1 files changed, 42 insertions, 39 deletions
diff --git a/lib/gitlab/diff/parser.rb b/lib/gitlab/diff/parser.rb
index 3666063bf8b..d0815fc7eea 100644
--- a/lib/gitlab/diff/parser.rb
+++ b/lib/gitlab/diff/parser.rb
@@ -4,53 +4,56 @@ module Gitlab
       include Enumerable
 
       def parse(lines)
+        return [] if lines.blank?
+
         @lines = lines
-        lines_obj = []
         line_obj_index = 0
         line_old = 1
         line_new = 1
         type = nil
 
-        @lines.each do |line|
-          next if filename?(line)
-
-          full_line = line.gsub(/\n/, '')
-
-          if line.match(/^@@ -/)
-            type = "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 if line_old <= 1 && line_new <= 1 #top of file
-            lines_obj << Gitlab::Diff::Line.new(full_line, type, line_obj_index, line_old, line_new)
-            line_obj_index += 1
-            next
-          elsif line[0] == '\\'
-            type = 'nonewline'
-            lines_obj << Gitlab::Diff::Line.new(full_line, type, line_obj_index, line_old, line_new)
-            line_obj_index += 1
-          else
-            type = identification_type(line)
-            lines_obj << Gitlab::Diff::Line.new(full_line, type, line_obj_index, line_old, line_new)
-            line_obj_index += 1
-          end
-
-
-          case line[0]
-          when "+"
-            line_new += 1
-          when "-"
-            line_old += 1
-          when "\\"
-            # No increment
-          else
-            line_new += 1
-            line_old += 1
+        # By returning an Enumerator we make it possible to search for a single line (with #find)
+        # without having to instantiate all the others that come after it.
+        Enumerator.new do |yielder|
+          @lines.each do |line|
+            next if filename?(line)
+  
+            full_line = line.gsub(/\n/, '')
+  
+            if line.match(/^@@ -/)
+              type = "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 if line_old <= 1 && line_new <= 1 #top of file
+              yielder << Gitlab::Diff::Line.new(full_line, type, line_obj_index, line_old, line_new)
+              line_obj_index += 1
+              next
+            elsif line[0] == '\\'
+              type = 'nonewline'
+              yielder << Gitlab::Diff::Line.new(full_line, type, line_obj_index, line_old, line_new)
+              line_obj_index += 1
+            else
+              type = identification_type(line)
+              yielder << Gitlab::Diff::Line.new(full_line, type, line_obj_index, line_old, line_new)
+              line_obj_index += 1
+            end
+  
+  
+            case line[0]
+            when "+"
+              line_new += 1
+            when "-"
+              line_old += 1
+            when "\\"
+              # No increment
+            else
+              line_new += 1
+              line_old += 1
+            end
           end
         end
-
-        lines_obj
       end
 
       def empty?