1 files changed, 86 insertions, 0 deletions
diff --git a/spec/models/diff_discussion_spec.rb b/spec/models/diff_discussion_spec.rb
new file mode 100644
index 00000000000..81f338745b1
--- /dev/null
+++ b/spec/models/diff_discussion_spec.rb
@@ -0,0 +1,86 @@
+require 'spec_helper'
+
+describe DiffDiscussion, model: true do
+  include RepoHelpers
+
+  subject { described_class.new([diff_note]) }
+
+  let(:project) { create(:project) }
+  let(:merge_request) { create(:merge_request, source_project: project, target_project: project) }
+  let(:diff_note) { create(:diff_note_on_merge_request, noteable: merge_request, project: project) }
+
+  describe '#reply_attributes' do
+    it 'includes position and original_position' do
+      attributes = subject.reply_attributes
+      expect(attributes[:position]).to eq(diff_note.position.to_json)
+      expect(attributes[:original_position]).to eq(diff_note.original_position.to_json)
+    end
+  end
+
+  describe '#merge_request_version_params' do
+    let(:merge_request) { create(:merge_request, source_project: project, target_project: project, importing: true) }
+    let!(:merge_request_diff1) { merge_request.merge_request_diffs.create(head_commit_sha: '6f6d7e7ed97bb5f0054f2b1df789b39ca89b6ff9') }
+    let!(:merge_request_diff2) { merge_request.merge_request_diffs.create(head_commit_sha: nil) }
+    let!(:merge_request_diff3) { merge_request.merge_request_diffs.create(head_commit_sha: '5937ac0a7beb003549fc5fd26fc247adbce4a52e') }
+
+    context 'when the discussion is active' do
+      it 'returns an empty hash, which will end up showing the latest version' do
+        expect(subject.merge_request_version_params).to eq({})
+      end
+    end
+
+    context 'when the discussion is on an older merge request version' do
+      let(:position) do
+        Gitlab::Diff::Position.new(
+          old_path: ".gitmodules",
+          new_path: ".gitmodules",
+          old_line: nil,
+          new_line: 4,
+          diff_refs: merge_request_diff1.diff_refs
+        )
+      end
+
+      let(:diff_note) { create(:diff_note_on_merge_request, noteable: merge_request, project: project, position: position) }
+
+      before do
+        diff_note.position = diff_note.original_position
+        diff_note.save!
+      end
+
+      it 'returns the diff ID for the version to show' do
+        expect(diff_id: merge_request_diff1.id)
+      end
+    end
+
+    context 'when the discussion is on a comparison between merge request versions' do
+      let(:position) do
+        Gitlab::Diff::Position.new(
+          old_path: ".gitmodules",
+          new_path: ".gitmodules",
+          old_line: 4,
+          new_line: 4,
+          diff_refs: merge_request_diff3.compare_with(merge_request_diff1.head_commit_sha).diff_refs
+        )
+      end
+
+      let(:diff_note) { create(:diff_note_on_merge_request, noteable: merge_request, project: project, position: position) }
+
+      it 'returns the diff ID and start sha of the versions to compare' do
+        expect(subject.merge_request_version_params).to eq(diff_id: merge_request_diff3.id, start_sha: merge_request_diff1.head_commit_sha)
+      end
+    end
+
+    context 'when the discussion does not have a merge request version' do
+      let(:diff_note) { create(:diff_note_on_merge_request, noteable: merge_request, project: project, diff_refs: project.commit(sample_commit.id).diff_refs) }
+
+      before do
+        diff_note.position = diff_note.original_position
+        diff_note.save!
+      end
+
+      it 'returns nil' do
+        expect(subject.merge_request_version_params).to be_nil
+      end
+    end
+  end
+end