1 files changed, 57 insertions, 0 deletions
diff --git a/spec/lib/gitlab/github_import/milestone_finder_spec.rb b/spec/lib/gitlab/github_import/milestone_finder_spec.rb
new file mode 100644
index 00000000000..dff931a2fe8
--- /dev/null
+++ b/spec/lib/gitlab/github_import/milestone_finder_spec.rb
@@ -0,0 +1,57 @@
+require 'spec_helper'
+
+describe Gitlab::GithubImport::MilestoneFinder, :clean_gitlab_redis_cache do
+  let!(:project) { create(:project) }
+  let!(:milestone) { create(:milestone, project: project) }
+  let(:finder) { described_class.new(project) }
+
+  describe '#id_for' do
+    let(:issuable) { double(:issuable, milestone_number: milestone.iid) }
+
+    context 'with a cache in place' do
+      before do
+        finder.build_cache
+      end
+
+      it 'returns the milestone ID of the given issuable' do
+        expect(finder.id_for(issuable)).to eq(milestone.id)
+      end
+
+      it 'returns nil for an empty cache key' do
+        key = finder.cache_key_for(milestone.iid)
+
+        Gitlab::GithubImport::Caching.write(key, '')
+
+        expect(finder.id_for(issuable)).to be_nil
+      end
+
+      it 'returns nil for an issuable with a non-existing milestone' do
+        expect(finder.id_for(double(:issuable, milestone_number: 5))).to be_nil
+      end
+    end
+
+    context 'without a cache in place' do
+      it 'returns nil' do
+        expect(finder.id_for(issuable)).to be_nil
+      end
+    end
+  end
+
+  describe '#build_cache' do
+    it 'builds the cache of all project milestones' do
+      expect(Gitlab::GithubImport::Caching)
+        .to receive(:write_multiple)
+        .with("github-import/milestone-finder/#{project.id}/1" => milestone.id)
+        .and_call_original
+
+      finder.build_cache
+    end
+  end
+
+  describe '#cache_key_for' do
+    it 'returns the cache key for an IID' do
+      expect(finder.cache_key_for(10))
+        .to eq("github-import/milestone-finder/#{project.id}/10")
+    end
+  end
+end