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path: root/spec/ruby/core/rational/divide_spec.rb
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require_relative "../../spec_helper"
require_relative 'shared/arithmetic_exception_in_coerce'

describe "Rational#/" do
  it "calls #coerce on the passed argument with self" do
    rational = Rational(3, 4)
    obj = mock("Object")
    obj.should_receive(:coerce).with(rational).and_return([1, 2])

    rational / obj
  end

  it "calls #/ on the coerced Rational with the coerced Object" do
    rational = Rational(3, 4)

    coerced_rational = mock("Coerced Rational")
    coerced_rational.should_receive(:/).and_return(:result)

    coerced_obj = mock("Coerced Object")

    obj = mock("Object")
    obj.should_receive(:coerce).and_return([coerced_rational, coerced_obj])

    (rational / obj).should == :result
  end

  it_behaves_like :rational_arithmetic_exception_in_coerce, :/
end

describe "Rational#/ when passed an Integer" do
  it "returns self divided by other as a Rational" do
    (Rational(3, 4) / 2).should eql(Rational(3, 8))
    (Rational(2, 4) / 2).should eql(Rational(1, 4))
    (Rational(6, 7) / -2).should eql(Rational(-3, 7))
  end

  it "raises a ZeroDivisionError when passed 0" do
    -> { Rational(3, 4) / 0 }.should raise_error(ZeroDivisionError)
  end
end

describe "Rational#/ when passed a Rational" do
  it "returns self divided by other as a Rational" do
    (Rational(3, 4) / Rational(3, 4)).should eql(Rational(1, 1))
    (Rational(2, 4) / Rational(1, 4)).should eql(Rational(2, 1))

    (Rational(2, 4) / 2).should == Rational(1, 4)
    (Rational(6, 7) / -2).should == Rational(-3, 7)
  end

  it "raises a ZeroDivisionError when passed a Rational with a numerator of 0" do
    -> { Rational(3, 4) / Rational(0, 1) }.should raise_error(ZeroDivisionError)
  end
end

describe "Rational#/ when passed a Float" do
  it "returns self divided by other as a Float" do
    (Rational(3, 4) / 0.75).should eql(1.0)
    (Rational(3, 4) / 0.25).should eql(3.0)
    (Rational(3, 4) / 0.3).should eql(2.5)

    (Rational(-3, 4) / 0.3).should eql(-2.5)
    (Rational(3, -4) / 0.3).should eql(-2.5)
    (Rational(3, 4) / -0.3).should eql(-2.5)
  end

  it "returns infinity when passed 0" do
    (Rational(3, 4) / 0.0).infinite?.should eql(1)
    (Rational(-3, -4) / 0.0).infinite?.should eql(1)

    (Rational(-3, 4) / 0.0).infinite?.should eql(-1)
    (Rational(3, -4) / 0.0).infinite?.should eql(-1)
  end
end