Merge branch 'show-commit-status-from-source-project' into 'master'

Show commits from source project. Be consistent with pipeline

## What does this MR do?

Show commits from source project instead of target project.

## Why was this MR needed?

To be consistent.

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- [ ] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- Tests
  - [x] Added for this feature/bug

## What are the relevant issue numbers?

Closes #3596

See merge request !6658

5 files changed, 47 insertions, 5 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 21f2bec867f..2e25f0b2ceb 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -107,6 +107,7 @@ Please view this file on the master branch, on stable branches it's out of date.
   - Add visibility level to project repository
   - Fix robots.txt disallowing access to groups starting with "s" (Matt Harrison)
   - Close open merge request without source project (Katarzyna Kobierska Ula Budziszewska)
+  - Fix showing commits from source project for merge request !6658
   - Fix that manual jobs would no longer block jobs in the next stage. !6604
   - Add configurable email subject suffix (Fu Xu)
   - Use defined colour for a language when available !6748 (nilsding)
diff --git a/app/models/merge_request_diff.rb b/app/models/merge_request_diff.rb
index b8a10b7968e..dd65a9a8b86 100644
--- a/app/models/merge_request_diff.rb
+++ b/app/models/merge_request_diff.rb
@@ -299,8 +299,10 @@ class MergeRequestDiff < ActiveRecord::Base
   end
 
   def keep_around_commits
-    repository.keep_around(start_commit_sha)
-    repository.keep_around(head_commit_sha)
-    repository.keep_around(base_commit_sha)
+    [repository, merge_request.source_project.repository].each do |repo|
+      repo.keep_around(start_commit_sha)
+      repo.keep_around(head_commit_sha)
+      repo.keep_around(base_commit_sha)
+    end
   end
 end
diff --git a/app/views/projects/merge_requests/show/_commits.html.haml b/app/views/projects/merge_requests/show/_commits.html.haml
index 0b05785430b..61020516bcf 100644
--- a/app/views/projects/merge_requests/show/_commits.html.haml
+++ b/app/views/projects/merge_requests/show/_commits.html.haml
@@ -3,4 +3,4 @@
   Most recent commits displayed first
 
 %ol#commits-list.list-unstyled
-  = render "projects/commits/commits", project: @merge_request.project
+  = render "projects/commits/commits", project: @merge_request.source_project
diff --git a/spec/models/merge_request_spec.rb b/spec/models/merge_request_spec.rb
index 3155eff9ee1..1067ff7bb4d 100644
--- a/spec/models/merge_request_spec.rb
+++ b/spec/models/merge_request_spec.rb
@@ -1286,7 +1286,8 @@ describe MergeRequest, models: true do
         let(:project)      { create(:project) }
         let(:user)         { create(:user) }
         let(:fork_project) { create(:project, forked_from_project: project, namespace: user.namespace) }
-        let(:merge_request) do
+
+        let!(:merge_request) do
           create(:closed_merge_request,
             source_project: fork_project,
             target_project: project)
diff --git a/spec/views/projects/merge_requests/_commits.html.haml_spec.rb b/spec/views/projects/merge_requests/_commits.html.haml_spec.rb
new file mode 100644
index 00000000000..6f70b3daf8e
--- /dev/null
+++ b/spec/views/projects/merge_requests/_commits.html.haml_spec.rb
@@ -0,0 +1,38 @@
+require 'spec_helper'
+
+describe 'projects/merge_requests/show/_commits.html.haml' do
+  include Devise::Test::ControllerHelpers
+
+  let(:user) { create(:user) }
+  let(:target_project) { create(:project) }
+
+  let(:source_project) do
+    create(:project, forked_from_project: target_project)
+  end
+
+  let(:merge_request) do
+    create(:merge_request, :simple,
+      source_project: source_project,
+      target_project: target_project,
+      author: user)
+  end
+
+  before do
+    controller.prepend_view_path('app/views/projects')
+
+    assign(:merge_request, merge_request)
+    assign(:commits, merge_request.commits)
+  end
+
+  it 'shows commits from source project' do
+    render
+
+    commit = source_project.commit(merge_request.source_branch)
+    href = namespace_project_commit_path(
+      source_project.namespace,
+      source_project,
+      commit)
+
+    expect(rendered).to have_link(Commit.truncate_sha(commit.sha), href: href)
+  end
+end