ruby--ruby/spec/ruby/core/complex/plus_spec.rb

require_relative '../../spec_helper'

describe "Complex#+" do
  describe "with Complex" do
    it "adds both the real and imaginary components" do
      (Complex(1, 2) + Complex(10, 20)).should == Complex(1 + 10, 2 + 20)
      (Complex(1.5, 2.1) + Complex(100.2, -30.3)).should == Complex(1.5 + 100.2, 2.1 + (-30.3))
    end
  end

  describe "with Integer" do
    it "adds the real number to the real component of self" do
      (Complex(1, 2) + 50).should == Complex(51, 2)
      (Complex(1, 2) + 50.5).should == Complex(51.5, 2)
    end
  end

  describe "with Object" do
    it "tries to coerce self into other" do
      value = Complex(3, 9)

      obj = mock("Object")
      obj.should_receive(:coerce).with(value).and_return([2, 5])
      (value + obj).should == 2 + 5
    end
  end

  describe "passed Numeric which responds to #real? with true" do
    it "coerces the passed argument to the type of the real part and adds the resulting elements" do
      n = mock_numeric('n')
      n.should_receive(:real?).and_return(true)
      n.should_receive(:coerce).with(1).and_return([1, 4])
      (Complex(1, 2) + n).should == Complex(5, 2)
    end
  end

  describe "passed Numeric which responds to #real? with false" do
    it "coerces the passed argument to Complex and adds the resulting elements" do
      n = mock_numeric('n')
      n.should_receive(:real?).and_return(false)
      n.should_receive(:coerce).with(Complex(1, 2)).and_return([Complex(1, 2), Complex(3, 4)])
      (Complex(1, 2) + n).should == Complex(4, 6)
    end
  end
end