1require_relative '../../spec_helper'
2
3describe "Hash#rassoc" do
4  before :each do
5    @h = {apple: :green, orange: :orange, grape: :green, banana: :yellow}
6  end
7
8  it "returns an Array if the argument is a value of the Hash" do
9    @h.rassoc(:green).should be_an_instance_of(Array)
10  end
11
12  it "returns a 2-element Array if the argument is a value of the Hash" do
13    @h.rassoc(:orange).size.should == 2
14  end
15
16  it "sets the first element of the Array to the key of the located value" do
17    @h.rassoc(:yellow).first.should == :banana
18  end
19
20  it "sets the last element of the Array to the located value" do
21    @h.rassoc(:yellow).last.should == :yellow
22  end
23
24  it "only returns the first matching key-value pair" do
25    @h.rassoc(:green).should == [:apple, :green]
26  end
27
28  it "uses #== to compare the argument to the values" do
29    @h[:key] = 1.0
30    1.should == 1.0
31    @h.rassoc(1).should eql [:key, 1.0]
32  end
33
34  it "returns nil if the argument is not a value of the Hash" do
35    @h.rassoc(:banana).should be_nil
36  end
37
38  it "returns nil if the argument is not a value of the Hash even when there is a default" do
39    Hash.new(42).merge!( foo: :bar ).rassoc(42).should be_nil
40    Hash.new{|h, k| h[k] = 42}.merge!( foo: :bar ).rassoc(42).should be_nil
41  end
42end
43