1 files changed, 36 insertions, 0 deletions
diff --git a/spec/helpers/webpack_helper_spec.rb b/spec/helpers/webpack_helper_spec.rb
new file mode 100644
index 00000000000..f9386c99dc3
--- /dev/null
+++ b/spec/helpers/webpack_helper_spec.rb
@@ -0,0 +1,36 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe WebpackHelper do
+  let(:source) { 'foo.js' }
+  let(:asset_path) { "/assets/webpack/#{source}" }
+
+  describe '#prefetch_link_tag' do
+    it 'returns prefetch link tag' do
+      expect(helper.prefetch_link_tag(source)).to eq("<link rel=\"prefetch\" href=\"/#{source}\">")
+    end
+  end
+
+  describe '#webpack_preload_asset_tag' do
+    before do
+      allow(Gitlab::Webpack::Manifest).to receive(:asset_paths).and_return([asset_path])
+    end
+
+    it 'preloads the resource by default' do
+      expect(helper).to receive(:preload_link_tag).with(asset_path, {}).and_call_original
+
+      output = helper.webpack_preload_asset_tag(source)
+
+      expect(output).to eq("<link rel=\"preload\" href=\"#{asset_path}\" as=\"script\" type=\"text/javascript\">")
+    end
+
+    it 'prefetches the resource if explicitly asked' do
+      expect(helper).to receive(:prefetch_link_tag).with(asset_path).and_call_original
+
+      output = helper.webpack_preload_asset_tag(source, prefetch: true)
+
+      expect(output).to eq("<link rel=\"prefetch\" href=\"#{asset_path}\">")
+    end
+  end
+end