rbs_additional_load.rb

require 'rbs'
require 'rbs/cli'

loader = RBS::CLI::LibraryOptions.new.loader
def loader.each_dir
  @loaded_dirs ||= Set.new
  super do |source, dir|
    next if @loaded_dirs.include? dir
    @loaded_dirs << dir
    yield source, dir
  end
end
env = RBS::Environment.from_loader(loader).resolve_type_names
rbs_builder = RBS::DefinitionBuilder.new(env:)

loader.add(library: 'prism', version: '0.30.0')
env_diff = RBS::Environment.from_loader(loader).resolve_type_names
env_diff.signatures.each do |buffer, (directives, decls)|
  env.add_signature(buffer:, directives:, decls:)
end
rbs_builder2 = RBS::DefinitionBuilder.new(env:)
rbs_builder2.build_singleton RBS::TypeName('Prism').absolute!