fixed diff issue

app/views/commits/_text_file.html.haml

+- line_old = 0
+- line_new = 0
 - lines_arr = diff.diff.lines.to_a
-- line_old = lines_arr[2].match(/-(\d)/)[0].to_i.abs rescue 0
-- line_new = lines_arr[2].match(/\+(\d)/)[0].to_i.abs rescue 0
-- lines = lines_arr[3..-1].join
-- lines.each_line do |line|
+- lines_arr.each do |line|
+  - next if line.match(/^--- a/)
+  - next if line.match(/^\+\+\+ b/)
+  - if line.match(/^@@ -/)
+    - line_old = line.match(/\-[0-9]*/)[0].to_i.abs rescue 0
+    - line_new = line.match(/\+[0-9]*/)[0].to_i.abs rescue 0
+    - next
+
   = diff_line(line, line_new, line_old)
   - if line[0] == "+"
     - line_new += 1