Chore: homepage tests (#6278)

src/utils/contexts/tab.test.jsx

@@ -0,0 +1,33 @@
+// @vitest-environment jsdom
+
+import { fireEvent, render, screen } from "@testing-library/react";
+import { useContext } from "react";
+import { describe, expect, it } from "vitest";
+
+import { TabContext, TabProvider } from "./tab";
+
+function Reader() {
+  const { activeTab, setActiveTab } = useContext(TabContext);
+  return (
+    <div>
+      <div data-testid="value">{String(activeTab)}</div>
+      <button type="button" onClick={() => setActiveTab("next")}>
+        next
+      </button>
+    </div>
+  );
+}
+
+describe("utils/contexts/tab", () => {
+  it("provides initial tab and allows updates", () => {
+    render(
+      <TabProvider initialTab="first">
+        <Reader />
+      </TabProvider>,
+    );
+
+    expect(screen.getByTestId("value")).toHaveTextContent("first");
+    fireEvent.click(screen.getByRole("button", { name: "next" }));
+    expect(screen.getByTestId("value")).toHaveTextContent("next");
+  });
+});