diff options
Diffstat (limited to 'spec/ruby/core/complex/multiply_spec.rb')
-rw-r--r-- | spec/ruby/core/complex/multiply_spec.rb | 48 |
1 files changed, 46 insertions, 2 deletions
diff --git a/spec/ruby/core/complex/multiply_spec.rb b/spec/ruby/core/complex/multiply_spec.rb index b43855f695..35bf7c8455 100644 --- a/spec/ruby/core/complex/multiply_spec.rb +++ b/spec/ruby/core/complex/multiply_spec.rb @@ -1,5 +1,49 @@ -require_relative '../../shared/complex/multiply' +require_relative '../../spec_helper' describe "Complex#*" do - it_behaves_like :complex_multiply, :* + describe "with Complex" do + it "multiplies according to the usual rule for complex numbers: (a + bi) * (c + di) = ac - bd + (ad + bc)i" do + (Complex(1, 2) * Complex(10, 20)).should == Complex((1 * 10) - (2 * 20), (1 * 20) + (2 * 10)) + (Complex(1.5, 2.1) * Complex(100.2, -30.3)).should == Complex((1.5 * 100.2) - (2.1 * -30.3), (1.5 * -30.3) + (2.1 * 100.2)) + end + end + + describe "with Integer" do + it "multiplies both parts of self by the given Integer" do + (Complex(3, 2) * 50).should == Complex(150, 100) + (Complex(-3, 2) * 50.5).should == Complex(-151.5, 101) + 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 "with a Numeric which responds to #real? with true" do + it "multiples both parts of self by other" do + other = mock_numeric('other') + real = mock_numeric('real') + imag = mock_numeric('imag') + other.should_receive(:real?).and_return(true) + real.should_receive(:*).with(other).and_return(1) + imag.should_receive(:*).with(other).and_return(2) + (Complex(real, imag) * other).should == Complex(1, 2) + end + + describe "with a Numeric which responds to #real? with false" do + it "coerces the passed argument to Complex and multiplies the resulting elements" do + complex = Complex(3, 0) + other = mock_numeric('other') + other.should_receive(:real?).any_number_of_times.and_return(false) + other.should_receive(:coerce).with(complex).and_return([5, 2]) + (complex * other).should == 10 + end + end + end end |