add onpdiff tests

spec/components/onpdiff_spec.rb

@@ -0,0 +1,35 @@
+require 'spec_helper'
+require 'onpdiff'
+
+describe ONPDiff do
+
+  describe "diff" do
+
+    it "returns an empty array when there is no content to diff" do
+      ONPDiff.new("", "").diff.should == []
+    end
+
+    it "returns an array with the operation code for each element" do
+      ONPDiff.new("abcd", "abef").diff.should == [["a", :common], ["b", :common], ["e", :add], ["f", :add], ["c", :delete], ["d", :delete]]
+    end
+
+  end
+
+  describe "short_diff" do
+
+    it "returns an empty array when there is no content to diff" do
+      ONPDiff.new("", "").short_diff.should == []
+    end
+
+    it "returns an array with the operation code for each element" do
+      ONPDiff.new("abc", "acd").short_diff.should == [["a", :common], ["b", :delete], ["c", :common], ["d", :add]]
+    end
+
+    it "returns an array with sequencially similar operations merged" do
+      ONPDiff.new("abcd", "abef").short_diff.should == [["ab", :common], ["ef", :add], ["cd", :delete]]
+    end
+
+  end
+
+end
+