test(copy-button): add unit tests

tests/CopyButton.test.svelte

@@ -1,11 +0,0 @@
-<script lang="ts">
-  import { CopyButton } from "carbon-components-svelte";
-</script>
-
-<CopyButton
-  text="text"
-  on:click
-  on:copy
-  copy={(text) => text}
-  feedback="Copied to clipboard"
-/>

tests/CopyButton/CopyButton.test.svelte

@@ -0,0 +1,26 @@
+<script lang="ts">
+  import { CopyButton } from "carbon-components-svelte";
+</script>
+
+<CopyButton
+  text="text"
+  iconDescription="Basic"
+  on:copy={() => {
+    console.log("copied");
+  }}
+/>
+
+<CopyButton
+  iconDescription="Custom feedback"
+  text="text"
+  feedback="Copied to clipboard"
+  feedbackTimeout={0}
+/>
+
+<CopyButton
+  text="Custom copy function"
+  iconDescription="Custom copy function"
+  copy={(text) => {
+    console.log(`Custom copy: ${text}`);
+  }}
+/>

tests/CopyButton/CopyButton.test.ts

@@ -0,0 +1,69 @@
+import { render, screen } from "@testing-library/svelte";
+import { user } from "../setup-tests";
+import CopyButton from "./CopyButton.test.svelte";
+
+describe("CopyButton", () => {
+  const getCopyButton = (label: string) =>
+    screen.getByRole("button", { name: label });
+
+  beforeEach(() => {
+    Object.defineProperty(navigator, "clipboard", {
+      value: { writeText: () => Promise.resolve() },
+      writable: true,
+    });
+  });
+
+  it("renders and functions correctly", async () => {
+    const consoleLog = vi.spyOn(console, "log");
+    render(CopyButton);
+
+    const button = getCopyButton("Basic");
+    expect(button).toHaveAttribute("aria-live", "polite");
+
+    await user.click(button);
+    expect(consoleLog).toHaveBeenCalledWith("copied");
+
+    const feedback = button.querySelector(".bx--copy-btn__feedback");
+    expect(feedback).toHaveTextContent("Copied!");
+  });
+
+  it("supports custom feedback text and timeout", async () => {
+    render(CopyButton);
+
+    const button = getCopyButton("Custom feedback");
+    await user.click(button);
+
+    const feedback = button.querySelector(".bx--copy-btn__feedback");
+    expect(feedback).toHaveTextContent("Copied to clipboard");
+
+    await new Promise((resolve) => setTimeout(resolve, 0));
+    expect(button).toHaveClass("bx--copy-btn--fade-out");
+  });
+
+  it("supports custom copy function", async () => {
+    const consoleLog = vi.spyOn(console, "log");
+    const clipboard = vi.spyOn(navigator.clipboard, "writeText");
+    render(CopyButton);
+
+    const button = getCopyButton("Custom copy function");
+    await user.click(button);
+    expect(consoleLog).toHaveBeenCalledWith(
+      "Custom copy: Custom copy function",
+    );
+    expect(clipboard).not.toHaveBeenCalled();
+  });
+
+  it("handles clipboard API errors", async () => {
+    const consoleLog = vi.spyOn(console, "log");
+    Object.defineProperty(navigator, "clipboard", {
+      value: { writeText: () => Promise.reject("Clipboard error") },
+      writable: true,
+    });
+
+    render(CopyButton);
+
+    const button = getCopyButton("Basic");
+    await user.click(button);
+    expect(consoleLog).toHaveBeenCalledWith("Clipboard error");
+  });
+});