Contents

# encoding: utf-8

require 'spec_helper'

describe Optimizer::Algebra::Restriction::Contradiction, '#optimizable?' do
  subject { object.optimizable? }

  let(:header)   { Relation::Header.new([ [ :id, Integer ] ]) }
  let(:base)     { Relation.new(header, [ [ 1 ] ].each)       }
  let(:relation) { base.restrict { predicate }                }
  let(:object)   { described_class.new(relation)              }

  before do
    object.operation.should be_kind_of(Algebra::Restriction)
  end

  context 'when the predicate is a contradiction' do
    let(:predicate) { Function::Proposition::Contradiction.instance }

    it { should be(true) }
  end

  context 'when the predicate is not a contradiction' do
    let(:predicate) { Function::Proposition::Tautology.instance }

    it { should be(false) }
  end

  context 'when the predicate is false' do
    let(:predicate) { false }

    it { should be(true) }
  end

  context 'when the predicate is true' do
    let(:predicate) { true }

    it { should be(false) }
  end

  context 'when the predicate is a Proc' do
    let(:predicate) { proc { false } }

    it { should be(false) }
  end
end

Version data entries

4 entries across 4 versions & 1 rubygems

Version	Path
veritas-optimizer-0.0.7	spec/unit/veritas/optimizer/algebra/restriction/contradiction/optimizable_spec.rb
veritas-optimizer-0.0.6	spec/unit/veritas/optimizer/algebra/restriction/contradiction/optimizable_spec.rb
veritas-optimizer-0.0.5	spec/unit/veritas/optimizer/algebra/restriction/contradiction/optimizable_spec.rb
veritas-optimizer-0.0.4	spec/unit/veritas/optimizer/algebra/restriction/contradiction/optimizable_spec.rb