Check if file has been modified for each action provided.

When commiting multiple files we're now checking if any of those files
has been modified by another commit and we're rejecting the new commit
in this case.

1 files changed, 43 insertions, 2 deletions

diff --git a/spec/services/files/multi_service_spec.rb b/spec/services/files/multi_service_spec.rb
index 34457ee796a..6e11f126f14 100644
--- a/spec/services/files/multi_service_spec.rb
+++ b/spec/services/files/multi_service_spec.rb
@@ -6,14 +6,20 @@ describe Files::MultiService do
   let(:project) { create(:project, :repository) }
   let(:user) { create(:user) }
   let(:branch_name) { project.default_branch }
+  let(:file_path) { 'files/ruby/popen.rb' }
   let(:action) { 'update' }
 
+  let!(:original_commit_id) do
+    Gitlab::Git::Commit.last_for_path(project.repository, branch_name, file_path).sha
+  end
+
   let(:actions) do
     [
       {
         action: action,
-        file_path: 'files/ruby/popen.rb',
-        content: 'New content'
+        file_path: file_path,
+        content: 'New content',
+        last_commit_id: original_commit_id
       }
     ]
   end
@@ -50,5 +56,40 @@ describe Files::MultiService do
         expect(results[:message]).to match(/Unknown action/)
       end
     end
+
+    describe 'Updating files' do
+      context 'when the file has been previously updated' do
+        before do
+          update_file(file_path)
+        end
+
+        it 'rejects the commit' do
+          results = subject.execute
+
+          expect(results[:status]).to eq(:error)
+          expect(results[:message]).to match(file_path)
+        end
+      end
+
+      context 'when the file have not been modified' do
+        it 'accepts the commit' do
+          results = subject.execute
+
+          expect(results[:status]).to eq(:success)
+        end
+      end
+    end
+  end
+
+  def update_file(path)
+    params = {
+      file_path: path,
+      start_branch: branch_name,
+      branch_name: branch_name,
+      commit_message: 'Update file',
+      file_content: 'New content'
+    }
+
+    Files::UpdateService.new(project, user, params).execute
   end
 end