Add latest changes from gitlab-org/gitlab@14-1-stable-eev14.1.0-rc42

2 files changed, 265 insertions, 0 deletions

diff --git a/spec/requests/projects/merge_requests/diffs_spec.rb b/spec/requests/projects/merge_requests/diffs_spec.rb
new file mode 100644
index 00000000000..3a64c88acc1
--- /dev/null
+++ b/spec/requests/projects/merge_requests/diffs_spec.rb
@@ -0,0 +1,126 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe 'Merge Requests Diffs' do
+  let_it_be(:project) { create(:project, :repository) }
+  let_it_be(:user) { create(:user) }
+  let_it_be(:merge_request) { create(:merge_request_with_diffs, target_project: project, source_project: project) }
+
+  before do
+    project.add_maintainer(user)
+    sign_in(user)
+  end
+
+  describe 'GET diffs_batch' do
+    let(:headers) { {} }
+
+    shared_examples_for 'serializes diffs with expected arguments' do
+      it 'serializes paginated merge request diff collection' do
+        expect_next_instance_of(PaginatedDiffSerializer) do |instance|
+          expect(instance).to receive(:represent)
+            .with(an_instance_of(collection), expected_options)
+            .and_call_original
+        end
+
+        subject
+      end
+    end
+
+    def collection_arguments(pagination_data = {})
+      {
+        environment: nil,
+        merge_request: merge_request,
+        diff_view: :inline,
+        merge_ref_head_diff: nil,
+        pagination_data: {
+          total_pages: nil
+        }.merge(pagination_data)
+      }
+    end
+
+    def go(extra_params = {})
+      params = {
+        namespace_id: project.namespace.to_param,
+        project_id: project,
+        id: merge_request.iid,
+        page: 0,
+        per_page: 20,
+        format: 'json'
+      }
+
+      get diffs_batch_namespace_project_json_merge_request_path(params.merge(extra_params)), headers: headers
+    end
+
+    context 'with caching', :use_clean_rails_memory_store_caching do
+      subject { go(page: 0, per_page: 5) }
+
+      context 'when the request has not been cached' do
+        it_behaves_like 'serializes diffs with expected arguments' do
+          let(:collection) { Gitlab::Diff::FileCollection::MergeRequestDiffBatch }
+          let(:expected_options) { collection_arguments(total_pages: 20) }
+        end
+      end
+
+      context 'when the request has already been cached' do
+        before do
+          go(page: 0, per_page: 5)
+        end
+
+        it 'does not serialize diffs' do
+          expect_next_instance_of(PaginatedDiffSerializer) do |instance|
+            expect(instance).not_to receive(:represent)
+          end
+
+          subject
+        end
+
+        context 'with the different pagination option' do
+          subject { go(page: 5, per_page: 5) }
+
+          it_behaves_like 'serializes diffs with expected arguments' do
+            let(:collection) { Gitlab::Diff::FileCollection::MergeRequestDiffBatch }
+            let(:expected_options) { collection_arguments(total_pages: 20) }
+          end
+        end
+
+        context 'with the different diff_view' do
+          subject { go(page: 0, per_page: 5, view: :parallel) }
+
+          it_behaves_like 'serializes diffs with expected arguments' do
+            let(:collection) { Gitlab::Diff::FileCollection::MergeRequestDiffBatch }
+            let(:expected_options) { collection_arguments(total_pages: 20).merge(diff_view: :parallel) }
+          end
+        end
+
+        context 'with the different expanded option' do
+          subject { go(page: 0, per_page: 5, expanded: true ) }
+
+          it_behaves_like 'serializes diffs with expected arguments' do
+            let(:collection) { Gitlab::Diff::FileCollection::MergeRequestDiffBatch }
+            let(:expected_options) { collection_arguments(total_pages: 20) }
+          end
+        end
+
+        context 'with the different ignore_whitespace_change option' do
+          subject { go(page: 0, per_page: 5, w: 1) }
+
+          it_behaves_like 'serializes diffs with expected arguments' do
+            let(:collection) { Gitlab::Diff::FileCollection::Compare }
+            let(:expected_options) { collection_arguments(total_pages: 20) }
+          end
+        end
+      end
+
+      context 'when the paths is given' do
+        subject { go(page: 0, per_page: 5, paths: %w[README CHANGELOG]) }
+
+        it 'does not use cache' do
+          expect(Rails.cache).not_to receive(:fetch).with(/cache:gitlab:PaginatedDiffSerializer/).and_call_original
+
+          subject
+        end
+      end
+    end
+  end
+end
diff --git a/spec/requests/projects/merge_requests_discussions_spec.rb b/spec/requests/projects/merge_requests_discussions_spec.rb
index eb8cf9f797d..595222a9eb2 100644
--- a/spec/requests/projects/merge_requests_discussions_spec.rb
+++ b/spec/requests/projects/merge_requests_discussions_spec.rb
@@ -52,5 +52,144 @@ RSpec.describe 'merge requests discussions' do
       expect { send_request }
         .to change { Gitlab::GitalyClient.get_request_count }.by_at_most(4)
     end
+
+    context 'caching', :use_clean_rails_memory_store_caching do
+      let!(:first_note) { create(:diff_note_on_merge_request, noteable: merge_request, project: project) }
+      let!(:second_note) { create(:diff_note_on_merge_request, in_reply_to: first_note, noteable: merge_request, project: project) }
+      let!(:award_emoji) { create(:award_emoji, awardable: first_note) }
+
+      before do
+        # Make a request to cache the discussions
+        send_request
+      end
+
+      shared_examples 'cache miss' do
+        it 'does not hit a warm cache' do
+          expect_next_instance_of(DiscussionSerializer) do |serializer|
+            expect(serializer).to receive(:represent) do |arg|
+              expect(arg.notes).to contain_exactly(*changed_notes)
+            end.and_call_original
+          end
+
+          send_request
+        end
+      end
+
+      it 'gets cached on subsequent requests' do
+        expect_next_instance_of(DiscussionSerializer) do |serializer|
+          expect(serializer).not_to receive(:represent)
+        end
+
+        send_request
+      end
+
+      context 'when a note in a discussion got updated' do
+        before do
+          first_note.update!(updated_at: 1.minute.from_now)
+        end
+
+        it_behaves_like 'cache miss' do
+          let(:changed_notes) { [first_note, second_note] }
+        end
+      end
+
+      context 'when a note in a discussion got resolved' do
+        before do
+          travel_to(1.minute.from_now) do
+            first_note.resolve!(user)
+          end
+        end
+
+        it_behaves_like 'cache miss' do
+          let(:changed_notes) { [first_note, second_note] }
+        end
+      end
+
+      context 'when a note is added to a discussion' do
+        let!(:third_note) { create(:diff_note_on_merge_request, in_reply_to: first_note, noteable: merge_request, project: project) }
+
+        it_behaves_like 'cache miss' do
+          let(:changed_notes) { [first_note, second_note, third_note] }
+        end
+      end
+
+      context 'when a note is removed from a discussion' do
+        before do
+          second_note.destroy!
+        end
+
+        it_behaves_like 'cache miss' do
+          let(:changed_notes) { [first_note] }
+        end
+      end
+
+      context 'when an emoji is awarded to a note in discussion' do
+        before do
+          travel_to(1.minute.from_now) do
+            create(:award_emoji, awardable: first_note)
+          end
+        end
+
+        it_behaves_like 'cache miss' do
+          let(:changed_notes) { [first_note, second_note] }
+        end
+      end
+
+      context 'when an award emoji is removed from a note in discussion' do
+        before do
+          travel_to(1.minute.from_now) do
+            award_emoji.destroy!
+          end
+        end
+
+        it_behaves_like 'cache miss' do
+          let(:changed_notes) { [first_note, second_note] }
+        end
+      end
+
+      context 'when cached markdown version gets bump' do
+        before do
+          settings = Gitlab::CurrentSettings.current_application_settings
+          settings.update!(local_markdown_version: settings.local_markdown_version + 1)
+        end
+
+        it_behaves_like 'cache miss' do
+          let(:changed_notes) { [first_note, second_note] }
+        end
+      end
+
+      context 'when the diff note position changes' do
+        before do
+          # This replicates a position change wherein timestamps aren't updated
+          # which is why `Gitlab::Timeless.timeless` is utilized. This is the
+          # same approach being used in Discussions::UpdateDiffPositionService
+          # which is responsible for updating the positions of diff discussions
+          # when MR updates.
+          first_note.position = Gitlab::Diff::Position.new(
+            old_path: first_note.position.old_path,
+            new_path: first_note.position.new_path,
+            old_line: first_note.position.old_line,
+            new_line: first_note.position.new_line + 1,
+            diff_refs: first_note.position.diff_refs
+          )
+
+          Gitlab::Timeless.timeless(first_note, &:save)
+        end
+
+        it_behaves_like 'cache miss' do
+          let(:changed_notes) { [first_note, second_note] }
+        end
+      end
+
+      context 'when merge_request_discussion_cache is disabled' do
+        before do
+          stub_feature_flags(merge_request_discussion_cache: false)
+        end
+
+        it_behaves_like 'cache miss' do
+          let(:changed_notes) { [first_note, second_note] }
+        end
+      end
+    end
   end
 end