Merge pull request #3 from porras/exceptions

Raise specific exceptions

lib/data_uri/uri.rb

@@ -12,7 +12,7 @@ def initialize(*args)
       if args.length == 1
         uri = args.first.to_s
         unless uri.match(/^data:/)
-          raise 'Invalid Data URI: ' + args.first.inspect
+          raise URI::InvalidURIError.new('Invalid Data URI: ' + args.first.inspect)
         end
         @scheme = 'data'
         @opaque = uri[5 .. -1]
@@ -34,7 +34,7 @@ def initialize(*args)
         @data = @data[7 .. -1]
       end
       unless /^,/.match(@data)
-        raise 'Invalid data URI'
+        raise URI::InvalidURIError.new('Invalid data URI')
       end
       @data = @data[1 .. -1]
       @data = base64 ? Base64.decode64(@data) : URI.decode(@data)

test/test_data_uri.rb

@@ -91,6 +91,13 @@
 
     end
 
+    describe "an invalid data URI" do
+      it "should raise an error" do
+        proc { URI::Data.new("This is not a data URI") }.must_raise(URI::InvalidURIError)
+        proc { URI::Data.new("data:Neither this") }.must_raise(URI::InvalidURIError)
+      end
+    end
+
   end
 
   describe "building" do