test(windows): run the integration suite on Windows

.github/workflows/ci.yml

@@ -10,10 +10,11 @@ concurrency:
 
 jobs:
   test:
-    runs-on: ubuntu-latest
+    runs-on: ${{ matrix.os }}
     strategy:
       fail-fast: false
       matrix:
+        os: [ubuntu-latest, windows-latest]
         node-version: [20, 22]
 
     steps:
@@ -53,14 +54,14 @@ jobs:
         run: npm run test:coverage
 
       - name: Upload coverage reports to Codecov
-        if: matrix.node-version == 20
+        if: matrix.os == 'ubuntu-latest' && matrix.node-version == 20
         uses: codecov/codecov-action@v5
         with:
           token: ${{ secrets.CODECOV_TOKEN }}
           fail_ci_if_error: false
 
       - name: Upload artifacts
-        if: matrix.node-version == 20
+        if: matrix.os == 'ubuntu-latest' && matrix.node-version == 20
         uses: actions/upload-artifact@v7
         with:
           name: dist

docs/ci-and-release.md

@@ -37,13 +37,6 @@ Release flow
 3) The `version-check` job validates the tag vs. package.json.
 4) `release` creates a GitHub Release; `publish` publishes to npm.
 
-Windows Integration Tests
-- On Windows, vitest has known issues with process forking when running integration tests that spawn Firefox.
-- See: https://github.com/mozilla/firefox-devtools-mcp/issues/33
-- To work around this, we use a separate test runner (`scripts/run-integration-tests-windows.mjs`) that runs integration tests directly via Node.js without vitest's process isolation.
-- The CI workflow detects Windows and automatically uses this runner instead of vitest for integration tests.
-- Unit tests still run via vitest on all platforms.
-
 Notes
 - If you want Codecov upload to run, switch CI test step to `npm run test:coverage` or generate `coverage/lcov.info`.
 - Provenance is enabled for npm publish (Node 20+).

package.json

@@ -46,8 +46,7 @@
     "test:mozlog": "node scripts/test-mozlog.js",
     "test:navigation": "node scripts/test-navigation.js",
     "test:privileged": "node scripts/test-privileged-context.js",
-    "test:screenshot": "node scripts/test-screenshot.js",
-    "test:integration:win": "node scripts/run-integration-tests-windows.mjs"
+    "test:screenshot": "node scripts/test-screenshot.js"
   },
   "keywords": [
     "mcp",

tests/helpers/firefox.ts

@@ -6,6 +6,9 @@
 import { FirefoxClient } from '@/firefox/index.js';
 import type { FirefoxLaunchOptions } from '@/firefox/types.js';
 import type { SnapshotNode } from '@/firefox/snapshot/types.js';
+// Aliased: several helpers below name a promise callback parameter `resolve`.
+import { resolve as resolvePath } from 'node:path';
+import { fileURLToPath, pathToFileURL } from 'node:url';
 
 /**
  * Creates a headless Firefox client for testing
@@ -144,3 +147,19 @@ export async function waitForElementInSnapshot(
 export async function waitForPageLoad(delayMs = 300): Promise<void> {
   await new Promise((resolve) => setTimeout(resolve, delayMs));
 }
+
+/**
+ * Absolute path to the shared fixtures directory.
+ */
+export const fixturesPath = resolvePath(
+  fileURLToPath(new URL('.', import.meta.url)),
+  '../fixtures'
+);
+
+/**
+ * Builds a file:// URL for a fixture. Interpolating `file://${path}` breaks on
+ * Windows (the drive letter parses as the host); pathToFileURL does not.
+ */
+export function fixtureUrl(fileName: string): string {
+  return pathToFileURL(resolvePath(fixturesPath, fileName)).href;
+}

tests/helpers/fs.ts

@@ -0,0 +1,9 @@
+import { rmSync } from 'node:fs';
+
+/**
+ * Recursive delete that tolerates Windows still holding the handles: `force`
+ * suppresses ENOENT but not the ENOTEMPTY/EPERM a just-closed file causes.
+ */
+export function removeDir(dir: string): void {
+  rmSync(dir, { recursive: true, force: true, maxRetries: 5, retryDelay: 50 });
+}