From 3d48ebcb992c2ceaf1a50be40ff1625203ccdba8 Mon Sep 17 00:00:00 2001
From: Vladimir <sleuths.slews0s@icloud.com>
Date: Wed, 28 Jan 2026 13:14:27 +0100
Subject: [PATCH] fix: show a warning when `browser.isolate` is used (#9410)

---
 packages/vitest/src/node/config/resolveConfig.ts | 5 +++++
 test/coverage-test/test/isolation.test.ts        | 4 ----
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/packages/vitest/src/node/config/resolveConfig.ts b/packages/vitest/src/node/config/resolveConfig.ts
index cb98436cf..a7f4fc33b 100644
--- a/packages/vitest/src/node/config/resolveConfig.ts
+++ b/packages/vitest/src/node/config/resolveConfig.ts
@@ -736,6 +736,11 @@ export function resolveConfig(
 
   resolved.browser.enabled ??= false
   resolved.browser.headless ??= isCI
+  if (resolved.browser.isolate) {
+    logger.console.warn(
+      c.yellow('`browser.isolate` is deprecated. Use top-level `isolate` instead.'),
+    )
+  }
   resolved.browser.isolate ??= resolved.isolate ?? true
   resolved.browser.fileParallelism
     ??= options.fileParallelism ?? mode !== 'benchmark'
diff --git a/test/coverage-test/test/isolation.test.ts b/test/coverage-test/test/isolation.test.ts
index 90b885616..e1dd8cd5c 100644
--- a/test/coverage-test/test/isolation.test.ts
+++ b/test/coverage-test/test/isolation.test.ts
@@ -27,10 +27,6 @@ for (const isolate of [true, false]) {
         coverage: {
           reporter: 'json',
         },
-
-        browser: {
-          isolate,
-        },
       })
 
       const coverageMap = await readCoverageMap()
-- 
2.51.2