Added relationships between Release and Milestone

Modified schema via migrations.
Added one-to-one relationship between the two models.
Added changelog file

1 files changed, 36 insertions, 0 deletions

diff --git a/spec/models/milestone_release_spec.rb b/spec/models/milestone_release_spec.rb
new file mode 100644
index 00000000000..d6f73275977
--- /dev/null
+++ b/spec/models/milestone_release_spec.rb
@@ -0,0 +1,36 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe MilestoneRelease do
+  let(:project) { create(:project) }
+  let(:release) { create(:release, project: project) }
+  let(:milestone) { create(:milestone, project: project) }
+
+  subject { build(:milestone_release, release: release, milestone: milestone) }
+
+  describe 'associations' do
+    it { is_expected.to belong_to(:milestone) }
+    it { is_expected.to belong_to(:release) }
+  end
+
+  describe 'validations' do
+    it { is_expected.to validate_uniqueness_of(:milestone_id).scoped_to(:release_id) }
+
+    context 'when milestone and release do not have the same project' do
+      it 'is not valid' do
+        other_project = create(:project)
+        release = build(:release, project: other_project)
+        milestone_release = described_class.new(milestone: milestone, release: release)
+        expect(milestone_release).not_to be_valid
+      end
+    end
+
+    context 'when milestone and release have the same project' do
+      it 'is valid' do
+        milestone_release = described_class.new(milestone: milestone, release: release)
+        expect(milestone_release).to be_valid
+      end
+    end
+  end
+end