1 files changed, 52 insertions, 0 deletions
diff --git a/spec/services/draft_notes/destroy_service_spec.rb b/spec/services/draft_notes/destroy_service_spec.rb
new file mode 100644
index 00000000000..d0bf88dcdbe
--- /dev/null
+++ b/spec/services/draft_notes/destroy_service_spec.rb
@@ -0,0 +1,52 @@
+# frozen_string_literal: true
+require 'spec_helper'
+
+describe DraftNotes::DestroyService do
+  let(:merge_request) { create(:merge_request) }
+  let(:project) { merge_request.target_project }
+  let(:user) { merge_request.author }
+
+  def destroy(draft_note = nil)
+    DraftNotes::DestroyService.new(merge_request, user).execute(draft_note)
+  end
+
+  it 'destroys a single draft note' do
+    drafts = create_list(:draft_note, 2, merge_request: merge_request, author: user)
+
+    expect { destroy(drafts.first) }
+      .to change { DraftNote.count }.by(-1)
+
+    expect(DraftNote.count).to eq(1)
+  end
+
+  it 'destroys all draft notes for a user in a merge request' do
+    create_list(:draft_note, 2, merge_request: merge_request, author: user)
+
+    expect { destroy }.to change { DraftNote.count }.by(-2)
+    expect(DraftNote.count).to eq(0)
+  end
+
+  context 'diff highlight cache clearing' do
+    context 'when destroying all draft notes of a user' do
+      it 'clears highlighting cache if unfold required for any' do
+        drafts = create_list(:draft_note, 2, merge_request: merge_request, author: user)
+
+        allow_any_instance_of(DraftNote).to receive_message_chain(:diff_file, :unfolded?) { true }
+        expect(merge_request).to receive_message_chain(:diffs, :clear_cache)
+
+        destroy(drafts.first)
+      end
+    end
+
+    context 'when destroying one draft note' do
+      it 'clears highlighting cache if unfold required' do
+        create_list(:draft_note, 2, merge_request: merge_request, author: user)
+
+        allow_any_instance_of(DraftNote).to receive_message_chain(:diff_file, :unfolded?) { true }
+        expect(merge_request).to receive_message_chain(:diffs, :clear_cache)
+
+        destroy
+      end
+    end
+  end
+end