test: add tabs tests

tests/tabs.spec.ts

@@ -0,0 +1,53 @@
+import { ElectronApplication, expect, test } from "@playwright/test";
+import { describe } from "node:test";
+import { launchElectronApp } from "./utils/app.js";
+
+let electronApp: ElectronApplication;
+
+test.beforeEach(async () => {
+	electronApp = await launchElectronApp();
+});
+
+test.afterEach(async () => {
+	await electronApp.close();
+});
+
+describe("tabs", () => {
+	test("should show no tabs screen", async () => {
+		const window = await electronApp.firstWindow();
+
+		const screen = window.locator(".no-tabs-exist");
+		const tabs = window.locator("tab-group .tabs > .tab");
+
+		await expect(screen).toBeHidden();
+		await expect(tabs).toHaveCount(1);
+
+		const tab = tabs.first();
+		await tab.getByRole("button", { name: "×" }).click();
+
+		await expect(tabs).toHaveCount(0);
+		await expect(screen).toBeVisible();
+		await expect(screen).toContainText("No tabs are opened");
+		await expect(screen).toContainText(
+			"Add a new tab to start making awesome things.",
+		);
+	});
+
+	test("should add a tab from no tabs screen", async () => {
+		const window = await electronApp.firstWindow();
+
+		const tabs = window.locator("tab-group .tabs > .tab");
+		const tab = tabs.first();
+		await tab.getByRole("button", { name: "×" }).click();
+
+		await expect(tabs).toHaveCount(0);
+
+		const addTabButton = window.getByRole("button", {
+			name: "Create a tab",
+		});
+		await addTabButton.waitFor({ state: "visible" });
+		await addTabButton.click();
+
+		await expect(tabs).toHaveCount(1);
+	});
+});