ((*bytes & 0x80) == 0) {
    expected = 1;
  } else if ((*bytes & 0xe0) == 0xc0) {
    expected = 2;
  } else if ((*bytes & 0xf0) == 0xe0) {
    expected = 3;
  } else {
    // Too long -- don't accept.
    *length = 0;
    return 0;
  }

  if (*length < expected) {
    // Not enough bytes -- don't accept.
    *length = 0;
    return 0;
  }

  *length = expected;
  switch (expected) {
    case 1: return bytes[0];
    case 2: return ((bytes[0] & 0x1F) << 6)  |
                   ((bytes[1] & 0x3F) << 0);
    case 3: return ((bytes[0] & 0x0F) << 12) |
                   ((bytes[1] & 0x3F) << 6)  |
                   ((bytes[2] & 0x3F) << 0);
    default: return 0;
  }
}

// Escapes the contents of a string to be included within double-quotes ("") in
// JavaScript. |is_utf8| determines whether the input data (in a C++ string of
// chars) is UTF-8 encoded (in which case codepoints become JavaScript string
// characters, escaped with 16-bit hex escapes where necessary) or raw binary
// (in which case bytes become JavaScript string characters 0 -- 255).
string EscapeJSString(const string& in, bool is_utf8) {
  string result;
  size_t decoded = 0;
  for (size_t i = 0; i < in.size(); i += decoded) {
    uint16_t codepoint = 0;
    if (is_utf8) {
      // Decode the next UTF-8 codepoint.
      size_t have_bytes = in.size() - i;
      uint8_t bytes[3] = {
        static_cast<uint8_t>(in[i]),
        static_cast<uint8_t>(((i + 1) < in.size()) ? in[i + 1] : 0),
        static_cast<uint8_t>(((i + 2) < in.size()) ? in[i + 2] : 0),
      };
      codepoint = DecodeUTF8Codepoint(bytes, &have_bytes);
      if (have_bytes == 0) {
        break;
      }
      decoded = have_bytes;
    } else {
      codepoint = static_cast<uint16_t>(static_cast<uint8_t>(in[i]));
      decoded = 1;
    }

    // Next byte -- used for minimal octal escapes below.
    char next_byte = (i + decoded) < in.size() ?
        in[i + decoded] : 0;
    bool pad_octal = (next_byte >= '0' && next_byte <= '7');

    switch (codepoint) {
      case '\0': result += pad_octal ? "\\000" : "\\0";   break;
      case '\b': result += "\\\b";  break;
      case '\t': result += "\\\t";  break;
      case '\n': result += "\\\n";  break;
      case '\r': result += "\\\r";  break;
      case '\f': result += "\\\f";  break;
      case '\\': result += "\\\\";  break;
      case '"':  result += pad_octal ? "\\042" : "\\42"; break;
      case '&':  result += pad_octal ? "\\046" : "\\46"; break;
      case '\'': result += pad_octal ? "\\047" : "\\47"; break;
      case '<':  result += pad_octal ? "\\074" : "\\74"; break;
      case '=':  result += pad_octal ? "\\075" : "\\75"; break;
      case '>':  result += pad_octal ? "\\076" : "\\76"; break;
      default:
        // All other non-ASCII codepoints are escaped.
        // Original codegen uses hex for >= 0x100 and octal for others.
        if (codepoint >= 0x20 && codepoint <= 0x7e) {
          result += static_cast<char>(codepoint);
        } else {
          if (codepoint >= 0x100) {
            result += StringPrintf("\\u%04x", codepoint);
          } else {
            if (pad_octal || codepoint >= 0100) {
              result += "\\";
              result += ('0' + ((codepoint >> 6) & 07));
              result += ('0' + ((codepoint >> 3) & 07));
              result += ('0' + ((codepoint >> 0) & 07));
            } else if (codepoint >= 010) {
              result += "\\";
              result += ('0' + ((codepoint >> 3) & 07));
              result += ('0' + ((codepoint >> 0) & 07));
            } else {
              result += "\\";
              result += ('0' + ((codepoint >> 0) & 07));
            }
          }
        }
        break;
    }
  }
  return result;
}

string EscapeBase64(const string& in) {
  static const char* kAlphabet =
      "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
  string result;

  for (size_t i = 0; i < in.size(); i += 3) {
    int value = (in[i] << 16) |
        (((i + 1) < in.size()) ? (in[i + 1] << 8) : 0) |
        (((i + 2) < in.size()) ? (in[i + 2] << 0) : 0);
    result += kAlphabet[(value >> 18) & 0x3f];
    result += kAlphabet[(value >> 12) & 0x3f];
    if ((i + 1) < in.size()) {
      result += kAlphabet[(value >>  6) & 0x3f];
    } else {
      result += '=';
    }
    if ((i + 2) < in.size()) {
      result += kAlphabet[(value >>  0) & 0x3f];
    } else {
      result += '=';
    }
  }

  return result;
}

// Post-process the result of SimpleFtoa/SimpleDtoa to *exactly* match the
// original codegen's formatting (which is just .toString() on java.lang.Double
// or java.lang.Float).
string PostProcessFloat(string result) {
  // If inf, -inf or nan, replace with +Infinity, -Infinity or NaN.
  if (result == "inf") {
    return "Infinity";
  } else if (result == "-inf") {
    return "-Infinity";
  } else if (result == "nan") {
    return "NaN";
  }

  // If scientific notation (e.g., "1e10"), (i) capitalize the "e", (ii)
  // ensure that the mantissa (portion prior to the "e") has at least one
  // fractional digit (after the decimal point), and (iii) strip any unnecessary
  // leading zeroes and/or '+' signs from the exponent.
  string::size_type exp_pos = result.find('e');
  if (exp_pos != string::npos) {
    string mantissa = result.substr(0, exp_pos);
    string exponent = result.substr(exp_pos + 1);

    // Add ".0" to mantissa if no fractional part exists.
    if (mantissa.find('.') == string::npos) {
      mantissa += ".0";
    }

    // Strip the sign off the exponent and store as |exp_neg|.
    bool exp_neg = false;
    if (!exponent.empty() && exponent[0] == '+') {
      exponent = exponent.substr(1);
    } else if (!exponent.empty() && exponent[0] == '-') {
      exp_neg = true;
      exponent = exponent.substr(1);
    }

    // Strip any leading zeroes off the exponent.
    while (exponent.size() > 1 && exponent[0] == '0') {
      exponent = exponent.substr(1);
    }

    return mantissa + "E" + string(exp_neg ? "-" : "") + exponent;
  }

  // Otherwise, this is an ordinary decimal number. Append ".0" if result has no
  // decimal/fractional part in order to match output of original codegen.
  if (result.find('.') == string::npos) {
    result += ".0";
  }

  return result;
}

string FloatToString(float value) {
  string result = SimpleFtoa(value);
  return PostProcessFloat(result);
}

string DoubleToString(double value) {
  string result = SimpleDtoa(value);
  return PostProcessFloat(result);
}

string MaybeNumberString(const FieldDescriptor* field, const string& orig) {
  return orig;
}

string JSFieldDefault(const FieldDescriptor* field) {
  assert(field->has_default_value());
  switch (field->cpp_type()) {
    case FieldDescriptor::CPPTYPE_INT32:
      return MaybeNumberString(
          field, SimpleItoa(field->default_value_int32()));
    case FieldDescriptor::CPPTYPE_UINT32:
      // The original codegen is in Java, and Java protobufs store unsigned
      // integer values as signed integer values. In order to exactly match the
      // output, we need to reinterpret as base-2 signed. Ugh.
      return MaybeNumberString(
          field, SimpleItoa(static_cast<int32>(field->default_value_uint32())));
    case FieldDescriptor::CPPTYPE_INT64:
      return MaybeNumberString(
          field, SimpleItoa(field->default_value_int64()));
    case FieldDescriptor::CPPTYPE_UINT64:
      // See above note for uint32 -- reinterpreting as signed.
      return MaybeNumberString(
          field, SimpleItoa(static_cast<int64>(field->default_value_uint64())));
    case FieldDescriptor::CPPTYPE_ENUM:
      return SimpleItoa(field->default_value_enum()->number());
    case FieldDescriptor::CPPTYPE_BOOL:
      return field->default_value_bool() ? "true" : "false";
    case FieldDescriptor::CPPTYPE_FLOAT:
      return FloatToString(field->default_value_float());
    case FieldDescriptor::CPPTYPE_DOUBLE:
      return DoubleToString(field->default_value_double());
    case FieldDescriptor::CPPTYPE_STRING:
      if (field->type() == FieldDescriptor::TYPE_STRING) {
        return "\"" + EscapeJSString(field->default_value_string(), true) +
               "\"";
      } else {
        return "\"" + EscapeBase64(field->default_value_string()) +
               "\"";
      }
    case FieldDescriptor::CPPTYPE_MESSAGE:
      return "null";
  }
}

string ProtoTypeName(const GeneratorOptions& options,
                     const FieldDescriptor* field) {
  switch (field->type()) {
    case FieldDescriptor::TYPE_BOOL:
      return "bool";
    case FieldDescriptor::TYPE_INT32:
      return "int32";
    case FieldDescriptor::TYPE_UINT32:
      return "uint32";
    case FieldDescriptor::TYPE_SINT32:
      return "sint32";
    case FieldDescriptor::TYPE_FIXED32:
      return "fixed32";
    case FieldDescriptor::TYPE_SFIXED32:
      return "sfixed32";
    case FieldDescriptor::TYPE_INT64:
      return "int64";
    case FieldDescriptor::TYPE_UINT64:
      return "uint64";
    case FieldDescriptor::TYPE_SINT64:
      return "sint64";
    case FieldDescriptor::TYPE_FIXED64:
      return "fixed64";
    case FieldDescriptor::TYPE_SFIXED64:
      return "sfixed64";
    case FieldDescriptor::TYPE_FLOAT:
      return "float";
    case FieldDescriptor::TYPE_DOUBLE:
      return "double";
    case FieldDescriptor::TYPE_STRING:
      return "string";
    case FieldDescriptor::TYPE_BYTES:
      return "bytes";
    case FieldDescriptor::TYPE_GROUP:
      return GetPath(options, field->message_type());
    case FieldDescriptor::TYPE_ENUM:
      return GetPath(options, field->enum_type());
    case FieldDescriptor::TYPE_MESSAGE:
      return GetPath(options, field->message_type());
    default:
      return "";
  }
}

string JSIntegerTypeName(const FieldDescriptor* field) {
  return "number";
}

string JSTypeName(const GeneratorOptions& options,
                  const FieldDescriptor* field) {
  switch (field->cpp_type()) {
    case FieldDescriptor::CPPTYPE_BOOL:
      return "boolean";
    case FieldDescriptor::CPPTYPE_INT32:
      return JSIntegerTypeName(field);
    case FieldDescriptor::CPPTYPE_INT64:
      return JSIntegerTypeName(field);
    case FieldDescriptor::CPPTYPE_UINT32:
      return JSIntegerTypeName(field);
    case FieldDescriptor::CPPTYPE_UINT64:
      return JSIntegerTypeName(field);
    case FieldDescriptor::CPPTYPE_FLOAT:
      return "number";
    case FieldDescriptor::CPPTYPE_DOUBLE:
      return "number";
    case FieldDescriptor::CPPTYPE_STRING:
      return "string";
    case FieldDescriptor::CPPTYPE_ENUM:
      return GetPath(options, field->enum_type());
    case FieldDescriptor::CPPTYPE_MESSAGE:
      return GetPath(options, field->message_type());
    default:
      return "";
  }
}

bool HasFieldPresence(const FieldDescriptor* field);

string JSFieldTypeAnnotation(const GeneratorOptions& options,
                             const FieldDescriptor* field,
                             bool force_optional,
                             bool force_present,
                             bool singular_if_not_packed,
                             bool always_singular) {
  bool is_primitive =
      (field->cpp_type() != FieldDescriptor::CPPTYPE_ENUM &&
       field->cpp_type() != FieldDescriptor::CPPTYPE_MESSAGE);

  string jstype = JSTypeName(options, field);

  if (field->is_repeated() &&
      !always_singular &&
      (field->is_packed() || !singular_if_not_packed)) {
    if (!is_primitive) {
      jstype = "!" + jstype;
    }
    jstype = "Array.<" + jstype + ">";
    if (!force_optional) {
      jstype = "!" + jstype;
    }
  }

  if (field->is_optional() && is_primitive &&
      (!field->has_default_value() || force_optional) && !force_present) {
    jstype += "?";
  } else if (field->is_required() && !is_primitive && !force_optional) {
    jstype = "!" + jstype;
  }

  if (force_optional && HasFieldPresence(field)) {
    jstype += "|undefined";
  }
  if (force_present && jstype[0] != '!' && !is_primitive) {
    jstype = "!" + jstype;
  }

  return jstype;
}

string JSBinaryReaderMethodType(const FieldDescriptor* field) {
  string name = field->type_name();
  if (name[0] >= 'a' && name[0] <= 'z') {
    name[0] = (name[0] - 'a') + 'A';
  }

  return name;
}

string JSBinaryReadWriteMethodName(const FieldDescriptor* field,
                                   bool is_writer) {
  string name = JSBinaryReaderMethodType(field);
  if (is_writer && field->type() == FieldDescriptor::TYPE_BYTES) {
    // Override for `bytes` fields: treat string as raw bytes, not base64.
    name = "BytesRawString";
  }
  if (field->is_packed()) {
    name = "Packed" + name;
  } else if (is_writer && field->is_repeated()) {
    name = "Repeated" + name;
  }
  return name;
}

string JSBinaryReaderMethodName(const FieldDescriptor* field) {
  return "read" + JSBinaryReadWriteMethodName(field, /* is_writer = */ false);
}

string JSBinaryWriterMethodName(const FieldDescriptor* field) {
  return "write" + JSBinaryReadWriteMethodName(field, /* is_writer = */ true);
}

string JSReturnClause(const FieldDescriptor* desc) {
  return "";
}

string JSReturnDoc(const GeneratorOptions& options,
                   const FieldDescriptor* desc) {
  return "";
}

bool HasRepeatedFields(const Descriptor* desc) {
  for (int i = 0; i < desc->field_count(); i++) {
    if (desc->field(i)->is_repeated()) {
      return true;
    }
  }
  return false;
}

static const char* kRepeatedFieldArrayName = ".repeatedFields_";

string RepeatedFieldsArrayName(const GeneratorOptions& options,
                               const Descriptor* desc) {
  return HasRepeatedFields(desc) ?
      (GetPath(options, desc) + kRepeatedFieldArrayName) : "null";
}

bool HasOneofFields(const Descriptor* desc) {
  for (int i = 0; i < desc->field_count(); i++) {
    if (desc->field(i)->containing_oneof()) {
      return true;
    }
  }
  return false;
}

static const char* kOneofGroupArrayName = ".oneofGroups_";

string OneofFieldsArrayName(const GeneratorOptions& options,
                            const Descriptor* desc) {
  return HasOneofFields(desc) ?
      (GetPath(options, desc) + kOneofGroupArrayName) : "null";
}

string RepeatedFieldNumberList(const Descriptor* desc) {
  std::vector<string> numbers;
  for (int i = 0; i < desc->field_count(); i++) {
    if (desc->field(i)->is_repeated()) {
      numbers.push_back(JSFieldIndex(desc->field(i)));
    }
  }
  return "[" + Join(numbers, ",") + "]";
}

string OneofGroupList(const Descriptor* desc) {
  // List of arrays (one per oneof), each of which is a list of field indices
  std::vector<string> oneof_entries;
  for (int i = 0; i < desc->oneof_decl_count(); i++) {
    const OneofDescriptor* oneof = desc->oneof_decl(i);
    if (IgnoreOneof(oneof)) {
      continue;
    }

    std::vector<string> oneof_fields;
    for (int j = 0; j < oneof->field_count(); j++) {
      if (IgnoreField(oneof->field(j))) {
        continue;
      }
      oneof_fields.push_back(JSFieldIndex(oneof->field(j)));
    }
    oneof_entries.push_back("[" + Join(oneof_fields, ",") + "]");
  }
  return "[" + Join(oneof_entries, ",") + "]";
}

string JSOneofArray(const GeneratorOptions& options,
                    const FieldDescriptor* field) {
  return OneofFieldsArrayName(options, field->containing_type()) + "[" +
      JSOneofIndex(field->containing_oneof()) + "]";
}

string RelativeTypeName(const FieldDescriptor* field) {
  assert(field->cpp_type() == FieldDescriptor::CPPTYPE_ENUM ||
         field->cpp_type() == FieldDescriptor::CPPTYPE_MESSAGE);
  // For a field with an enum or message type, compute a name relative to the
  // path name of the message type containing this field.
  string package = field->file()->package();
  string containing_type = field->containing_type()->full_name() + ".";
  string type = (field->cpp_type() == FieldDescriptor::CPPTYPE_ENUM) ?
      field->enum_type()->full_name() : field->message_type()->full_name();

  // |prefix| is advanced as we find separators '.' past the common package
  // prefix that yield common prefixes in the containing type's name and this
  // type's name.
  int prefix = 0;
  for (int i = 0; i < type.size() && i < containing_type.size(); i++) {
    if (type[i] != containing_type[i]) {
      break;
    }
    if (type[i] == '.' && i >= package.size()) {
      prefix = i + 1;
    }
  }

  return type.substr(prefix);
}

string JSExtensionsObjectName(const GeneratorOptions& options,
                              const Descriptor* desc) {
  if (desc->full_name() == "google.protobuf.bridge.MessageSet") {
    return "jspb.Message.messageSetExtensions";
  } else {
    return GetPath(options, desc) + ".extensions";
  }
}

string FieldDefinition(const GeneratorOptions& options,
                       const FieldDescriptor* field) {
  string qualifier = field->is_repeated() ? "repeated" :
      (field->is_optional() ? "optional" : "required");
  string type, name;
  if (field->type() == FieldDescriptor::TYPE_ENUM ||
      field->type() == FieldDescriptor::TYPE_MESSAGE) {
    type = RelativeTypeName(field);
    name = field->name();
  } else if (field->type() == FieldDescriptor::TYPE_GROUP) {
    type = "group";
    name = field->message_type()->name();
  } else {
    type = ProtoTypeName(options, field);
    name = field->name();
  }
  return StringPrintf("%s %s %s = %d;",
                      qualifier.c_str(),
                      type.c_str(),
                      name.c_str(),
                      field->number());
}

string FieldComments(const FieldDescriptor* field) {
  string comments;
  if (field->cpp_type() == FieldDescriptor::CPPTYPE_BOOL) {
    comments +=
        " * Note that Boolean fields may be set to 0/1 when serialized from "
        "a Java server.\n"
        " * You should avoid comparisons like {@code val === true/false} in "
        "those cases.\n";
  }
  if (field->is_repeated()) {
    comments +=
        " * If you change this array by adding, removing or replacing "
        "elements, or if you\n"
        " * replace the array itself, then you must call the setter to "
        "update it.\n";
  }
  return comments;
}

bool ShouldGenerateExtension(const FieldDescriptor* field) {
  return
      field->is_extension() &&
      !IgnoreField(field);
}

bool HasExtensions(const Descriptor* desc) {
  if (desc->extension_count() > 0) {
    return true;
  }
  for (int i = 0; i < desc->nested_type_count(); i++) {
    if (HasExtensions(desc->nested_type(i))) {
      return true;
    }
  }
  return false;
}

bool HasExtensions(const FileDescriptor* file) {
  for (int i = 0; i < file->extension_count(); i++) {
    if (ShouldGenerateExtension(file->extension(i))) {
      return true;
    }
  }
  for (int i = 0; i < file->message_type_count(); i++) {
    if (HasExtensions(file->message_type(i))) {
      return true;
    }
  }
  return false;
}

bool IsExtendable(const Descriptor* desc) {
  return desc->extension_range_count() > 0;
}

// Returns the max index in the underlying data storage array beyond which the
// extension object is used.
string GetPivot(const Descriptor* desc) {
  static const int kDefaultPivot = (1 << 29);  // max field number (29 bits)

  // Find the max field number
  int max_field_number = 0;
  for (int i = 0; i < desc->field_count(); i++) {
    if (!IgnoreField(desc->field(i)) &&
        desc->field(i)->number() > max_field_number) {
      max_field_number = desc->field(i)->number();
    }
  }

  int pivot = -1;
  if (IsExtendable(desc)) {
    pivot = ((max_field_number + 1) < kDefaultPivot) ?
        (max_field_number + 1) : kDefaultPivot;
  }

  return SimpleItoa(pivot);
}

// Returns true for fields that represent "null" as distinct from the default
// value. See https://go/proto3#heading=h.kozewqqcqhuz for more information.
bool HasFieldPresence(const FieldDescriptor* field) {
  return
      (field->cpp_type() == FieldDescriptor::CPPTYPE_MESSAGE) ||
      (field->containing_oneof() != NULL) ||
      (field->file()->syntax() != FileDescriptor::SYNTAX_PROTO3);
}

// For proto3 fields without presence, returns a string representing the default
// value in JavaScript. See https://go/proto3#heading=h.kozewqqcqhuz for more
// information.
string Proto3PrimitiveFieldDefault(const FieldDescriptor* field) {
  switch (field->cpp_type()) {
    case FieldDescriptor::CPPTYPE_INT32:
    case FieldDescriptor::CPPTYPE_INT64:
    case FieldDescriptor::CPPTYPE_UINT32:
    case FieldDescriptor::CPPTYPE_UINT64: {
      return "0";
    }

    case FieldDescriptor::CPPTYPE_ENUM:
    case FieldDescriptor::CPPTYPE_FLOAT:
    case FieldDescriptor::CPPTYPE_DOUBLE:
      return "0";

    case FieldDescriptor::CPPTYPE_BOOL:
      return "false";

    case FieldDescriptor::CPPTYPE_STRING:
      return "\"\"";

    default:
      // BYTES and MESSAGE are handled separately.
      assert(false);
      return "";
  }
}

}  // anonymous namespace

void Generator::GenerateHeader(const GeneratorOptions& options,
                               io::Printer* printer) const {
  printer->Print("/**\n"
                 " * @fileoverview\n"
                 " * @enhanceable\n"
                 " * @public\n"
                 " */\n"
                 "// GENERATED CODE -- DO NOT EDIT!\n"
                 "\n");
}

void Generator::FindProvides(const GeneratorOptions& options,
                             io::Printer* printer,
                             const vector<const FileDescriptor*>& files,
                             std::set<string>* provided) const {
  for (int i = 0; i < files.size(); i++) {
    for (int j = 0; j < files[i]->message_type_count(); j++) {
      FindProvidesForMessage(options, printer, files[i]->message_type(j),
                                 provided);
    }
    for (int j = 0; j < files[i]->enum_type_count(); j++) {
      FindProvidesForEnum(options, printer, files[i]->enum_type(j),
                              provided);
    }
  }

  printer->Print("\n");
}

void Generator::FindProvidesForMessage(
    const GeneratorOptions& options,
    io::Printer* printer,
    const Descriptor* desc,
    std::set<string>* provided) const {
  string name = GetPath(options, desc);
  provided->insert(name);

  for (int i = 0; i < desc->enum_type_count(); i++) {
    FindProvidesForEnum(options, printer, desc->enum_type(i),
                        provided);
  }
  for (int i = 0; i < desc->nested_type_count(); i++) {
    FindProvidesForMessage(options, printer, desc->nested_type(i),
                           provided);
  }
}

void Generator::FindProvidesForEnum(const GeneratorOptions& options,
                                    io::Printer* printer,
                                    const EnumDescriptor* enumdesc,
                                    std::set<string>* provided) const {
  string name = GetPath(options, enumdesc);
  provided->insert(name);
}

void Generator::FindProvidesForFields(
    const GeneratorOptions& options,
    io::Printer* printer,
    const vector<const FieldDescriptor*>& fields,
    std::set<string>* provided) const {
  for (int i = 0; i < fields.size(); i++) {
    const FieldDescriptor* field = fields[i];

    if (IgnoreField(field)) {
      continue;
    }

    string name =
        GetPath(options, field->file()) + "." + JSObjectFieldName(field);
    provided->insert(name);
  }
}

void Generator::GenerateProvides(const GeneratorOptions& options,
                                 io::Printer* printer,
                                 std::set<string>* provided) const {
  for (std::set<string>::iterator it = provided->begin();
       it != provided->end(); ++it) {
    printer->Print("goog.provide('$name$');\n",
                   "name", *it);
  }
}

void Generator::GenerateRequires(const GeneratorOptions& options,
                                 io::Printer* printer,
                                 const Descriptor* desc,
                                 std::set<string>* provided) const {
  std::set<string> required;
  std::set<string> forwards;
  bool have_message = false;
  FindRequiresForMessage(options, desc,
                         &required, &forwards, &have_message);

  GenerateRequiresImpl(options, printer, &required, &forwards, provided,
                       /* require_jspb = */ have_message,
                       /* require_extension = */ HasExtensions(desc));
}

void Generator::GenerateRequires(const GeneratorOptions& options,
                                 io::Printer* printer,
                                 const vector<const FileDescriptor*>& files,
                                 std::set<string>* provided) const {
  std::set<string> required;
  std::set<string> forwards;
  bool have_extensions = false;
  bool have_message = false;

  for (int i = 0; i < files.size(); i++) {
    for (int j = 0; j < files[i]->message_type_count(); j++) {
      FindRequiresForMessage(options,
                             files[i]->message_type(j),
                             &required, &forwards, &have_message);
    }
    if (!have_extensions && HasExtensions(files[i])) {
      have_extensions = true;
    }

    for (int j = 0; j < files[i]->extension_count(); j++) {
      const FieldDescriptor* extension = files[i]->extension(j);
      if (IgnoreField(extension)) {
        continue;
      }
      if (extension->containing_type()->full_name() !=
          "google.protobuf.bridge.MessageSet") {
        required.insert(GetPath(options, extension->containing_type()));
      }
      FindRequiresForField(options, extension, &required, &forwards);
      have_extensions = true;
    }
  }

  GenerateRequiresImpl(options, printer, &required, &forwards, provided,
                       /* require_jspb = */ have_message,
                       /* require_extension = */ have_extensions);
}

void Generator::GenerateRequires(const GeneratorOptions& options,
                                 io::Printer* printer,
                                 const vector<const FieldDescriptor*>& fields,
                                 std::set<string>* provided) const {
  std::set<string> required;
  std::set<string> forwards;
  for (int i = 0; i < fields.size(); i++) {
    const FieldDescriptor* field = fields[i];
    if (IgnoreField(field)) {
      continue;
    }
    FindRequiresForExtension(options, field, &required, &forwards);
  }

  GenerateRequiresImpl(options, printer, &required, &forwards, provided,
                       /* require_jspb = */ false,
                       /* require_extension = */ fields.size() > 0);
}

void Generator::GenerateRequiresImpl(const GeneratorOptions& options,
                                     io::Printer* printer,
                                     std::set<string>* required,
                                     std::set<string>* forwards,
                                     std::set<string>* provided,
                                     bool require_jspb,
                                     bool require_extension) const {
  if (require_jspb) {
    printer->Print(
        "goog.require('jspb.Message');\n");
    if (options.binary) {
      printer->Print(
          "goog.require('jspb.BinaryReader');\n"
          "goog.require('jspb.BinaryWriter');\n");
    }
  }
  if (require_extension) {
    printer->Print(
        "goog.require('jspb.ExtensionFieldInfo');\n");
  }

  std::set<string>::iterator it;
  for (it = required->begin(); it != required->end(); ++it) {
    if (provided->find(*it) != provided->end()) {
      continue;
    }
    printer->Print("goog.require('$name$');\n",
                   "name", *it);
  }

  printer->Print("\n");

  for (it = forwards->begin(); it != forwards->end(); ++it) {
    if (provided->find(*it) != provided->end()) {
      continue;
    }
    printer->Print("goog.forwardDeclare('$name$');\n",
                   "name", *it);
  }
}

bool NamespaceOnly(const Descriptor* desc) {
  return false;
}

void Generator::FindRequiresForMessage(
    const GeneratorOptions& options,
    const Descriptor* desc,
    std::set<string>* required,
    std::set<string>* forwards,
    bool* have_message) const {


  if (!NamespaceOnly(desc)) {
    *have_message = true;
    for (int i = 0; i < desc->field_count(); i++) {
      const FieldDescriptor* field = desc->field(i);
      if (IgnoreField(field)) {
        continue;
      }
      FindRequiresForField(options, field, required, forwards);
    }
  }

  for (int i = 0; i < desc->extension_count(); i++) {
    const FieldDescriptor* field = desc->extension(i);
    if (IgnoreField(field)) {
      continue;
    }
    FindRequiresForExtension(options, field, required, forwards);
  }

  for (int i = 0; i < desc->nested_type_count(); i++) {
    FindRequiresForMessage(options, desc->nested_type(i), required, forwards,
                           have_message);
  }
}

void Generator::FindRequiresForField(const GeneratorOptions& options,
                                     const FieldDescriptor* field,
                                     std::set<string>* required,
                                     std::set<string>* forwards) const {
    if (field->cpp_type() == FieldDescriptor::CPPTYPE_ENUM &&
        // N.B.: file-level extensions with enum type do *not* create
        // dependencies, as per original codegen.
        !(field->is_extension() && field->extension_scope() == NULL)) {
      if (options.add_require_for_enums) {
        required->insert(GetPath(options, field->enum_type()));
      } else {
        forwards->insert(GetPath(options, field->enum_type()));
      }
    } else if (field->cpp_type() == FieldDescriptor::CPPTYPE_MESSAGE) {
      required->insert(GetPath(options, field->message_type()));
    }
}

void Generator::FindRequiresForExtension(const GeneratorOptions& options,
                                         const FieldDescriptor* field,
                                         std::set<string>* required,
                                         std::set<string>* forwards) const {
    if (field->containing_type()->full_name() != "google.protobuf.bridge.MessageSet") {
      required->insert(GetPath(options, field->containing_type()));
    }
    FindRequiresForField(options, field, required, forwards);
}

void Generator::GenerateTestOnly(const GeneratorOptions& options,
                                 io::Printer* printer) const {
  if (options.testonly) {
    printer->Print("goog.setTestOnly();\n\n");
  }
  printer->Print("\n");
}

void Generator::GenerateClassesAndEnums(const GeneratorOptions& options,
                                        io::Printer* printer,
                                        const FileDescriptor* file) const {
  for (int i = 0; i < file->message_type_count(); i++) {
    GenerateClass(options, printer, file->message_type(i));
  }
  for (int i = 0; i < file->enum_type_count(); i++) {
    GenerateEnum(options, printer, file->enum_type(i));
  }
}

void Generator::GenerateClass(const GeneratorOptions& options,
                              io::Printer* printer,
                              const Descriptor* desc) const {
  if (!NamespaceOnly(desc)) {
    printer->Print("\n");
    GenerateClassConstructor(options, printer, desc);
    GenerateClassFieldInfo(options, printer, desc);


    GenerateClassToObject(options, printer, desc);
    if (options.binary) {
      // These must come *before* the extension-field info generation in
      // GenerateClassRegistration so that references to the binary
      // serialization/deserialization functions may be placed in the extension
      // objects.
      GenerateClassDeserializeBinary(options, printer, desc);
      GenerateClassSerializeBinary(options, printer, desc);
    }
    GenerateClassClone(options, printer, desc);
    GenerateClassRegistration(options, printer, desc);
    GenerateClassFields(options, printer, desc);
    if (IsExtendable(desc) && desc->full_name() != "google.protobuf.bridge.MessageSet") {
      GenerateClassExtensionFieldInfo(options, printer, desc);
    }
  }

  // Recurse on nested types.
  for (int i = 0; i < desc->enum_type_count(); i++) {
    GenerateEnum(options, printer, desc->enum_type(i));
  }
  for (int i = 0; i < desc->nested_type_count(); i++) {
    GenerateClass(options, printer, desc->nested_type(i));
  }
}

void Generator::GenerateClassConstructor(const GeneratorOptions& options,
                                         io::Printer* printer,
                                         const Descriptor* desc) const {
  printer->Print(
      "/**\n"
      " * Generated by JsPbCodeGenerator.\n"
      " * @param {Array=} opt_data Optional initial data array, typically "
      "from a\n"
      " * server response, or constructed directly in Javascript. The array "
      "is used\n"
      " * in place and becomes part of the constructed object. It is not "
      "cloned.\n"
      " * If no data is provided, the constructed object will be empty, but "
      "still\n"
      " * valid.\n"
      " * @extends {jspb.Message}\n"
      " * @constructor\n"
      " */\n"
      "$classname$ = function(opt_data) {\n",
      "classname", GetPath(options, desc));
  string message_id = GetMessageId(desc);
  printer->Print(
      "  jspb.Message.initialize(this, opt_data, $messageId$, $pivot$, "
      "$rptfields$, $oneoffields$);\n",
      "messageId", !message_id.empty() ?
                   ("'" + message_id + "'") :
                   (IsResponse(desc) ? "''" : "0"),
      "pivot", GetPivot(desc),
      "rptfields", RepeatedFieldsArrayName(options, desc),
      "oneoffields", OneofFieldsArrayName(options, desc));
  printer->Print(
      "};\n"
      "goog.inherits($classname$, jspb.Message);\n"
      "if (goog.DEBUG && !COMPILED) {\n"
      "  $classname$.displayName = '$classname$';\n"
      "}\n",
      "classname", GetPath(options, desc));
}

void Generator::GenerateClassFieldInfo(const GeneratorOptions& options,
                                       io::Printer* printer,
                                       const Descriptor* desc) const {
  if (HasRepeatedFields(desc)) {
    printer->Print(
        "/**\n"
        " * List of repeated fields within this message type.\n"
        " * @private {!Array<number>}\n"
        " * @const\n"
        " */\n"
        "$classname$$rptfieldarray$ = $rptfields$;\n"
        "\n",
        "classname", GetPath(options, desc),
        "rptfieldarray", kRepeatedFieldArrayName,
        "rptfields", RepeatedFieldNumberList(desc));
  }

  if (HasOneofFields(desc)) {
    printer->Print(
        "/**\n"
        " * Oneof group definitions for this message. Each group defines the "
        "field\n"
        " * numbers belonging to that group. When of these fields' value is "
        "set, all\n"
        " * other fields in the group are cleared. During deserialization, if "
        "multiple\n"
        " * fields are encountered for a group, only the last value seen will "
        "be kept.\n"
        " * @private {!Array<!Array<number>>}\n"
        " * @const\n"
        " */\n"
        "$classname$$oneofgrouparray$ = $oneofgroups$;\n"
        "\n",
        "classname", GetPath(options, desc),
        "oneofgrouparray", kOneofGroupArrayName,
        "oneofgroups", OneofGroupList(desc));

    for (int i = 0; i < desc->oneof_decl_count(); i++) {
      if (IgnoreOneof(desc->oneof_decl(i))) {
        continue;
      }
      GenerateOneofCaseDefinition(options, printer, desc->oneof_decl(i));
    }
  }
}

void Generator::GenerateClassXid(const GeneratorOptions& options,
                                 io::Printer* printer,
                                 const Descriptor* desc) const {
  printer->Print(
      "\n"
      "\n"
      "$class$.prototype.messageXid = xid('$class$');\n",
      "class", GetPath(options, desc));
}

void Generator::GenerateOneofCaseDefinition(
    const GeneratorOptions& options,
    io::Printer* printer,
    const OneofDescriptor* oneof) const {
  printer->Print(
      "/**\n"
      " * @enum {number}\n"
      " */\n"
      "$classname$.$oneof$Case = {\n"
      "  $upcase$_NOT_SET: 0",
      "classname", GetPath(options, oneof->containing_type()),
      "oneof", JSOneofName(oneof),
      "upcase", ToEnumCase(oneof->name()));

  for (int i = 0; i < oneof->field_count(); i++) {
    if (IgnoreField(oneof->field(i))) {
      continue;
    }

    printer->Print(
        ",\n"
        "  $upcase$: $number$",
        "upcase", ToEnumCase(oneof->field(i)->name()),
        "number", JSFieldIndex(oneof->field(i)));
  }

  printer->Print(
      "\n"
      "};\n"
      "\n"
      "/**\n"
      " * @return {$class$.$oneof$Case}\n"
      " */\n"
      "$class$.prototype.get$oneof$Case = function() {\n"
      "  return /** @type {$class$.$oneof$Case} */(jspb.Message."
      "computeOneofCase(this, $class$.oneofGroups_[$oneofindex$]));\n"
      "};\n"
      "\n",
      "class", GetPath(options, oneof->containing_type()),
      "oneof", JSOneofName(oneof),
      "oneofindex", JSOneofIndex(oneof));
}

void Generator::GenerateClassToObject(const GeneratorOptions& options,
                                      io::Printer* printer,
                                      const Descriptor* desc) const {
  printer->Print(
      "\n"
      "\n"
      "if (jspb.Message.GENERATE_TO_OBJECT) {\n"
      "/**\n"
      " * Creates an object representation of this proto suitable for use in "
      "Soy templates.\n"
      " * Field names that are reserved in JavaScript and will be renamed to "
      "pb_name.\n"
      " * To access a reserved field use, foo.pb_<name>, eg, foo.pb_default.\n"
      " * For the list of reserved names please see:\n"
      " *     com.google.apps.jspb.JsClassTemplate.JS_RESERVED_WORDS.\n"
      " * @param {boolean=} opt_includeInstance Whether to include the JSPB "
      "instance\n"
      " *     for transitional soy proto support: http://goto/soy-param-"
      "migration\n"
      " * @return {!Object}\n"
      " */\n"
      "$classname$.prototype.toObject = function(opt_includeInstance) {\n"
      "  return $classname$.toObject(opt_includeInstance, this);\n"
      "};\n"
      "\n"
      "\n"
      "/**\n"
      " * Static version of the {@see toObject} method.\n"
      " * @param {boolean|undefined} includeInstance Whether to include the "
      "JSPB\n"
      " *     instance for transitional soy proto support:\n"
      " *     http://goto/soy-param-migration\n"
      " * @param {!$classname$} msg The msg instance to transform.\n"
      " * @return {!Object}\n"
      " */\n"
      "$classname$.toObject = function(includeInstance, msg) {\n"
      "  var f, obj = {",
      "classname", GetPath(options, desc));

  bool first = true;
  for (int i = 0; i < desc->field_count(); i++) {
    const FieldDescriptor* field = desc->field(i);
    if (IgnoreField(field)) {
      continue;
    }

    if (!first) {
      printer->Print(",\n    ");
    } else {
      printer->Print("\n    ");
      first = false;
    }

    GenerateClassFieldToObject(options, printer, field);
  }

  if (!first) {
    printer->Print("\n  };\n\n");
  } else {
    printer->Print("\n\n  };\n\n");
  }

  if (IsExtendable(desc)) {
    printer->Print(
        "  jspb.Message.toObjectExtension(/** @type {!jspb.Message} */ (msg), "
        "obj,\n"
        "      $extObject$, $class$.prototype.getExtension,\n"
        "      includeInstance);\n",
        "extObject", JSExtensionsObjectName(options, desc),
        "class", GetPath(options, desc));
  }

  printer->Print(
      "  if (includeInstance) {\n"
      "    obj.$$jspbMessageInstance = msg\n"
      "  }\n"
      "  return obj;\n"
      "};\n"
      "}\n"
      "\n"
      "\n",
      "classname", GetPath(options, desc));
}

void Generator::GenerateClassFieldToObject(const GeneratorOptions& options,
                                           io::Printer* printer,
                                           const FieldDescriptor* field) const {
  printer->Print("$fieldname$: ",
                 "fieldname", JSObjectFieldName(field));

  if (field->cpp_type() == FieldDescriptor::CPPTYPE_MESSAGE) {
    // Message field.
    if (field->is_repeated()) {
      {
        printer->Print("jspb.Message.toObjectList(msg.get$getter$(),\n"
                       "    $type$.toObject, includeInstance)",
                       "getter", JSGetterName(field),
                       "type", GetPath(options, field->message_type()));
      }
    } else {
      printer->Print("(f = msg.get$getter$()) && "
                     "$type$.toObject(includeInstance, f)",
                     "getter", JSGetterName(field),
                     "type", GetPath(options, field->message_type()));
    }
  } else {
    // Simple field (singular or repeated).
    if (!HasFieldPresence(field) && !field->is_repeated()) {
      // Delegate to the generated get<field>() method in order not to duplicate
      // the proto3-field-default-value logic here.
      printer->Print("msg.get$getter$()",
                     "getter", JSGetterName(field));
    } else {
      if (field->has_default_value()) {
        printer->Print("jspb.Message.getField(msg, $index$) != null ? "
                       "jspb.Message.getField(msg, $index$) : $defaultValue$",
                       "index", JSFieldIndex(field),
                       "defaultValue", JSFieldDefault(field));
      } else {
        printer->Print("jspb.Message.getField(msg, $index$)",
                       "index", JSFieldIndex(field));
      }
    }
  }
}

void Generator::GenerateClassFromObject(const GeneratorOptions& options,
                                        io::Printer* printer,
                                        const Descriptor* desc) const {
  printer->Print(
      "if (jspb.Message.GENERATE_FROM_OBJECT) {\n"
      "/**\n"
      " * Loads data from an object into a new instance of this proto.\n"
      " * @param {!Object} obj The object representation of this proto to\n"
      " *     load the data from.\n"
      " * @return {!$classname$}\n"
      " */\n"
      "$classname$.fromObject = function(obj) {\n"
      "  var f, msg = new $classname$();\n",
      "classname", GetPath(options, desc));

  for (int i = 0; i < desc->field_count(); i++) {
    const FieldDescriptor* field = desc->field(i);
    GenerateClassFieldFromObject(options, printer, field);
  }

  printer->Print(
      "  return msg;\n"
      "};\n"
      "}\n");
}

void Generator::GenerateClassFieldFromObject(
    const GeneratorOptions& options,
    io::Printer* printer,
    const FieldDescriptor* field) const {
  if (field->cpp_type() == FieldDescriptor::CPPTYPE_MESSAGE) {
    // Message field (singular or repeated)
    if (field->is_repeated()) {
      {
        printer->Print(
            "  goog.isDef(obj.$name$) && "
            "jspb.Message.setRepeatedWrapperField(\n"
            "      msg, $index$, goog.array.map(obj.$name$, function(i) {\n"
            "        return $fieldclass$.fromObject(i);\n"
            "      }));\n",
            "name", JSObjectFieldName(field),
            "index", JSFieldIndex(field),
            "fieldclass", GetPath(options, field->message_type()));
      }
    } else {
      printer->Print(
          "  goog.isDef(obj.$name$) && jspb.Message.setWrapperField(\n"
          "      msg, $index$, $fieldclass$.fromObject(obj.$name$));\n",
          "name", JSObjectFieldName(field),
          "index", JSFieldIndex(field),
          "fieldclass", GetPath(options, field->message_type()));
    }
  } else {
    // Simple (primitive) field.
    printer->Print(
        "  goog.isDef(obj.$name$) && jspb.Message.setField(msg, $index$, "
        "obj.$name$);\n",
        "name", JSObjectFieldName(field),
        "index", JSFieldIndex(field));
  }
}

void Generator::GenerateClassClone(const GeneratorOptions& options,
                                   io::Printer* printer,
                                   const Descriptor* desc) const {
  printer->Print(
      "/**\n"
      " * Creates a deep clone of this proto. No data is shared with the "
      "original.\n"
      " * @return {!$name$} The clone.\n"
      " */\n"
      "$name$.prototype.cloneMessage = function() {\n"
      "  return /** @type {!$name$} */ (jspb.Message.cloneMessage(this));\n"
      "};\n\n\n",
      "name", GetPath(options, desc));
}

void Generator::GenerateClassRegistration(const GeneratorOptions& options,
                                          io::Printer* printer,
                                          const Descriptor* desc) const {
  // Register any extensions defined inside this message type.
  for (int i = 0; i < desc->extension_count(); i++) {
    const FieldDescriptor* extension = desc->extension(i);
    if (ShouldGenerateExtension(extension)) {
      GenerateExtension(options, printer, extension);
    }
  }

}

void Generator::GenerateClassFields(const GeneratorOptions& options,
                                    io::Printer* printer,
                                    const Descriptor* desc) const {
  for (int i = 0; i < desc->field_count(); i++) {
    if (!IgnoreField(desc->field(i))) {
      GenerateClassField(options, printer, desc->field(i));
    }
  }
}

void Generator::GenerateClassField(const GeneratorOptions& options,
                                   io::Printer* printer,
                                   const FieldDescriptor* field) const {
  if (field->cpp_type() == FieldDescriptor::CPPTYPE_MESSAGE) {
    printer->Print(
        "/**\n"
        " * $fielddef$\n"
        "$comment$"
        " * @return {$type$}\n"
        " */\n",
        "fielddef", FieldDefinition(options, field),
        "comment", FieldComments(field),
        "type", JSFieldTypeAnnotation(options, field,
                                      /* force_optional = */ false,
                                      /* force_present = */ false,
                                      /* singular_if_not_packed = */ false,
                                      /* always_singular = */ false));
    printer->Print(
        "$class$.prototype.get$name$ = function() {\n"
        "  return /** @type{$type$} */ (\n"
        "    jspb.Message.get$rpt$WrapperField(this, $wrapperclass$, "
        "$index$$required$));\n"
        "};\n"
        "\n"
        "\n",
        "class", GetPath(options, field->containing_type()),
        "name", JSGetterName(field),
        "type", JSFieldTypeAnnotation(options, field,
                                      /* force_optional = */ false,
                                      /* force_present = */ false,
                                      /* singular_if_not_packed = */ false,
                                      /* always_singular = */ false),
        "rpt", (field->is_repeated() ? "Repeated" : ""),
        "index", JSFieldIndex(field),
        "wrapperclass", GetPath(options, field->message_type()),
        "required", (field->label() == FieldDescriptor::LABEL_REQUIRED ?
                     ", 1" : ""));
    printer->Print(
        "/** @param {$optionaltype$} value $returndoc$ */\n"
        "$class$.prototype.set$name$ = function(value) {\n"
        "  jspb.Message.set$oneoftag$$repeatedtag$WrapperField(",
        "optionaltype",
        JSFieldTypeAnnotation(options, field,
                              /* force_optional = */ true,
                              /* force_present = */ false,
                              /* singular_if_not_packed = */ false,
                              /* always_singular = */ false),
        "returndoc", JSReturnDoc(options, field),
        "class", GetPath(options, field->containing_type()),
        "name", JSGetterName(field),
        "oneoftag", (field->containing_oneof() ? "Oneof" : ""),
        "repeatedtag", (field->is_repeated() ? "Repeated" : ""));

    printer->Print(
        "this, $index$$oneofgroup$, value);$returnvalue$\n"
        "};\n"
        "\n"
        "\n",
        "index", JSFieldIndex(field),
        "oneofgroup", (field->containing_oneof() ?
                       (", " + JSOneofArray(options, field)) : ""),
        "returnvalue", JSReturnClause(field));

    printer->Print(
        "$class$.prototype.clear$name$ = function() {\n"
        "  this.set$name$($clearedvalue$);$returnvalue$\n"
        "};\n"
        "\n"
        "\n",
        "class", GetPath(options, field->containing_type()),
        "name", JSGetterName(field),
        "clearedvalue", (field->is_repeated() ? "[]" : "undefined"),
        "returnvalue", JSReturnClause(field));

  } else {
    string typed_annotation;

    // Simple (primitive) field, either singular or repeated.
    {
      typed_annotation = JSFieldTypeAnnotation(options, field,
                              /* force_optional = */ false,
                              /* force_present = */ !HasFieldPresence(field),
                              /* singular_if_not_packed = */ false,
                              /* always_singular = */ false),
      printer->Print(
          "/**\n"
          " * $fielddef$\n"
          "$comment$"
          " * @return {$type$}\n"
          " */\n",
          "fielddef", FieldDefinition(options, field),
          "comment", FieldComments(field),
          "type", typed_annotation);
    }

    printer->Print(
        "$class$.prototype.get$name$ = function() {\n",
        "class", GetPath(options, field->containing_type()),
        "name", JSGetterName(field));

    {
      printer->Print(
          "  return /** @type {$type$} */ (",
          "type", typed_annotation);
    }

    // For proto3 fields without presence, use special getters that will return
    // defaults when the field is unset, possibly constructing a value if
    // required.
    if (!HasFieldPresence(field) && !field->is_repeated()) {
      printer->Print("jspb.Message.getFieldProto3(this, $index$, $default$)",
                     "index", JSFieldIndex(field),
                     "default", Proto3PrimitiveFieldDefault(field));
    } else {
      if (field->has_default_value()) {
        printer->Print("jspb.Message.getField(this, $index$) != null ? "
                       "jspb.Message.getField(this, $index$) : $defaultValue$",
                       "index", JSFieldIndex(field),
                       "defaultValue", JSFieldDefault(field));
      } else {
        printer->Print("jspb.Message.getField(this, $index$)",
                       "index", JSFieldIndex(field));
      }
    }

    {
      printer->Print(
          ");\n"
          "};\n"
          "\n"
          "\n");
    }

    {
      printer->Print(
          "/** @param {$optionaltype$} value $returndoc$ */\n",
          "optionaltype",
          JSFieldTypeAnnotation(options, field,
                                /* force_optional = */ true,
                                /* force_present = */ !HasFieldPresence(field),
                                /* singular_if_not_packed = */ false,
                                /* always_singular = */ false),
          "returndoc", JSReturnDoc(options, field));
    }

    printer->Print(
        "$class$.prototype.set$name$ = function(value) {\n"
        "  jspb.Message.set$oneoftag$Field(this, $index$",
        "class", GetPath(options, field->containing_type()),
        "name", JSGetterName(field),
        "oneoftag", (field->containing_oneof() ? "Oneof" : ""),
        "index", JSFieldIndex(field));
    printer->Print(
        "$oneofgroup$, $type$value$rptvalueinit$$typeclose$);$returnvalue$\n"
        "};\n"
        "\n"
        "\n",
        "type", "",
        "typeclose", "",
        "oneofgroup",
        (field->containing_oneof() ? (", " + JSOneofArray(options, field))
                                   : ""),
        "returnvalue", JSReturnClause(field), "rptvalueinit",
        (field->is_repeated() ? " || []" : ""));


    if (HasFieldPresence(field)) {
      printer->Print(
          "$class$.prototype.clear$name$ = function() {\n"
          "  jspb.Message.set$oneoftag$Field(this, $index$$oneofgroup$, ",
          "class", GetPath(options, field->containing_type()),
          "name", JSGetterName(field),
          "oneoftag", (field->containing_oneof() ? "Oneof" : ""),
          "oneofgroup", (field->containing_oneof() ?
                         (", " + JSOneofArray(options, field)) : ""),
          "index", JSFieldIndex(field));
      printer->Print(
          "$clearedvalue$);$returnvalue$\n"
          "};\n"
          "\n"
          "\n",
          "clearedvalue", (field->is_repeated() ? "[]" : "undefined"),
          "returnvalue", JSReturnClause(field));
    }
  }
}

void Generator::GenerateClassExtensionFieldInfo(const GeneratorOptions& options,
                                                io::Printer* printer,
                                                const Descriptor* desc) const {
  if (IsExtendable(desc)) {
    printer->Print(
        "\n"
        "/**\n"
        " * The extensions registered with this message class. This is a "
        "map of\n"
        " * extension field number to fieldInfo object.\n"
        " *\n"
        " * For example:\n"
        " *     { 123: {fieldIndex: 123, fieldName: {my_field_name: 0}, "
        "ctor: proto.example.MyMessage} }\n"
        " *\n"
        " * fieldName contains the JsCompiler renamed field name property "
        "so that it\n"
        " * works in OPTIMIZED mode.\n"
        " *\n"
        " * @type {!Object.<number, jspb.ExtensionFieldInfo>}\n"
        " */\n"
        "$class$.extensions = {};\n"
        "\n",
        "class", GetPath(options, desc));
  }
}


void Generator::GenerateClassDeserializeBinary(const GeneratorOptions& options,
                                               io::Printer* printer,
                                               const Descriptor* desc) const {
  // TODO(cfallin): Handle lazy decoding when requested by field option and/or
  // by default for 'bytes' fields and packed repeated fields.

  printer->Print(
      "/**\n"
      " * Deserializes binary data (in protobuf wire format).\n"
      " * @param {jspb.ByteSource} bytes The bytes to deserialize.\n"
      " * @return {!$class$}\n"
      " */\n"
      "$class$.deserializeBinary = function(bytes) {\n"
      "  var reader = new jspb.BinaryReader(bytes);\n"
      "  var msg = new $class$;\n"
      "  return $class$.deserializeBinaryFromReader(msg, reader);\n"
      "};\n"
      "\n"
      "\n"
      "/**\n"
      " * Deserializes binary data (in protobuf wire format) from the\n"
      " * given reader into the given message object.\n"
      " * @param {!$class$} msg The message object to deserialize into.\n"
      " * @param {!jspb.BinaryReader} reader The BinaryReader to use.\n"
      " * @return {!$class$}\n"
      " */\n"
      "$class$.deserializeBinaryFromReader = function(msg, reader) {\n"
      "  while (reader.nextField()) {\n"
      "    if (reader.isEndGroup()) {\n"
      "      break;\n"
      "    }\n"
      "    var field = reader.getFieldNumber();\n"
      "    switch (field) {\n",
      "class", GetPath(options, desc));

  for (int i = 0; i < desc->field_count(); i++) {
    GenerateClassDeserializeBinaryField(options, printer, desc->field(i));
  }

  printer->Print(
      "    default:\n");
  if (IsExtendable(desc)) {
    printer->Print(
        "      jspb.Message.readBinaryExtension(msg, reader, $extobj$,\n"
        "        $class$.prototype.getExtension,\n"
        "        $class$.prototype.setExtension);\n"
        "      break;\n",
        "extobj", JSExtensionsObjectName(options, desc),
        "class", GetPath(options, desc));
  } else {
    printer->Print(
        "      reader.skipField();\n"
        "      break;\n");
  }

  printer->Print(
      "    }\n"
      "  }\n"
      "  return msg;\n"
      "};\n"
      "\n"
      "\n");
}

void Generator::GenerateClassDeserializeBinaryField(
    const GeneratorOptions& options,
    io::Printer* printer,
    const FieldDescriptor* field) const {

  printer->Print("    case $num$:\n",
                 "num", SimpleItoa(field->number()));

  if (field->cpp_type() == FieldDescriptor::CPPTYPE_MESSAGE) {
    printer->Print(
        "      var value = new $fieldclass$;\n"
        "      reader.read$msgOrGroup$($grpfield$value,"
        "$fieldclass$.deserializeBinaryFromReader);\n",
        "fieldclass", GetPath(options, field->message_type()),
        "msgOrGroup", (field->type() == FieldDescriptor::TYPE_GROUP) ?
                      "Group" : "Message",
        "grpfield", (field->type() == FieldDescriptor::TYPE_GROUP) ?
                    (SimpleItoa(field->number()) + ", ") : "");
  } else {
    printer->Print(
        "      var value = /** @type {$fieldtype$} */ (reader.$reader$());\n",
        "fieldtype", JSFieldTypeAnnotation(options, field, false, true,
                                           /* singular_if_not_packed = */ true,
                                           /* always_singular = */ false),
        "reader", JSBinaryReaderMethodName(field));
  }

  if (field->is_repeated() && !field->is_packed()) {
    // Repeated fields receive a |value| one at at a time; append to array
    // returned by get$name$().
    printer->Print(
        "      msg.get$name$().push(value);\n",
        "name", JSGetterName(field));
  } else {
    // Singular fields, and packed repeated fields, receive a |value| either as
    // the field's value or as the array of all the field's values; set this as
    // the field's value directly.
    printer->Print(
        "      msg.set$name$(value);\n",
        "name", JSGetterName(field));
  }

  printer->Print("      break;\n");
}

void Generator::GenerateClassSerializeBinary(const GeneratorOptions& options,
                                             io::Printer* printer,
                                             const Descriptor* desc) const {
  printer->Print(
      "/**\n"
      " * Class method variant: serializes the given message to binary data\n"
      " * (in protobuf wire format), writing to the given BinaryWriter.\n"
      " * @param {!$class$} message\n"
      " * @param {!jspb.BinaryWriter} writer\n"
      " */\n"
      "$class$.serializeBinaryToWriter = function(message, "
      "writer) {\n"
      "  message.serializeBinaryToWriter(writer);\n"
      "};\n"
      "\n"
      "\n"
      "/**\n"
      " * Serializes the message to binary data (in protobuf wire format).\n"
      " * @return {!Uint8Array}\n"
      " */\n"
      "$class$.prototype.serializeBinary = function() {\n"
      "  var writer = new jspb.BinaryWriter();\n"
      "  this.serializeBinaryToWriter(writer);\n"
      "  return writer.getResultBuffer();\n"
      "};\n"
      "\n"
      "\n"
      "/**\n"
      " * Serializes the message to binary data (in protobuf wire format),\n"
      " * writing to the given BinaryWriter.\n"
      " * @param {!jspb.BinaryWriter} writer\n"
      " */\n"
      "$class$.prototype.serializeBinaryToWriter = function (writer) {\n"
      "  var f = undefined;\n",
      "class", GetPath(options, desc));

  for (int i = 0; i < desc->field_count(); i++) {
    GenerateClassSerializeBinaryField(options, printer, desc->field(i));
  }

  if (IsExtendable(desc)) {
    printer->Print(
        "  jspb.Message.serializeBinaryExtensions(this, writer, $extobj$,\n"
        "    $class$.prototype.getExtension);\n",
        "extobj", JSExtensionsObjectName(options, desc),
        "class", GetPath(options, desc));
  }

  printer->Print(
      "};\n"
      "\n"
      "\n");
}

void Generator::GenerateClassSerializeBinaryField(
    const GeneratorOptions& options,
    io::Printer* printer,
    const FieldDescriptor* field) const {
  printer->Print(
      "  f = this.get$name$();\n",
      "name", JSGetterName(field));

  if (field->is_repeated()) {
    printer->Print(
        "  if (f.length > 0) {\n");
  } else {
    if (HasFieldPresence(field)) {
      printer->Print(
          "  if (f != null) {\n");
    } else {
      // No field presence: serialize onto the wire only if value is
      // non-default.  Defaults are documented here:
      // https://goto.google.com/lhdfm
      switch (field->cpp_type()) {
        case FieldDescriptor::CPPTYPE_INT32:
        case FieldDescriptor::CPPTYPE_INT64:
        case FieldDescriptor::CPPTYPE_UINT32:
        case FieldDescriptor::CPPTYPE_UINT64: {
          {
            printer->Print("  if (f !== 0) {\n");
          }
          break;
        }

        case FieldDescriptor::CPPTYPE_ENUM:
        case FieldDescriptor::CPPTYPE_FLOAT:
        case FieldDescriptor::CPPTYPE_DOUBLE:
          printer->Print(
              "  if (f !== 0.0) {\n");
          break;
        case FieldDescriptor::CPPTYPE_BOOL:
          printer->Print(
              "  if (f) {\n");
          break;
        case FieldDescriptor::CPPTYPE_STRING:
          printer->Print(
              "  if (f.length > 0) {\n");
          break;
        default:
          assert(false);
          break;
      }
    }
  }

  printer->Print(
      "    writer.$writer$(\n"
      "      $index$,\n"
      "      f",
      "writer", JSBinaryWriterMethodName(field),
      "name", JSGetterName(field),
      "index", SimpleItoa(field->number()));

  if (field->cpp_type() == FieldDescriptor::CPPTYPE_MESSAGE) {
    printer->Print(
        ",\n"
        "      $submsg$.serializeBinaryToWriter\n",
        "submsg", GetPath(options, field->message_type()));
  } else {
    printer->Print("\n");
  }
  printer->Print(
      "    );\n"
      "  }\n");
}

void Generator::GenerateEnum(const GeneratorOptions& options,
                             io::Printer* printer,
                             const EnumDescriptor* enumdesc) const {
  printer->Print(
      "/**\n"
      " * @enum {number}\n"
      " */\n"
      "$name$ = {\n",
      "name", GetPath(options, enumdesc));

  for (int i = 0; i < enumdesc->value_count(); i++) {
    const EnumValueDescriptor* value = enumdesc->value(i);
    printer->Print(
        "  $name$: $value$$comma$\n",
        "name", ToEnumCase(value->name()),
        "value", SimpleItoa(value->number()),
        "comma", (i == enumdesc->value_count() - 1) ? "" : ",");
  }

  printer->Print(
      "};\n"
      "\n");
}

void Generator::GenerateExtension(const GeneratorOptions& options,
                                  io::Printer* printer,
                                  const FieldDescriptor* field) const {
  string extension_scope =
      (field->extension_scope() ?
       GetPath(options, field->extension_scope()) :
       GetPath(options, field->file()));

  printer->Print(
      "\n"
      "/**\n"
      " * A tuple of {field number, class constructor} for the extension\n"
      " * field named `$name$`.\n"
      " * @type {!jspb.ExtensionFieldInfo.<$extensionType$>}\n"
      " */\n"
      "$class$.$name$ = new jspb.ExtensionFieldInfo(\n",
      "name", JSObjectFieldName(field),
      "class", extension_scope,
      "extensionType", JSFieldTypeAnnotation(
          options, field,
          /* force_optional = */ false,
          /* force_present = */ true,
          /* singular_if_not_packed = */ false,
          /* always_singular = */ false));
  printer->Print(
      "    $index$,\n"
      "    {$name$: 0},\n"
      "    $ctor$,\n"
      "     /** @type {?function((boolean|undefined),!jspb.Message=): "
      "!Object} */ (\n"
      "         $toObject$),\n"
      "    $repeated$",
      "index", SimpleItoa(field->number()),
      "name", JSObjectFieldName(field),
      "ctor", (field->cpp_type() == FieldDescriptor::CPPTYPE_MESSAGE ?
               GetPath(options, field->message_type()) : string("null")),
      "toObject", (field->cpp_type() == FieldDescriptor::CPPTYPE_MESSAGE ?
                   (GetPath(options, field->message_type()) + ".toObject") :
                   string("null")),
      "repeated", (field->is_repeated() ? "1" : "0"));

  if (options.binary) {
    printer->Print(
        ",\n"
        "    jspb.BinaryReader.prototype.$binaryReaderFn$,\n"
        "    jspb.BinaryWriter.prototype.$binaryWriterFn$,\n"
        "    $binaryMessageSerializeFn$,\n"
        "    $binaryMessageDeserializeFn$,\n"
        "    $isPacked$);\n",
        "binaryReaderFn", JSBinaryReaderMethodName(field),
        "binaryWriterFn", JSBinaryWriterMethodName(field),
        "binaryMessageSerializeFn",
        (field->cpp_type() == FieldDescriptor::CPPTYPE_MESSAGE) ?
        (GetPath(options, field->message_type()) +
         ".serializeBinaryToWriter") : "null",
        "binaryMessageDeserializeFn",
        (field->cpp_type() == FieldDescriptor::CPPTYPE_MESSAGE) ?
        (GetPath(options, field->message_type()) +
         ".deserializeBinaryFromReader") : "null",
        "isPacked", (field->is_packed() ? "true" : "false"));
  } else {
    printer->Print(");\n");
  }

  printer->Print(
      "// This registers the extension field with the extended class, so that\n"
      "// toObject() will function correctly.\n"
      "$extendName$[$index$] = $class$.$name$;\n"
      "\n",
      "extendName", JSExtensionsObjectName(options, field->containing_type()),
      "index", SimpleItoa(field->number()),
      "class", extension_scope,
      "name", JSObjectFieldName(field));
}

bool GeneratorOptions::ParseFromOptions(
    const vector< pair< string, string > >& options,
    string* error) {
  for (int i = 0; i < options.size(); i++) {
    if (options[i].first == "add_require_for_enums") {
      if (options[i].second != "") {
        *error = "Unexpected option value for add_require_for_enums";
        return false;
      }
      add_require_for_enums = true;
    } else if (options[i].first == "binary") {
      if (options[i].second != "") {
        *error = "Unexpected option value for binary";
        return false;
      }
      binary = true;
    } else if (options[i].first == "testonly") {
      if (options[i].second != "") {
        *error = "Unexpected option value for testonly";
        return false;
      }
      testonly = true;
    } else if (options[i].first == "error_on_name_conflict") {
      if (options[i].second != "") {
        *error = "Unexpected option value for error_on_name_conflict";
        return false;
      }
      error_on_name_conflict = true;
    } else if (options[i].first == "output_dir") {
      output_dir = options[i].second;
    } else if (options[i].first == "namespace_prefix") {
      namespace_prefix = options[i].second;
    } else if (options[i].first == "library") {
      library = options[i].second;
    } else {
      // Assume any other option is an output directory, as long as it is a bare
      // `key` rather than a `key=value` option.
      if (options[i].second != "") {
        *error = "Unknown option: " + options[i].first;
        return false;
      }
      output_dir = options[i].first;
    }
  }

  return true;
}

void Generator::GenerateFilesInDepOrder(
    const GeneratorOptions& options,
    io::Printer* printer,
    const vector<const FileDescriptor*>& files) const {
  // Build a std::set over all files so that the DFS can detect when it recurses
  // into a dep not specified in the user's command line.
  std::set<const FileDescriptor*> all_files(files.begin(), files.end());
  // Track the in-progress set of files that have been generated already.
  std::set<const FileDescriptor*> generated;
  for (int i = 0; i < files.size(); i++) {
    GenerateFileAndDeps(options, printer, files[i], &all_files, &generated);
  }
}

void Generator::GenerateFileAndDeps(
    const GeneratorOptions& options,
    io::Printer* printer,
    const FileDescriptor* root,
    std::set<const FileDescriptor*>* all_files,
    std::set<const FileDescriptor*>* generated) const {
  // Skip if already generated.
  if (generated->find(root) != generated->end()) {
    return;
  }
  generated->insert(root);

  // Generate all dependencies before this file's content.
  for (int i = 0; i < root->dependency_count(); i++) {
    const FileDescriptor* dep = root->dependency(i);
    GenerateFileAndDeps(options, printer, dep, all_files, generated);
  }

  // Generate this file's content.  Only generate if the file is part of the
  // original set requested to be generated; i.e., don't take all transitive
  // deps down to the roots.
  if (all_files->find(root) != all_files->end()) {
    GenerateClassesAndEnums(options, printer, root);
  }
}

bool Generator::GenerateAll(const vector<const FileDescriptor*>& files,
                            const string& parameter,
                            GeneratorContext* context,
                            string* error) const {
  vector< pair< string, string > > option_pairs;
  ParseGeneratorParameter(parameter, &option_pairs);
  GeneratorOptions options;
  if (!options.ParseFromOptions(option_pairs, error)) {
    return false;
  }


  // We're either generating a single library file with definitions for message
  // and enum types in *all* FileDescriptor inputs, or we're generating a single
  // file for each type.
  if (options.library != "") {
    string filename = options.output_dir + "/" + options.library + ".js";
    google::protobuf::scoped_ptr<io::ZeroCopyOutputStream> output(context->Open(filename));
    GOOGLE_CHECK(output.get());
    io::Printer printer(output.get(), '$');

    // Pull out all extensions -- we need these to generate all
    // provides/requires.
    vector<const FieldDescriptor*> extensions;
    for (int i = 0; i < files.size(); i++) {
      for (int j = 0; j < files[i]->extension_count(); j++) {
        const FieldDescriptor* extension = files[i]->extension(j);
        extensions.push_back(extension);
      }
    }

    GenerateHeader(options, &printer);

    std::set<string> provided;
    FindProvides(options, &printer, files, &provided);
    FindProvidesForFields(options, &printer, extensions, &provided);
    GenerateProvides(options, &printer, &provided);
    GenerateTestOnly(options, &printer);
    GenerateRequires(options, &printer, files, &provided);

    GenerateFilesInDepOrder(options, &printer, files);

    for (int i = 0; i < extensions.size(); i++) {
      if (ShouldGenerateExtension(extensions[i])) {
        GenerateExtension(options, &printer, extensions[i]);
      }
    }

    if (printer.failed()) {
      return false;
    }
  } else {
    // Collect all types, and print each type to a separate file. Pull out
    // free-floating extensions while we make this pass.
    map< string, vector<const FieldDescriptor*> > extensions_by_namespace;

    // If we're generating code in file-per-type mode, avoid overwriting files
    // by choosing the last descriptor that writes each filename and permitting
    // only those to generate code.

    // Current descriptor that will generate each filename, indexed by filename.
    map<string, const void*> desc_by_filename;
    // Set of descriptors allowed to generate files.
    set<const void*> allowed_descs;

    for (int i = 0; i < files.size(); i++) {
      // Collect all (descriptor, filename) pairs.
      map<const void*, string> descs_in_file;
      for (int j = 0; j < files[i]->message_type_count(); j++) {
        const Descriptor* desc = files[i]->message_type(j);
        string filename =
            options.output_dir + "/" + ToFileName(desc->name()) + ".js";
        descs_in_file[desc] = filename;
      }
      for (int j = 0; j < files[i]->enum_type_count(); j++) {
        const EnumDescriptor* desc = files[i]->enum_type(j);
        string filename =
            options.output_dir + "/" + ToFileName(desc->name()) + ".js";
        descs_in_file[desc] = filename;
      }

      // For each (descriptor, filename) pair, update the
      // descriptors-by-filename map, and if a previous descriptor was already
      // writing the filename, remove it from the allowed-descriptors set.
      map<const void*, string>::iterator it;
      for (it = descs_in_file.begin(); it != descs_in_file.end(); ++it) {
        const void* desc = it->first;
        const string& filename = it->second;
        if (desc_by_filename.find(filename) != desc_by_filename.end()) {
          if (options.error_on_name_conflict) {
            *error = "Name conflict: file name " + filename +
                     " would be generated by two descriptors";
            return false;
          }
          allowed_descs.erase(desc_by_filename[filename]);
        }
        desc_by_filename[filename] = desc;
        allowed_descs.insert(desc);
      }
    }

    // Generate code.
    for (int i = 0; i < files.size(); i++) {
      const FileDescriptor* file = files[i];
      for (int j = 0; j < file->message_type_count(); j++) {
        const Descriptor* desc = file->message_type(j);
        if (allowed_descs.find(desc) == allowed_descs.end()) {
          continue;
        }

        string filename = options.output_dir + "/" +
            ToFileName(desc->name()) + ".js";
        google::protobuf::scoped_ptr<io::ZeroCopyOutputStream> output(
            context->Open(filename));
        GOOGLE_CHECK(output.get());
        io::Printer printer(output.get(), '$');

        GenerateHeader(options, &printer);

        std::set<string> provided;
        FindProvidesForMessage(options, &printer, desc, &provided);
        GenerateProvides(options, &printer, &provided);
        GenerateTestOnly(options, &printer);
        GenerateRequires(options, &printer, desc, &provided);

        GenerateClass(options, &printer, desc);

        if (printer.failed()) {
          return false;
        }
      }
      for (int j = 0; j < file->enum_type_count(); j++) {
        const EnumDescriptor* enumdesc = file->enum_type(j);
        if (allowed_descs.find(enumdesc) == allowed_descs.end()) {
          continue;
        }

        string filename = options.output_dir + "/" +
            ToFileName(enumdesc->name()) + ".js";

        google::protobuf::scoped_ptr<io::ZeroCopyOutputStream> output(
            context->Open(filename));
        GOOGLE_CHECK(output.get());
        io::Printer printer(output.get(), '$');

        GenerateHeader(options, &printer);

        std::set<string> provided;
        FindProvidesForEnum(options, &printer, enumdesc, &provided);
        GenerateProvides(options, &printer, &provided);
        GenerateTestOnly(options, &printer);

        GenerateEnum(options, &printer, enumdesc);

        if (printer.failed()) {
          return false;
        }
      }
      // Pull out all free-floating extensions and generate files for those too.
      for (int j = 0; j < file->extension_count(); j++) {
        const FieldDescriptor* extension = file->extension(j);
        extensions_by_namespace[GetPath(options, files[i])]
            .push_back(extension);
      }
    }

    // Generate extensions in separate files.
    map< string, vector<const FieldDescriptor*> >::iterator it;
    for (it = extensions_by_namespace.begin();
         it != extensions_by_namespace.end();
         ++it) {
      string filename = options.output_dir + "/" +
          ToFileName(it->first) + ".js";

      google::protobuf::scoped_ptr<io::ZeroCopyOutputStream> output(
          context->Open(filename));
      GOOGLE_CHECK(output.get());
      io::Printer printer(output.get(), '$');

      GenerateHeader(options, &printer);

      std::set<string> provided;
      FindProvidesForFields(options, &printer, it->second, &provided);
      GenerateProvides(options, &printer, &provided);
      GenerateTestOnly(options, &printer);
      GenerateRequires(options, &printer, it->second, &provided);

      for (int j = 0; j < it->second.size(); j++) {
        if (ShouldGenerateExtension(it->second[j])) {
          GenerateExtension(options, &printer, it->second[j]);
        }
      }
    }
  }

  return true;
}

}  // namespace js
}  // namespace compiler
}  // namespace protobuf
}  // namespace google