1 files changed, 45 insertions, 0 deletions
diff --git a/lib/gitlab/word_diff/line_processor.rb b/lib/gitlab/word_diff/line_processor.rb
new file mode 100644
index 00000000000..49263962dd6
--- /dev/null
+++ b/lib/gitlab/word_diff/line_processor.rb
@@ -0,0 +1,45 @@
+# frozen_string_literal: true
+
+# Converts a line from `git diff --word-diff=porcelain` output into a segment
+#
+# Possible options:
+# 1. Diff hunk
+# 2. Chunk
+# 3. Newline
+module Gitlab
+  module WordDiff
+    class LineProcessor
+      def initialize(line)
+        @line = line
+      end
+
+      def extract
+        return if empty_line?
+        return Segments::DiffHunk.new(full_line) if diff_hunk?
+        return Segments::Newline.new if newline_delimiter?
+
+        Segments::Chunk.new(full_line)
+      end
+
+      private
+
+      attr_reader :line
+
+      def diff_hunk?
+        line =~ /^@@ -/
+      end
+
+      def empty_line?
+        full_line == ' '
+      end
+
+      def newline_delimiter?
+        full_line == '~'
+      end
+
+      def full_line
+        @full_line ||= line.delete("\n")
+      end
+    end
+  end
+end