module ActiveRecord
class Relation
delegate :delete, :to_sql, :to => :relation
CLAUSES_METHODS = ["project", "where", "group", "order", "take", "skip", "on"].freeze
attr_reader :relation, :klass
def initialize(klass, table = nil)
@klass = klass
@relation = Arel::Table.new(table || @klass.table_name)
end
def to_a
@klass.find_by_sql(@relation.to_sql)
end
def each(&block)
to_a.each(&block)
end
def first
@relation = @relation.take(1)
to_a.first
end
for clause in CLAUSES_METHODS
class_eval %{
def #{clause}!(_#{clause})
@relation = @relation.#{clause}(_#{clause}) if _#{clause}
self
end
}
end
def select!(selection)
@relation = @relation.project(selection) if selection
self
end
def limit!(limit)
@relation = @relation.take(limit) if limit
self
end
def offset!(offset)
@relation = @relation.skip(offset) if offset
self
end
def joins!(join, join_type = nil)
if !join.blank?
if [String, Hash, Array, Symbol].include?(join.class)
@relation = @relation.join(@klass.send(:construct_join, join, nil))
else
@relation = @relation.join(join, join_type)
end
end
self
end
def conditions!(conditions)
if !conditions.blank?
conditions = @klass.send(:merge_conditions, conditions) if [String, Hash, Array].include?(conditions.class)
@relation = @relation.where(conditions)
end
self
end
private
def method_missing(method, *args, &block)
if @relation.respond_to?(method)
@relation.send(method, *args, &block)
elsif Array.instance_methods.include?(method.to_s)
to_a.send(method, *args, &block)
end
end
end
end