1 files changed, 101 insertions, 0 deletions
diff --git a/spec/support/shared_examples/lib/cache_helpers_shared_examples.rb b/spec/support/shared_examples/lib/cache_helpers_shared_examples.rb
new file mode 100644
index 00000000000..845fa78a827
--- /dev/null
+++ b/spec/support/shared_examples/lib/cache_helpers_shared_examples.rb
@@ -0,0 +1,101 @@
+# frozen_string_literal: true
+
+RSpec.shared_examples_for 'object cache helper' do
+  it { is_expected.to be_a(Gitlab::Json::PrecompiledJson) }
+
+  it "uses the presenter" do
+    expect(presenter).to receive(:represent).with(presentable, project: project)
+
+    subject
+  end
+
+  it "is valid JSON" do
+    parsed = Gitlab::Json.parse(subject.to_s)
+
+    expect(parsed).to be_a(Hash)
+    expect(parsed["id"]).to eq(presentable.id)
+  end
+
+  it "fetches from the cache" do
+    expect(instance.cache).to receive(:fetch).with("#{presenter.class.name}:#{presentable.cache_key}:#{user.cache_key}", expires_in: described_class::DEFAULT_EXPIRY).once
+
+    subject
+  end
+
+  context "when a cache context is supplied" do
+    before do
+      kwargs[:cache_context] = -> (item) { item.project.cache_key }
+    end
+
+    it "uses the context to augment the cache key" do
+      expect(instance.cache).to receive(:fetch).with("#{presenter.class.name}:#{presentable.cache_key}:#{project.cache_key}", expires_in: described_class::DEFAULT_EXPIRY).once
+
+      subject
+    end
+  end
+
+  context "when expires_in is supplied" do
+    it "sets the expiry when accessing the cache" do
+      kwargs[:expires_in] = 7.days
+
+      expect(instance.cache).to receive(:fetch).with("#{presenter.class.name}:#{presentable.cache_key}:#{user.cache_key}", expires_in: 7.days).once
+
+      subject
+    end
+  end
+end
+
+RSpec.shared_examples_for 'collection cache helper' do
+  it { is_expected.to be_an(Gitlab::Json::PrecompiledJson) }
+
+  it "uses the presenter" do
+    presentable.each do |item|
+      expect(presenter).to receive(:represent).with(item, project: project)
+    end
+
+    subject
+  end
+
+  it "is valid JSON" do
+    parsed = Gitlab::Json.parse(subject.to_s)
+
+    expect(parsed).to be_an(Array)
+
+    presentable.each_with_index do |item, i|
+      expect(parsed[i]["id"]).to eq(item.id)
+    end
+  end
+
+  it "fetches from the cache" do
+    keys = presentable.map { |item| "#{presenter.class.name}:#{item.cache_key}:#{user.cache_key}" }
+
+    expect(instance.cache).to receive(:fetch_multi).with(*keys, expires_in: described_class::DEFAULT_EXPIRY).once.and_call_original
+
+    subject
+  end
+
+  context "when a cache context is supplied" do
+    before do
+      kwargs[:cache_context] = -> (item) { item.project.cache_key }
+    end
+
+    it "uses the context to augment the cache key" do
+      keys = presentable.map { |item| "#{presenter.class.name}:#{item.cache_key}:#{project.cache_key}" }
+
+      expect(instance.cache).to receive(:fetch_multi).with(*keys, expires_in: described_class::DEFAULT_EXPIRY).once.and_call_original
+
+      subject
+    end
+  end
+
+  context "expires_in is supplied" do
+    it "sets the expiry when accessing the cache" do
+      keys = presentable.map { |item| "#{presenter.class.name}:#{item.cache_key}:#{user.cache_key}" }
+      kwargs[:expires_in] = 7.days
+
+      expect(instance.cache).to receive(:fetch_multi).with(*keys, expires_in: 7.days).once.and_call_original
+
+      subject
+    end
+  end
+end