Merge pull request #14 from Bidu/ff-random

Add Array#random!

lib/array.rb

@@ -16,4 +16,8 @@ def as_hash(keys)
   def random
     self[rand(size)]
   end
+
+  def random!
+    self.slice!(rand(size))
+  end
 end

lib/bidu/core_ext/version.rb

@@ -1,5 +1,5 @@
 module Bidu
   module CoreExt
-    VERSION = '1.2.1'
+    VERSION = '1.2.2'
   end
 end

spec/lib/array_spec.rb

@@ -92,18 +92,18 @@
   end
 
   describe '#random' do
-    let(:array) { [ 7, 5, 3 ] }
+    it_behaves_like 'a method that returns a random element', :random
+  end
 
-    (0..2).each do |index|
-      context "when random returns #{index}" do
-        before do
-          allow_any_instance_of(Array).to receive(:rand).with(array.size) { index }
-        end
+  describe '#random!' do
+    it_behaves_like 'a method that returns a random element', :random!
 
-        it 'returns the randomized index of the array' do
-          expect(array.random).to eq(array[index])
-        end
-      end
+    let(:array) { [ 8,4,2 ] }
+
+    it 'removes an the returned element' do
+      expect do
+        array.random!
+      end.to change { array.size }.by(-1)
     end
   end
 

spec/support/shared_examples/array_random.rb

@@ -0,0 +1,16 @@
+shared_examples 'a method that returns a random element' do |method|
+  let(:array) { [ 7, 5, 3 ] }
+
+  (0..2).each do |index|
+    context "when random returns #{index}" do
+      let!(:expected) { array[index] }
+      before do
+        allow_any_instance_of(Array).to receive(:rand).with(array.size) { index }
+      end
+
+      it 'returns the randomized index of the array' do
+        expect(array.public_send(method)).to eq(expected)
+      end
+    end
+  end
+end