Enables Run Pipeline button to be rendered

In the Merge Request view, under pipelines tab
the user can see a run pipeline button

Adds axios post request to button click

Adds the logic to handle the user click,
refresh the table and disable the button while thee
request is being made

Updates UI for desktop and mobile

Adds specs
Regenerates potfile

Follow-up after review

Uses .finally to avoid code repetition

1 files changed, 64 insertions, 0 deletions

diff --git a/spec/requests/api/merge_requests_spec.rb b/spec/requests/api/merge_requests_spec.rb
index 15d6db42760..8179da2f97c 100644
--- a/spec/requests/api/merge_requests_spec.rb
+++ b/spec/requests/api/merge_requests_spec.rb
@@ -1033,6 +1033,70 @@ describe API::MergeRequests do
     end
   end
 
+  describe 'POST /projects/:id/merge_requests/:merge_request_iid/pipelines' do
+    before do
+      allow_any_instance_of(Ci::Pipeline)
+        .to receive(:ci_yaml_file)
+        .and_return(YAML.dump({
+          rspec: {
+            script: 'ls',
+            only: ['merge_requests']
+          }
+        }))
+    end
+
+    let(:project) do
+      create(:project, :private, :repository,
+        creator: user,
+        namespace: user.namespace,
+        only_allow_merge_if_pipeline_succeeds: false)
+    end
+
+    let(:merge_request) do
+      create(:merge_request, :with_detached_merge_request_pipeline,
+        milestone: milestone1,
+        author: user,
+        assignees: [user],
+        source_project: project,
+        target_project: project,
+        title: 'Test',
+        created_at: base_time)
+    end
+
+    let(:merge_request_iid)  { merge_request.iid }
+    let(:authenticated_user) { user }
+
+    let(:request) do
+      post api("/projects/#{project.id}/merge_requests/#{merge_request_iid}/pipelines", authenticated_user)
+    end
+
+    context 'when authorized' do
+      it 'creates and returns the new Pipeline' do
+        expect { request }.to change(Ci::Pipeline, :count).by(1)
+        expect(response).to have_gitlab_http_status(200)
+        expect(json_response).to be_a Hash
+      end
+    end
+
+    context 'when unauthorized' do
+      let(:authenticated_user) { create(:user) }
+
+      it 'responds with a blank 404' do
+        expect { request }.not_to change(Ci::Pipeline, :count)
+        expect(response).to have_gitlab_http_status(404)
+      end
+    end
+
+    context 'when the merge request does not exist' do
+      let(:merge_request_iid) { 777 }
+
+      it 'responds with a blank 404' do
+        expect { request }.not_to change(Ci::Pipeline, :count)
+        expect(response).to have_gitlab_http_status(404)
+      end
+    end
+  end
+
   describe 'POST /projects/:id/merge_requests' do
     context 'support for deprecated assignee_id' do
       let(:params) do