1 files changed, 44 insertions, 0 deletions
diff --git a/spec/frontend/behaviors/load_startup_css_spec.js b/spec/frontend/behaviors/load_startup_css_spec.js
new file mode 100644
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+++ b/spec/frontend/behaviors/load_startup_css_spec.js
@@ -0,0 +1,44 @@
+import { setHTMLFixture } from 'helpers/fixtures';
+import { loadStartupCSS } from '~/behaviors/load_startup_css';
+
+describe('behaviors/load_startup_css', () => {
+  let loadListener;
+
+  const setupListeners = () => {
+    document
+      .querySelectorAll('link')
+      .forEach(x => x.addEventListener('load', () => loadListener(x)));
+  };
+
+  beforeEach(() => {
+    loadListener = jest.fn();
+
+    setHTMLFixture(`
+      <meta charset="utf-8" />
+      <link media="print" src="./lorem-print.css" />
+      <link media="print" src="./ipsum-print.css" />
+      <link media="all" src="./dolar-all.css" />
+    `);
+
+    setupListeners();
+
+    loadStartupCSS();
+  });
+
+  it('does nothing at first', () => {
+    expect(loadListener).not.toHaveBeenCalled();
+  });
+
+  describe('on window load', () => {
+    beforeEach(() => {
+      window.dispatchEvent(new Event('load'));
+    });
+
+    it('dispatches load to the print links', () => {
+      expect(loadListener.mock.calls.map(([el]) => el.getAttribute('src'))).toEqual([
+        './lorem-print.css',
+        './ipsum-print.css',
+      ]);
+    });
+  });
+});