Display related merge requests in commit detail page

4 files changed, 128 insertions, 0 deletions

diff --git a/spec/javascripts/commit_merge_requests_spec.js b/spec/javascripts/commit_merge_requests_spec.js
new file mode 100644
index 00000000000..3466ef51ea8
--- /dev/null
+++ b/spec/javascripts/commit_merge_requests_spec.js
@@ -0,0 +1,60 @@
+import * as CommitMergeRequests from '~/commit_merge_requests';
+
+describe('CommitMergeRequests', () => {
+  describe('createContent', () => {
+    it('should return created content', () => {
+      const content1 = CommitMergeRequests.createContent([{ iid: 1, path: '/path1', title: 'foo' }, { iid: 2, path: '/path2', title: 'baz' }])[0];
+      expect(content1.tagName).toEqual('SPAN');
+      expect(content1.childElementCount).toEqual(4);
+
+      const content2 = CommitMergeRequests.createContent([])[0];
+      expect(content2.tagName).toEqual('SPAN');
+      expect(content2.childElementCount).toEqual(0);
+      expect(content2.innerText).toEqual('No related merge requests found');
+    });
+  });
+
+  describe('getHeaderText', () => {
+    it('should return header text', () => {
+      expect(CommitMergeRequests.getHeaderText(0, 1)).toEqual('1 merge request');
+      expect(CommitMergeRequests.getHeaderText(0, 2)).toEqual('2 merge requests');
+      expect(CommitMergeRequests.getHeaderText(1, 1)).toEqual(',');
+      expect(CommitMergeRequests.getHeaderText(1, 2)).toEqual(',');
+    });
+  });
+
+  describe('createHeader', () => {
+    it('should return created header', () => {
+      const header = CommitMergeRequests.createHeader(0, 1)[0];
+      expect(header.tagName).toEqual('SPAN');
+      expect(header.innerText).toEqual('1 merge request');
+    });
+  });
+
+  describe('createItem', () => {
+    it('should return created item', () => {
+      const item = CommitMergeRequests.createItem({ iid: 1, path: '/path', title: 'foo' })[0];
+      expect(item.tagName).toEqual('SPAN');
+      expect(item.childElementCount).toEqual(2);
+      expect(item.children[0].tagName).toEqual('A');
+      expect(item.children[1].tagName).toEqual('SPAN');
+    });
+  });
+
+  describe('createLink', () => {
+    it('should return created link', () => {
+      const link = CommitMergeRequests.createLink({ iid: 1, path: '/path', title: 'foo' })[0];
+      expect(link.tagName).toEqual('A');
+      expect(link.href).toMatch(/\/path$/);
+      expect(link.innerText).toEqual('!1');
+    });
+  });
+
+  describe('createTitle', () => {
+    it('should return created title', () => {
+      const title = CommitMergeRequests.createTitle({ iid: 1, path: '/path', title: 'foo' })[0];
+      expect(title.tagName).toEqual('SPAN');
+      expect(title.innerText).toEqual('foo');
+    });
+  });
+});
diff --git a/spec/models/commit_spec.rb b/spec/models/commit_spec.rb
index 817254c7d1e..d3826417762 100644
--- a/spec/models/commit_spec.rb
+++ b/spec/models/commit_spec.rb
@@ -513,4 +513,17 @@ eos
       expect(described_class.valid_hash?('a' * 41)).to be false
     end
   end
+
+  describe '#merge_requests' do
+    let!(:project) { create(:project, :repository) }
+    let!(:merge_request1) { create(:merge_request, source_project: project, source_branch: 'master', target_branch: 'feature') }
+    let!(:merge_request2) { create(:merge_request, source_project: project, source_branch: 'merged-target', target_branch: 'feature') }
+    let(:commit1) { merge_request1.merge_request_diff.commits.last }
+    let(:commit2) { merge_request1.merge_request_diff.commits.first }
+
+    it 'returns merge_requests that introduced that commit' do
+      expect(commit1.merge_requests).to eq([merge_request1, merge_request2])
+      expect(commit2.merge_requests).to eq([merge_request1])
+    end
+  end
 end
diff --git a/spec/models/merge_request_diff_spec.rb b/spec/models/merge_request_diff_spec.rb
index d556004eccf..b4249d72fc8 100644
--- a/spec/models/merge_request_diff_spec.rb
+++ b/spec/models/merge_request_diff_spec.rb
@@ -15,6 +15,28 @@ describe MergeRequestDiff do
     it { expect(subject.start_commit_sha).to eq('0b4bc9a49b562e85de7cc9e834518ea6828729b9') }
   end
 
+  describe '.by_commit_sha' do
+    subject(:by_commit_sha) { described_class.by_commit_sha(sha) }
+
+    let!(:merge_request) { create(:merge_request, :with_diffs) }
+
+    context 'with sha contained in' do
+      let(:sha) { 'b83d6e391c22777fca1ed3012fce84f633d7fed0' }
+
+      it 'returns merge request diffs' do
+        expect(by_commit_sha).to eq([merge_request.merge_request_diff])
+      end
+    end
+
+    context 'with sha not contained in' do
+      let(:sha) { 'b83d6e3' }
+
+      it 'returns empty result' do
+        expect(by_commit_sha).to be_empty
+      end
+    end
+  end
+
   describe '#latest' do
     let!(:mr) { create(:merge_request, :with_diffs) }
     let!(:first_diff) { mr.merge_request_diff }
diff --git a/spec/models/merge_request_spec.rb b/spec/models/merge_request_spec.rb
index ceb06b3be18..c76f32b3989 100644
--- a/spec/models/merge_request_spec.rb
+++ b/spec/models/merge_request_spec.rb
@@ -87,6 +87,39 @@ describe MergeRequest do
     it { is_expected.to respond_to(:merge_when_pipeline_succeeds) }
   end
 
+  describe '.by_commit_sha' do
+    subject(:by_commit_sha) { described_class.by_commit_sha(sha) }
+
+    let!(:merge_request) { create(:merge_request, :with_diffs) }
+
+    context 'with sha contained in latest merge request diff' do
+      let(:sha) { 'b83d6e391c22777fca1ed3012fce84f633d7fed0' }
+
+      it 'returns merge requests' do
+        expect(by_commit_sha).to eq([merge_request])
+      end
+    end
+
+    context 'with sha contained not in latest merge request diff' do
+      let(:sha) { 'b83d6e391c22777fca1ed3012fce84f633d7fed0' }
+
+      it 'returns empty requests' do
+        latest_merge_request_diff = merge_request.merge_request_diffs.create
+        latest_merge_request_diff.merge_request_diff_commits.where(sha: 'b83d6e391c22777fca1ed3012fce84f633d7fed0').delete_all
+
+        expect(by_commit_sha).to be_empty
+      end
+    end
+
+    context 'with sha not contained in' do
+      let(:sha) { 'b83d6e3' }
+
+      it 'returns empty result' do
+        expect(by_commit_sha).to be_empty
+      end
+    end
+  end
+
   describe '.in_projects' do
     it 'returns the merge requests for a set of projects' do
       expect(described_class.in_projects(Project.all)).to eq([subject])