if_then_else

gistfile1.rb

# -*- encoding: utf-8 -*-

class IfThenElse
  def initialize(&block)
    yield self
  end

  def exec
    if @if.call
      @then.call
    else
      @else.call
    end
  end

  def if(&block)
    @if = block
  end

  def then(&block)
    @then = block
  end

  def else(&block)
    @else = block
  end
end

describe "IfThenElse#exec" do
  subject do
    IfThenElse.new do |c|
      c.if { if_result  }
      c.then { 'then' }
      c.else { 'else' }
    end
  end

  context "if が trueの場合" do
    let(:if_result) { true }
    its(:exec) {should == 'then'}
  end

  context "if が falseの場合" do
    let(:if_result) { false }
    its(:exec) { should == 'else' }
  end
end