Upgrade integration tests to use Vitest (#6021)

integration-tests/globalSetup.ts

@@ -0,0 +1,55 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { mkdir, readdir, rm } from 'fs/promises';
+import { join, dirname } from 'path';
+import { fileURLToPath } from 'url';
+
+const __dirname = dirname(fileURLToPath(import.meta.url));
+const rootDir = join(__dirname, '..');
+const integrationTestsDir = join(rootDir, '.integration-tests');
+let runDir = ''; // Make runDir accessible in teardown
+
+export async function setup() {
+  runDir = join(integrationTestsDir, `${Date.now()}`);
+  await mkdir(runDir, { recursive: true });
+
+  // Clean up old test runs, but keep the latest few for debugging
+  try {
+    const testRuns = await readdir(integrationTestsDir);
+    if (testRuns.length > 5) {
+      const oldRuns = testRuns.sort().slice(0, testRuns.length - 5);
+      await Promise.all(
+        oldRuns.map((oldRun) =>
+          rm(join(integrationTestsDir, oldRun), {
+            recursive: true,
+            force: true,
+          }),
+        ),
+      );
+    }
+  } catch (e) {
+    console.error('Error cleaning up old test runs:', e);
+  }
+
+  process.env.INTEGRATION_TEST_FILE_DIR = runDir;
+  process.env.GEMINI_CLI_INTEGRATION_TEST = 'true';
+  process.env.TELEMETRY_LOG_FILE = join(runDir, 'telemetry.log');
+
+  if (process.env.KEEP_OUTPUT) {
+    console.log(`Keeping output for test run in: ${runDir}`);
+  }
+  process.env.VERBOSE = process.env.VERBOSE ?? 'false';
+
+  console.log(`\nIntegration test output directory: ${runDir}`);
+}
+
+export async function teardown() {
+  // Cleanup the test run directory unless KEEP_OUTPUT is set
+  if (process.env.KEEP_OUTPUT !== 'true' && runDir) {
+    await rm(runDir, { recursive: true, force: true });
+  }
+}