advisory_locks_spec.rb

describe 'test' do
  it 'locks stuff' do
    ActiveRecord::Base.connection.execute <<-SQL
      BEGIN;
      SELECT pg_advisory_lock(420);
    SQL

    Thread.new do
      res = ActiveRecord::Base.connection.execute <<-SQL
        SELECT pg_try_advisory_lock(420);
      SQL

      expect(res.getvalue(0, 0)).to eq('f')
    end.join

    ActiveRecord::Base.connection.execute 'ROLLBACK;'
  end
end