docs: explain how to reset storage state (#26422)

References #26374.

docs/src/auth.md

@@ -654,3 +654,19 @@ await context.AddInitScriptAsync(@"(storage => {
     }
   })('" + loadedSessionStorage + "')");
 ```
+
+### Avoid authentication in some tests
+* langs: js
+
+You can reset storage state in a test file to avoid authentication that was set up for the whole project.
+
+```js title="not-signed-in.spec.ts"
+import { test } from '@playwright/test';
+
+// Reset storage state for this file to avoid being authenticated
+test.use({ storageState: { cookies: [], origins: [] } });
+
+test('not signed in test', async ({ page }) => {
+  // ...
+});
+```

docs/src/test-api/class-testoptions.md

@@ -492,6 +492,21 @@ export default defineConfig({
 });
 ```
 
+**Details**
+
+When storage state is set up in the config, it is possible to reset storage state for a file:
+
+```js title="not-signed-in.spec.ts"
+import { test } from '@playwright/test';
+
+// Reset storage state for this file to avoid being authenticated
+test.use({ storageState: { cookies: [], origins: [] } });
+
+test('not signed in test', async ({ page }) => {
+  // ...
+});
+```
+
 ## property: TestOptions.testIdAttribute
 * since: v1.27
 

packages/playwright-test/types/test.d.ts

@@ -4012,6 +4012,22 @@ export interface PlaywrightTestOptions {
    * });
    * ```
    *
+   * **Details**
+   *
+   * When storage state is set up in the config, it is possible to reset storage state for a file:
+   *
+   * ```js
+   * // not-signed-in.spec.ts
+   * import { test } from '@playwright/test';
+   *
+   * // Reset storage state for this file to avoid being authenticated
+   * test.use({ storageState: { cookies: [], origins: [] } });
+   *
+   * test('not signed in test', async ({ page }) => {
+   *   // ...
+   * });
+   * ```
+   *
    */
   storageState: StorageState | undefined;
   /**