test: Add Playwright browser config to Vitest; Add GitHub test workflow.

package.json

@@ -17,7 +17,8 @@
     "lint:check:js": "tsc --noEmit && eslint . --max-warnings 0",
     "lint:fix:js": "npm run lint:check:js -- --fix",
     "release": "git diff --exit-code && task package && npm publish",
-    "test": "vitest run"
+    "test:init": "PLAYWRIGHT_BROWSERS_PATH=0 npm exec playwright -- install --with-deps",
+    "test": "PLAYWRIGHT_BROWSERS_PATH=0 vitest run"
   },
   "type": "module",
   "files": [
@@ -39,6 +40,7 @@
   },
   "devDependencies": {
     "@types/node": "^22.19.9",
+    "@vitest/browser-playwright": "^4.0.18",
     "eslint": "^9.39.2",
     "eslint-config-yscope": "^1.1.2",
     "typescript": "^5.9.3",

taskfiles/test.yaml

@@ -4,6 +4,10 @@ tasks:
   default:
     deps: ["js"]
 
-  js:
+  init:
     deps: [":package", ":node-modules"]
+    cmd: "npm run test:init"
+
+  js:
+    deps: ["init"]
     cmd: "npm run test {{.CLI_ARGS}}"

vitest.config.ts

@@ -1,10 +1,36 @@
 import {defineConfig} from "vitest/config";
+import {playwright} from "@vitest/browser-playwright";
 
 
 export default defineConfig({
     test: {
-        include: ["test/**/*.test.ts"],
-        environment: "node",
-        testTimeout: 30_000,
+        globalSetup: "test/globalSetup.ts",
+        projects: [
+            {
+                test: {
+                    name: "node",
+                    include: ["test/**/*.test.ts"],
+                    environment: "node",
+                    testTimeout: 30_000,
+                },
+            },
+            {
+                test: {
+                    name: "browser",
+                    include: ["test/**/*.test.ts"],
+                    testTimeout: 30_000,
+                    browser: {
+                        enabled: true,
+                        provider: playwright(),
+                        instances: [
+                            {browser: "chromium"},
+                            {browser: "firefox"},
+                            {browser: "webkit"},
+                        ],
+                        headless: true,
+                    },
+                },
+            },
+        ],
     },
 });