# encoding: utf-8

require 'spec_helper'

describe Relation do
  context 'Relations are writable' do
    let(:relation) do
      Relation.new(
        [ [ :id, Integer ], [ :name, String, { :required => false } ] ],
        [ [ 1, 'John Doe' ], [ 2, 'Jane Doe' ], [ 3, 'Jane Roe' ] ]
      )
    end

    it 'Rename#insert and #delete of a disjoint relation are symmetrical' do
      rename = relation.rename(:id => :other_id)
      other  = [ [ 4, 'John Doe' ] ]
      rename.insert(other).delete(other).should == rename
    end

    it 'Projection#insert and #delete of a disjoint relation are symmetrical' do
      projection = relation.project([ :id ])
      other      = [ [ 4 ] ]
      projection.insert(other).delete(other).should == projection
    end

    it 'Extension#insert and #delete of a disjoint relation are symmetrical' do
      extension = relation.extend { |r| r.add(:age, 30) }
      other     = Relation.new(relation.header, [ [ 4, 'John Doe' ] ]).extend(extension.extensions)
      extension.insert(other).delete(other).should == extension
    end

    it 'Restriction#insert and #delete of a disjoint relation are symmetrical' do
      restriction = relation.restrict { |r| r.id.gte(1) }
      other       = [ [ 4, 'John Doe' ] ]
      restriction.insert(other).delete(other).should == restriction
    end

    it 'Join#insert and #delete of a disjoint relation are symmetrical' do
      join  = relation + Relation.new([ [ :id, Integer ] ], [ [ 1 ] ])
      other = [ [ 4, 'John Doe' ] ]
      join.insert(other).delete(other).should == join
    end

    it 'Difference#insert and #delete of a disjoint relation are symmetrical' do
      difference = relation - relation
      other      = [ [ 4, 'John Doe' ] ]
      difference.insert(other).delete(other).should == difference
    end

    it 'Union#insert and #delete of a disjoint relation are symmetrical' do
      union  = relation | relation
      other  = [ [ 4, 'John Doe' ] ]
      union.insert(other).delete(other).should == union
    end

    it 'Intersection#insert and #delete of a disjoint relation are symmetrical' do
      intersection = relation & relation
      other        = [ [ 4, 'John Doe' ] ]
      intersection.insert(other).delete(other).should == intersection
    end

    it 'Order#insert and #delete of a disjoint relation are symmetrical' do
      order = relation.sort_by(relation.header)
      other = Relation.new(relation.header, [ [ 4, 'John Doe' ] ]).sort_by(relation.header)
      order.insert(other).delete(other).should == order
    end
  end
end