scalapb option with retain_source_code_info doesn't work

[haneul]

We used an old version of rules_scala for a while, and recently tried to upgrade but found that scalapb option retain_source_code_info doesn't work as expected.

Added an example into https://github.com/haneul/scalapbtest
The current master HEAD doesn't contain code info in the generated code.
While it works with https://github.com/haneul/scalapbtest/tree/cd723982dae484796e31bbd9237e6cd8cd4fbd9c

syntax = "proto3";

import "scalapb/scalapb.proto";

option (scalapb.options) = {
  retain_source_code_info: true
};

enum TestEnum {
  // test1
  TEST1=0;
  // test2
  Test2=1;
}

// hello world
message TestEnumReq {
  // enumfield
  TestEnum field = 1;
  // this is account
  string account = 2;
}

Looking into the generated TestEnum.scala
working version:

object TestEnum extends _root_.scalapb.GeneratedEnumCompanion[TestEnum] {
  implicit def enumCompanion: _root_.scalapb.GeneratedEnumCompanion[TestEnum] = this
  /** test1
    */
  @SerialVersionUID(0L)
  case object TEST1 extends TestEnum {
    val value = 0
    val index = 0
    val name = "TEST1"
    override def isTest1: _root_.scala.Boolean = true
  }

non-working version:

object TestEnum extends _root_.scalapb.GeneratedEnumCompanion[TestEnum] {
  implicit def enumCompanion: _root_.scalapb.GeneratedEnumCompanion[TestEnum] = this
  @SerialVersionUID(0L)
  case object TEST1 extends TestEnum {
    val value = 0
    val index = 0
    val name = "TEST1"
    override def isTest1: _root_.scala.Boolean = true
  }

Looking into history of rules_scala, the behavior changed after 1162eea

Not sure what exactly caused the issue though.

[simuons]

Hi, @haneul,

this happens because descriptor_set_out (the output of proto_library) does not include source info. To change that you have to add build --protocopt=--include_source_info to your .bazelrc then scalapb should see source info.

Let me know if that helps.