Fix the line code when importing PR review comments from GitHub

Pull Request Review Comments are comments on a portion of the unified
diff.

lib/gitlab/github_import/comment_formatter.rb

@@ -28,13 +28,26 @@ module Gitlab
       end
 
       def line_code
-        if on_diff?
-          Gitlab::Diff::LineCode.generate(raw_data.path, raw_data.position, 0)
-        end
+        return unless on_diff?
+
+        parsed_lines = Gitlab::Diff::Parser.new.parse(diff_hunk.lines)
+        generate_line_code(parsed_lines.to_a.last)
+      end
+
+      def generate_line_code(line)
+        Gitlab::Diff::LineCode.generate(file_path, line.new_pos, line.old_pos)
       end
 
       def on_diff?
-        raw_data.path && raw_data.position
+        diff_hunk.present?
+      end
+
+      def diff_hunk
+        raw_data.diff_hunk
+      end
+
+      def file_path
+        raw_data.path
       end
 
       def note

spec/lib/gitlab/github_import/comment_formatter_spec.rb

@@ -2,23 +2,25 @@ require 'spec_helper'
 
 describe Gitlab::GithubImport::CommentFormatter, lib: true do
   let(:project) { create(:project) }
-  let(:octocat) { OpenStruct.new(id: 123456, login: 'octocat') }
+  let(:octocat) { double(id: 123456, login: 'octocat') }
   let(:created_at) { DateTime.strptime('2013-04-10T20:09:31Z') }
   let(:updated_at) { DateTime.strptime('2014-03-03T18:58:10Z') }
-  let(:base_data) do
+  let(:base) do
     {
       body: "I'm having a problem with this.",
       user: octocat,
+      commit_id: nil,
+      diff_hunk: nil,
       created_at: created_at,
       updated_at: updated_at
     }
   end
 
-  subject(:comment) { described_class.new(project, raw_data)}
+  subject(:comment) { described_class.new(project, raw)}
 
   describe '#attributes' do
     context 'when do not reference a portion of the diff' do
-      let(:raw_data) { OpenStruct.new(base_data) }
+      let(:raw) { double(base) }
 
       it 'returns formatted attributes' do
         expected = {
@@ -36,24 +38,23 @@ describe Gitlab::GithubImport::CommentFormatter, lib: true do
     end
 
     context 'when on a portion of the diff' do
-      let(:diff_data) do
+      let(:diff) do
         {
           body: 'Great stuff',
           commit_id: '6dcb09b5b57875f334f61aebed695e2e4193db5e',
-          diff_hunk: '@@ -16,33 +16,40 @@ public class Connection : IConnection...',
-          path: 'file1.txt',
-          position: 1
+          diff_hunk: "@@ -1,5 +1,9 @@\n class User\n   def name\n-    'John Doe'\n+    'Jane Doe'",
+          path: 'file1.txt'
         }
       end
 
-      let(:raw_data) { OpenStruct.new(base_data.merge(diff_data)) }
+      let(:raw) { double(base.merge(diff)) }
 
       it 'returns formatted attributes' do
         expected = {
           project: project,
           note: "*Created by: octocat*\n\nGreat stuff",
           commit_id: '6dcb09b5b57875f334f61aebed695e2e4193db5e',
-          line_code: 'ce1be0ff4065a6e9415095c95f25f47a633cef2b_0_1',
+          line_code: 'ce1be0ff4065a6e9415095c95f25f47a633cef2b_4_3',
           author_id: project.creator_id,
           created_at: created_at,
           updated_at: updated_at
@@ -64,15 +65,10 @@ describe Gitlab::GithubImport::CommentFormatter, lib: true do
     end
 
     context 'when author is a GitLab user' do
-      let(:raw_data) { OpenStruct.new(base_data.merge(user: octocat)) }
+      let(:raw) { double(base.merge(user: octocat)) }
 
-      it 'returns project#creator_id as author_id when is not a GitLab user' do
-        expect(comment.attributes.fetch(:author_id)).to eq project.creator_id
-      end
-
-      it 'returns GitLab user id as author_id when is a GitLab user' do
+      it 'returns GitLab user id as author_id' do
         gl_user = create(:omniauth_user, extern_uid: octocat.id, provider: 'github')
-
         expect(comment.attributes.fetch(:author_id)).to eq gl_user.id
       end
     end