테스트 커버리지 보강 및 공통 유틸 테스트 추가

devfront/src/components/ui/copy-button.test.tsx

@@ -0,0 +1,82 @@
+import { act } from "react";
+import { createRoot, type Root } from "react-dom/client";
+import { afterEach, describe, expect, it, vi } from "vitest";
+import { CopyButton } from "./copy-button";
+
+const roots: Root[] = [];
+
+afterEach(() => {
+  for (const root of roots.splice(0)) {
+    act(() => {
+      root.unmount();
+    });
+  }
+  vi.restoreAllMocks();
+  delete (navigator as Navigator & { clipboard?: unknown }).clipboard;
+  Object.defineProperty(window, "isSecureContext", {
+    value: false,
+    configurable: true,
+  });
+  document.body.innerHTML = "";
+});
+
+function renderCopyButton(value: string, onCopy = vi.fn()) {
+  const container = document.createElement("div");
+  document.body.appendChild(container);
+  const root = createRoot(container);
+  roots.push(root);
+
+  act(() => {
+    root.render(<CopyButton value={value} onCopy={onCopy} />);
+  });
+
+  return { container, onCopy };
+}
+
+describe("CopyButton", () => {
+  it("copies with the clipboard API when secure context is available", async () => {
+    const writeText = vi.fn().mockResolvedValue(undefined);
+    Object.defineProperty(navigator, "clipboard", {
+      value: { writeText },
+      configurable: true,
+    });
+    Object.defineProperty(window, "isSecureContext", {
+      value: true,
+      configurable: true,
+    });
+
+    const { container, onCopy } = renderCopyButton("client-secret");
+    const button = container.querySelector("button");
+    expect(button).not.toBeNull();
+
+    await act(async () => {
+      button?.dispatchEvent(new MouseEvent("click", { bubbles: true }));
+    });
+
+    expect(writeText).toHaveBeenCalledWith("client-secret");
+    expect(onCopy).toHaveBeenCalledTimes(1);
+  });
+
+  it("falls back to execCommand when clipboard API is unavailable", async () => {
+    const execCommand = vi.fn(() => true);
+    Object.defineProperty(document, "execCommand", {
+      value: execCommand,
+      configurable: true,
+    });
+    Object.defineProperty(window, "isSecureContext", {
+      value: false,
+      configurable: true,
+    });
+
+    const { container, onCopy } = renderCopyButton("client-secret");
+    const button = container.querySelector("button");
+    expect(button).not.toBeNull();
+
+    await act(async () => {
+      button?.dispatchEvent(new MouseEvent("click", { bubbles: true }));
+    });
+
+    expect(execCommand).toHaveBeenCalledWith("copy");
+    expect(onCopy).toHaveBeenCalledTimes(1);
+  });
+});