ruby--ruby/spec/ruby/core/hash/keys_spec.rb

require_relative '../../spec_helper'
require_relative 'fixtures/classes'

describe "Hash#keys" do

  it "returns an array with the keys in the order they were inserted" do
    {}.keys.should == []
    {}.keys.should be_kind_of(Array)
    Hash.new(5).keys.should == []
    Hash.new { 5 }.keys.should == []
    { 1 => 2, 4 => 8, 2 => 4 }.keys.should == [1, 4, 2]
    { 1 => 2, 2 => 4, 4 => 8 }.keys.should be_kind_of(Array)
    { nil => nil }.keys.should == [nil]
  end

  it "uses the same order as #values" do
    h = { 1 => "1", 2 => "2", 3 => "3", 4 => "4" }

    h.size.times do |i|
      h[h.keys[i]].should == h.values[i]
    end
  end
end