SelectCore deep copies attributes

lib/arel/nodes/select_core.rb

@@ -8,6 +8,13 @@ module Arel
         @projections = []
         @wheres      = []
       end
+
+      def initialize_copy other
+        super
+        @froms = @froms.map { |o| o.clone }
+        @projections = @projections.map { |o| o.clone }
+        @wheres = @wheres.map { |o| o.clone }
+      end
     end
   end
 end

spec/arel/nodes/select_core_spec.rb

@@ -0,0 +1,23 @@
+require 'spec_helper'
+
+describe Arel::Nodes::SelectCore do
+  describe "#clone" do
+    it "clones froms, projections and wheres" do
+      core = Arel::Nodes::SelectCore.new
+      core.instance_variable_set "@froms", %w[a b c]
+      core.instance_variable_set "@projections", %w[d e f]
+      core.instance_variable_set "@wheres", %w[g h i]
+
+      [:froms, :projections, :wheres].each do |array_attr|
+        core.send(array_attr).each_with_index do |o, j|
+          o.should_receive(:clone).and_return("#{o}#{j}")
+        end
+      end
+      
+      dolly = core.clone
+      dolly.froms.should == %w[a0 b1 c2]
+      dolly.projections.should == %w[d0 e1 f2]
+      dolly.wheres.should == %w[g0 h1 i2]
+    end
+  end
+end