Send my love to Ruby
Over at the Rubinius project, in between hatching plots to take over the world, we fit in some time for recreation. For example, we’ve got this masochistic interest in writing RSpec compatible specs for the Ruby core library. One of the challenges there is the large number of aliased methods that Ruby has. Using RSpec’s shared behaviors as an example, I’ve created a flavor of shared behaviors in our mini_rspec implementation. As the code below shows, this makes it straightforward to spec all these aliases.
1 hash_store = shared "Hash#store" do |cmd|
2 describe "Hash##{cmd}" do
3 it "associates the key with the value and return the value" do
4 h = { :a => 1 }
5 (h.send(cmd, :b, 2).should == 2
6 h.should == {:b=>2, :a=>1}
7 end
8
9 it "duplicates and freezes string keys" do
10 key = "foo"
11 h = {}
12 h.send(cmd, key, 0)
13 key << "bar"
14
15 h.should == { "foo" => 0 }
16 h.keys[0].frozen?.should == true
17 end
18
19 it "duplicates string keys using dup semantics" do
20 # dup doesn't copy singleton methods
21 key = "foo"
22 def key.reverse() "bar" end
23 h = {}
24 h.send(cmd, key, 0)
25
26 h.keys[0].reverse.should == "oof"
27 end
28
29 it "raises TypeError if called on a frozen instance" do
30 should_raise(TypeError) { hash.send(cmd, 1, 2) }
31 end
32 end
33 end
34
35 describe "Hash#[]=" do
36 it_behaves_like(hash_store, :[]=)
37 end
The very cool thing about this is how useful Ruby’s send method is. And in Rubinius, it gets even cooler, as you’ll see in part II
