protobufjs 70code generation with custom option broken

[Tchang33]

protobuf.js version: 7.0.0

I'm trying to upgrade protobufjs from 6.11.3 to 7.0.0. but found code generation is broken on custom options.

here is a simplified example of .proto with custom options

syntax = "proto3";
package person;
import "google/protobuf/descriptor.proto";
/**
 * Data structure for defining  constraints on message fields
 */
message Constraints {
  message IntegerRange {
    int64   low = 1;
    int64   high = 2;
  }
  bool          isMandatory = 1;
  IntegerRange  integerRange = 2;
}

extend google.protobuf.FieldOptions {
  Constraints   constraints   = 50000;
}

message Person {
  int64                     id          = 1 [(constraints) =  { isMandatory: true }];
  string                    name        = 2;
  int64                     birthday    = 3 [(constraints) =  { isMandatory: true, integerRange: {low: 0, high: 4102448400000 } }];
 }

and the command used for code generation

 npx pbjs -t static-module -w commonjs -o src/gen/message.js model/person.proto && npx pbts -o src/gen/message.d.ts src/gen/message.js

With protobufjs 7.0.0, the code generation fails with the following error :

npx: installed 3 in 4.39s
Unexpected token in field options: isMandatory

it looks like the custom option feature has backward compatibility issue .

Could you help please ?