Protobuf: Ruby: message with Google::Protobuf::Map cannot be converted to Hash

[mxmCherry]

Ruby protobuf message cannot be converted to hash if it uses map<...> fields.

Probably, because of https://github.com/google/protobuf/blob/master/ruby/ext/google/protobuf_c/message.c#L371

---

Gem version:

gem 'google-protobuf', '3.0.0.alpha.5.0.5.1'

Proto:

// compile:
//   protoc --ruby_out=. xxx.proto

syntax = "proto3";
package xxx;

message WithMap {
    map<string,string> map = 1;
}

Compiled proto:

# Generated by the protocol buffer compiler.  DO NOT EDIT!
# source: xxx.proto

require 'google/protobuf'

Google::Protobuf::DescriptorPool.generated_pool.build do
  add_message "xxx.WithMap" do
    map :map, :string, :string, 1
  end
end

module Xxx
  WithMap = Google::Protobuf::DescriptorPool.generated_pool.lookup("xxx.WithMap").msgclass
end

This fails:

require_relative 'xxx'

p Xxx::WithMap.new.to_h

With:

debug.rb:3:in `to_h': wrong argument type Google::Protobuf::Map (expected Google::Protobuf::RepeatedField) (TypeError)
    from debug.rb:3:in `<main>'

[mxmCherry]

Seems to be resolved in https://github.com/google/protobuf/pull/396 , but still not merged.

[acoffman]

I am also experiencing this issue; is there any expectation that this will be fixed in the near future? I would offer to try and patch it myself, but it looks like there's an outstanding PR that fixes it already there. Is there something I can do to help move it along?

[ebenoist]

Agreed-- what can be done here to get this fix in?

[haberman]

Wow, sorry this bug went unfixed for so long. I've assigned it to myself now.