Fix an issue with negative hunk max_size

Resolves #57.

- The `diff_size` should be an absolute value.
- Added a test to ensure that the issue does not introduce a regression.

2 files changed, 2 insertions, 2 deletions

diff --git a/lib/diff/lcs.rb b/lib/diff/lcs.rb
index c4d1cc8..b6d0a86 100644
--- a/lib/diff/lcs.rb
+++ b/lib/diff/lcs.rb
@@ -49,7 +49,7 @@ module Diff; end unless defined? Diff # rubocop:disable Style/Documentation
 #          a x b y c z p d q
 #    a b c a x b y c z
 module Diff::LCS
-  VERSION = '1.4'
+  VERSION = '1.4.1'
 end
 
 require 'diff/lcs/callbacks'
diff --git a/lib/diff/lcs/block.rb b/lib/diff/lcs/block.rb
index 430702d..fe86793 100644
--- a/lib/diff/lcs/block.rb
+++ b/lib/diff/lcs/block.rb
@@ -19,7 +19,7 @@ class Diff::LCS::Block
   end
 
   def diff_size
-    @insert.size - @remove.size
+    (@insert.size - @remove.size).abs
   end
 
   def op