e77a650432097e3eeb867dfe4fec5235450414bf,src/python/pants/backend/graph_info/tasks/list_owners.py,ListOwners,console_output,#ListOwners#Any#,25

Before Change

    if not sources:
      raise TaskError("No source was specified")
    elif len(sources) > 1:
      raise TaskError("Too many sources specified.")
    lazy_source_mapper = LazySourceMapper(self.context.address_mapper, self.context.build_graph)
    for source in sources:
      target_addresses_for_source = lazy_source_mapper.target_addresses_for_source(source)
      for address in target_addresses_for_source:

After Change

    if not sources:
      raise TaskError("No source was specified")
    lazy_source_mapper = LazySourceMapper(self.context.address_mapper, self.context.build_graph)
    owner_info = {}
    for source in sources:
      owner_info[source] = []
      target_addresses_for_source = lazy_source_mapper.target_addresses_for_source(source)
      for address in target_addresses_for_source:
        owner_info[source].append(address.spec)
    if self.get_options().output_format == "json":
      yield json.dumps(owner_info, indent=4, separators=(",", ": "))
    else:
      if len(sources) > 1:
        raise TaskError("Too many sources specified for {} output format."
                        .format(self.get_options().output_format))

Instances