1 files changed, 184 insertions, 0 deletions
diff --git a/spec/services/issue_links/create_service_spec.rb b/spec/services/issue_links/create_service_spec.rb
new file mode 100644
index 00000000000..873890d25cf
--- /dev/null
+++ b/spec/services/issue_links/create_service_spec.rb
@@ -0,0 +1,184 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe IssueLinks::CreateService do
+  describe '#execute' do
+    let(:namespace) { create :namespace }
+    let(:project) { create :project, namespace: namespace }
+    let(:issue) { create :issue, project: project }
+    let(:user) { create :user }
+    let(:params) do
+      {}
+    end
+
+    before do
+      project.add_developer(user)
+    end
+
+    subject { described_class.new(issue, user, params).execute }
+
+    context 'when the reference list is empty' do
+      let(:params) do
+        { issuable_references: [] }
+      end
+
+      it 'returns error' do
+        is_expected.to eq(message: 'No Issue found for given params', status: :error, http_status: 404)
+      end
+    end
+
+    context 'when Issue not found' do
+      let(:params) do
+        { issuable_references: ["##{non_existing_record_iid}"] }
+      end
+
+      it 'returns error' do
+        is_expected.to eq(message: 'No Issue found for given params', status: :error, http_status: 404)
+      end
+
+      it 'no relationship is created' do
+        expect { subject }.not_to change(IssueLink, :count)
+      end
+    end
+
+    context 'when user has no permission to target project Issue' do
+      let(:target_issuable) { create :issue }
+
+      let(:params) do
+        { issuable_references: [target_issuable.to_reference(project)] }
+      end
+
+      it 'returns error' do
+        target_issuable.project.add_guest(user)
+
+        is_expected.to eq(message: 'No Issue found for given params', status: :error, http_status: 404)
+      end
+
+      it 'no relationship is created' do
+        expect { subject }.not_to change(IssueLink, :count)
+      end
+    end
+
+    context 'source and target are the same issue' do
+      let(:params) do
+        { issuable_references: [issue.to_reference] }
+      end
+
+      it 'does not create notes' do
+        expect(SystemNoteService).not_to receive(:relate_issue)
+
+        subject
+      end
+
+      it 'no relationship is created' do
+        expect { subject }.not_to change(IssueLink, :count)
+      end
+    end
+
+    context 'when there is an issue to relate' do
+      let(:issue_a) { create :issue, project: project }
+      let(:another_project) { create :project, namespace: project.namespace }
+      let(:another_project_issue) { create :issue, project: another_project }
+
+      let(:issue_a_ref) { issue_a.to_reference }
+      let(:another_project_issue_ref) { another_project_issue.to_reference(project) }
+
+      let(:params) do
+        { issuable_references: [issue_a_ref, another_project_issue_ref] }
+      end
+
+      before do
+        another_project.add_developer(user)
+      end
+
+      it 'creates relationships' do
+        expect { subject }.to change(IssueLink, :count).from(0).to(2)
+
+        expect(IssueLink.find_by!(target: issue_a)).to have_attributes(source: issue, link_type: 'relates_to')
+        expect(IssueLink.find_by!(target: another_project_issue)).to have_attributes(source: issue, link_type: 'relates_to')
+      end
+
+      it 'returns success status' do
+        is_expected.to eq(status: :success)
+      end
+
+      it 'creates notes' do
+        # First two-way relation notes
+        expect(SystemNoteService).to receive(:relate_issue)
+          .with(issue, issue_a, user)
+        expect(SystemNoteService).to receive(:relate_issue)
+          .with(issue_a, issue, user)
+
+        # Second two-way relation notes
+        expect(SystemNoteService).to receive(:relate_issue)
+          .with(issue, another_project_issue, user)
+        expect(SystemNoteService).to receive(:relate_issue)
+          .with(another_project_issue, issue, user)
+
+        subject
+      end
+
+      context 'issue is an incident' do
+        let(:issue) { create(:incident, project: project) }
+
+        it_behaves_like 'an incident management tracked event', :incident_management_incident_relate do
+          let(:current_user) { user }
+        end
+      end
+    end
+
+    context 'when reference of any already related issue is present' do
+      let(:issue_a) { create :issue, project: project }
+      let(:issue_b) { create :issue, project: project }
+      let(:issue_c) { create :issue, project: project }
+
+      before do
+        create :issue_link, source: issue, target: issue_b, link_type: IssueLink::TYPE_RELATES_TO
+        create :issue_link, source: issue, target: issue_c, link_type: IssueLink::TYPE_RELATES_TO
+      end
+
+      let(:params) do
+        {
+          issuable_references: [
+            issue_a.to_reference,
+            issue_b.to_reference,
+            issue_c.to_reference
+          ],
+          link_type: IssueLink::TYPE_RELATES_TO
+        }
+      end
+
+      it 'creates notes only for new relations' do
+        expect(SystemNoteService).to receive(:relate_issue).with(issue, issue_a, anything)
+        expect(SystemNoteService).to receive(:relate_issue).with(issue_a, issue, anything)
+        expect(SystemNoteService).not_to receive(:relate_issue).with(issue, issue_b, anything)
+        expect(SystemNoteService).not_to receive(:relate_issue).with(issue_b, issue, anything)
+        expect(SystemNoteService).not_to receive(:relate_issue).with(issue, issue_c, anything)
+        expect(SystemNoteService).not_to receive(:relate_issue).with(issue_c, issue, anything)
+
+        subject
+      end
+    end
+
+    context 'when there are invalid references' do
+      let(:issue_a) { create :issue, project: project }
+
+      let(:params) do
+        { issuable_references: [issue.to_reference, issue_a.to_reference] }
+      end
+
+      it 'creates links only for valid references' do
+        expect { subject }.to change { IssueLink.count }.by(1)
+      end
+
+      it 'returns error status' do
+        expect(subject).to eq(
+          status: :error,
+          http_status: 422,
+          message: "#{issue.to_reference} cannot be added: cannot be related to itself"
+        )
+      end
+    end
+  end
+end