require_relative '../../spec_helper' describe :complex_minus, shared: true do describe "with Complex" do it "subtracts 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 "subtracts the real number from the real component of self" do (Complex(1, 2) - 50).should == Complex(-49, 2) (Complex(1, 2) - 50.5).should == Complex(-49.5, 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 subtracts 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(-3, 2) end end describe "passed Numeric which responds to #real? with false" do it "coerces the passed argument to Complex and subtracts 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(-2, -2) end end end