class Arel::Nodes::UpdateStatement

def eql?(other)
  self.class == other.class &&
    self.relation == other.relation &&
    self.wheres == other.wheres &&
    self.values == other.values &&
    self.groups == other.groups &&
    self.havings == other.havings &&
    self.orders == other.orders &&
    self.limit == other.limit &&
    self.offset == other.offset &&
    self.key == other.key
end

def hash
  [@relation, @wheres, @values, @orders, @limit, @offset, @key].hash
end

def initialize(relation = nil)
  super()
  @relation = relation
  @wheres   = []
  @values   = []
  @groups   = []
  @havings  = []
  @orders   = []
  @limit    = nil
  @offset   = nil
  @key      = nil
end

def initialize_copy(other)
  super
  @wheres = @wheres.clone
  @values = @values.clone
end