rails 3.2.13 scopes auto merging :(

gistfile1.txt

# Как и ожидалось:

  irb(main):151:0> User.where(:id => [1,2]).where(:id => [3,4]).to_sql
  => "SELECT \"users\".* FROM \"users\"  WHERE \"users\".\"id\" IN (1, 2) AND \"users\".\"id\" IN (3, 4)"

# Теперь определяем скоуп:
  irb(main):148:0> User.instance_eval { scope :with_ids, ->(ids) { where(:id => ids) } }

# И имеем полнешую хуйню:
  irb(main):150:0> User.with_ids([1,2]).with_ids([3,4]).to_sql
  => "SELECT \"users\".* FROM \"users\"  WHERE \"users\".\"id\" IN (3, 4)"