require_relative '../../spec_helper' require_relative 'fixtures/classes' describe "Hash#invert" do it "returns a new hash where keys are values and vice versa" do { 1 => 'a', 2 => 'b', 3 => 'c' }.invert.should == { 'a' => 1, 'b' => 2, 'c' => 3 } end it "handles collisions by overriding with the key coming later in keys()" do h = { a: 1, b: 1 } override_key = h.keys.last h.invert[1].should == override_key end it "compares new keys with eql? semantics" do h = { a: 1.0, b: 1 } i = h.invert i[1.0].should == :a i[1].should == :b end it "does not return subclass instances for subclasses" do HashSpecs::MyHash[1 => 2, 3 => 4].invert.class.should == Hash HashSpecs::MyHash[].invert.class.should == Hash end end