--- /dev/null
+++ b/vendor/diff-display/Rakefile
@@ -0,0 +1,13 @@
+require 'rake'
+require 'rake/testtask'
+require 'rake/rdoctask'
+
+desc 'Default: run unit tests.'
+task :default => :test
+
+desc 'Test the resource_paths plugin.'
+Rake::TestTask.new(:test) do |t|
+  t.libs << 'lib'
+  t.pattern = 'test/**/*_test.rb'
+  t.verbose = true
+end
\ No newline at end of file

--- a/vendor/diff-display/lib/diff/display/unified.rb
+++ b/vendor/diff-display/lib/diff/display/unified.rb
@@ -304,8 +304,8 @@ module Diff #:nodoc:#
         #   process --> identify_block --> process_block --> process_line 
         #
         def process(line)
-          return if ['++', '--'].include?(line[0,2])
-
+          return if is_extra_header_line?(line)
+          
           if match = LINE_NUM_RE.match(line) 
             identify_block
             add_separator unless @offset_changed.zero?
@@ -316,7 +316,7 @@ module Diff #:nodoc:#
           end
 
           new_line_type, line = LINE_TYPES[car(line)], cdr(line)
-
+          
           # Add line to the buffer if it's the same diff line type
           # as the previous line
           # 
@@ -355,6 +355,14 @@ module Diff #:nodoc:#
         end
 
         protected 
+        
+          def is_extra_header_line?(line)
+            return true if ['++', '--'].include?(line[0,2])
+            return true if line =~ /^(new|delete) file mode [0-9]+$/
+            return true if line =~ /^diff \-\-git/
+            return true if line =~ /^index \w+\.\.\w+ [0-9]+$/
+            false
+          end
 
           def identify_block
             if @prev_line_type.eql?(LINE_TYPES['-']) and @line_type.eql?(LINE_TYPES['+'])
@@ -370,13 +378,11 @@ module Diff #:nodoc:#
 
           def process_block(diff_line_type, new = false, old = false)
             push Block.send(diff_line_type)
-
             # Mod block
-            if diff_line_type.eql?(:mod) and @prev_buffer.size & @buffer.size == 1
+            if diff_line_type.eql?(:mod) && @prev_buffer.size && @buffer.size == 1
               process_line(@prev_buffer.first, @buffer.first)
               return
             end
-
             unroll_prev_buffer if old
             unroll_buffer      if new 
           end

--- a/vendor/diff-display/test/abstract_unit.rb
+++ b/vendor/diff-display/test/abstract_unit.rb
@@ -1,12 +1,15 @@
+require 'test/unit'
+require 'yaml'
+
 $:.unshift(File.dirname(__FILE__) + '/../lib')
 require 'diff/display/unified'
 
 module Kernel
   def load_diffs(*diffs)
     loaded_diffs = Hash.new({})
-    diff_path    = 'diffs/'
+    diff_path    = File.join(File.dirname(__FILE__), 'diffs')
     diffs.each do |diff_name|
-      diff = IO.readlines(diff_path + diff_name.id2name + '.diff')
+      diff = IO.readlines(File.join(diff_path, diff_name.id2name + '.diff'))
       data = Diff::Display::Unified::Generator.run(diff)
       loaded_diffs[diff_name] = {:diff => diff, :data => data}
     end
@@ -14,7 +17,7 @@ module Kernel
   end
   alias_method :load_diff, :load_diffs
 
-  def load_all_diffs(path = 'diffs')
+  def load_all_diffs(path = File.join(File.dirname(__FILE__), 'diffs'))
     load_diffs *Dir.glob(path + '/*.diff').map {|d| File.basename(d, '.*').intern}
   end
 

--- /dev/null
+++ b/vendor/diff-display/test/diff_display_unified_test.rb
@@ -0,0 +1,33 @@
+require File.dirname(__FILE__) + '/abstract_unit'
+
+class DisplayUnifiedTest < Test::Unit::TestCase
+
+  def setup
+    @diffs = load_all_diffs
+    @diffs_with_inline_changes = load_diffs :inline_changes
+  end
+
+  def test_parity_of_diffs_and_data_objects
+    @diffs.keys.each do |d|
+      assert_equal(@diffs[d][:data].normalize_diff_object, 
+                   @diffs[d][:diff].normalize_diff, 
+                   "Data object and diff file for #{d} don't match")
+   end
+  end
+
+  def test_parity_of_inline_changes
+    @diffs_with_inline_changes.keys.each do |d|
+      assert_equal(@diffs[d][:data].data_inline_line_numbers,
+                   @diffs[d][:diff].diff_inline_line_numbers,
+                   "Inline change line numbers don't match up for #{d}")
+    end
+  end
+  
+  # def test_edgecase
+  #   diff = load_diff(:edgecase1_diff)[:edgecase1_diff]
+  #   assert_equal(diff[:data].normalize_diff_object, 
+  #                diff[:diff].normalize_diff, 
+  #                "Data object and diff file for #{diff} don't match")
+  # end
+
+end

--- /dev/null
+++ b/vendor/diff-display/test/diffs/edgecase1_diff.diff
@@ -0,0 +1,11 @@
+--- a/one.txt
++++ b/one.txt
+@@ -193,7 +193,21 @@ module One
+       pre yada yada
+-        
++
++      foo
++      bar
++      baz
++      
+       post yada yada
\ No newline at end of file

--- /dev/null
+++ b/vendor/diff-display/test/parity_between_diff_and_data_test.rb
@@ -0,0 +1,26 @@
+require File.dirname(__FILE__) + '/abstract_unit'
+
+class ParityBetweenDiffAndDataTest < Test::Unit::TestCase
+
+  def setup
+    @diffs = load_all_diffs
+    @diffs_with_inline_changes = load_diffs :inline_changes
+  end
+
+  def test_parity_of_diffs_and_data_objects
+    @diffs.keys.each do |d|
+      assert_equal(@diffs[d][:data].normalize_diff_object, 
+                   @diffs[d][:diff].normalize_diff, 
+                   "Data object and diff file for #{d} don't match")
+   end
+  end
+
+  def test_parity_of_inline_changes
+    @diffs_with_inline_changes.keys.each do |d|
+      assert_equal(@diffs[d][:data].data_inline_line_numbers,
+                   @diffs[d][:diff].diff_inline_line_numbers,
+                   "Inline change line numbers don't match up for #{d}")
+    end
+  end
+
+end

--- a/vendor/diff-display/test/tc_diff_display_unified.rb
+++ /dev/null
@@ -1,28 +0,0 @@
-require 'abstract_unit'
-require 'test/unit'
-require 'yaml'
-
-class TestDiffDisplay < Test::Unit::TestCase
-
-  def setup
-    @diffs = load_all_diffs
-    @diffs_with_inline_changes = load_diffs :inline_changes
-  end
-
-  def test_parity_of_diffs_and_data_objects
-    @diffs.keys.each do |d|
-      assert_equal(@diffs[d][:data].normalize_diff_object, 
-                   @diffs[d][:diff].normalize_diff, 
-                   "Data object and diff file for #{d} don't match")
-   end
-  end
-
-  def test_parity_of_inline_changes
-    @diffs_with_inline_changes.keys.each do |d|
-      assert_equal(@diffs[d][:data].data_inline_line_numbers,
-                   @diffs[d][:diff].diff_inline_line_numbers,
-                   "Inline change line numbers don't match up for #{d}")
-    end
-  end
-
-end

--- a/vendor/diff-display/test/tc_parity_between_diff_and_data.rb
+++ /dev/null
@@ -1,28 +0,0 @@
-require 'abstract_unit'
-require 'test/unit'
-require 'yaml'
-
-class TestDiffDisplay < Test::Unit::TestCase
-
-  def setup
-    @diffs = load_all_diffs
-    @diffs_with_inline_changes = load_diffs :inline_changes
-  end
-
-  def test_parity_of_diffs_and_data_objects
-    @diffs.keys.each do |d|
-      assert_equal(@diffs[d][:data].normalize_diff_object, 
-                   @diffs[d][:diff].normalize_diff, 
-                   "Data object and diff file for #{d} don't match")
-   end
-  end
-
-  def test_parity_of_inline_changes
-    @diffs_with_inline_changes.keys.each do |d|
-      assert_equal(@diffs[d][:data].data_inline_line_numbers,
-                   @diffs[d][:diff].diff_inline_line_numbers,
-                   "Inline change line numbers don't match up for #{d}")
-    end
-  end
-
-end