Chore: homepage tests (#6278)

src/components/widgets/resources/cpu.test.jsx

@@ -0,0 +1,55 @@
+// @vitest-environment jsdom
+
+import { render } from "@testing-library/react";
+import { beforeEach, describe, expect, it, vi } from "vitest";
+
+const { useSWR, Resource, Error } = vi.hoisted(() => ({
+  useSWR: vi.fn(),
+  Resource: vi.fn(() => <div data-testid="resource" />),
+  Error: vi.fn(() => <div data-testid="error" />),
+}));
+
+vi.mock("swr", () => ({ default: useSWR }));
+vi.mock("../widget/resource", () => ({ default: Resource }));
+vi.mock("../widget/error", () => ({ default: Error }));
+
+import Cpu from "./cpu";
+
+describe("components/widgets/resources/cpu", () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+  });
+
+  it("renders a placeholder Resource while loading", () => {
+    useSWR.mockReturnValue({ data: undefined, error: undefined });
+
+    render(<Cpu expanded refresh={1000} />);
+
+    expect(Resource).toHaveBeenCalled();
+    const props = Resource.mock.calls[0][0];
+    expect(props.value).toBe("-");
+    expect(props.expanded).toBe(true);
+  });
+
+  it("renders usage/load values when data is present", () => {
+    useSWR.mockReturnValue({
+      data: { cpu: { usage: 12.3, load: 1.23 } },
+      error: undefined,
+    });
+
+    render(<Cpu expanded={false} />);
+
+    const props = Resource.mock.calls[0][0];
+    expect(props.value).toBe("12.3");
+    expect(props.expandedValue).toBe("1.23");
+    expect(props.percentage).toBe(12.3);
+  });
+
+  it("renders Error when SWR errors", () => {
+    useSWR.mockReturnValue({ data: undefined, error: new Error("nope") });
+
+    render(<Cpu expanded />);
+
+    expect(Error).toHaveBeenCalled();
+  });
+});