expo / expo/dev-plugins

Jest encountered an unexpected token

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Dominant language
TypeScript
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Description

When adding **any** of the dev-plugins, Jest is throwing the following error:

```
Jest encountered an unexpected token

Jest failed to parse a file. This happens e.g. when your code or its dependencies use non-standard JavaScript syntax, or when Jest is not configured to support such syntax.

Out of the box Jest supports Babel, which will be used to transform your files into valid JS based on your Babel configuration.

By default "node_modules" folder is ignored by transformers.

Here's what you can do:
• If you are trying to use ECMAScript Modules, see https://jestjs.io/docs/ecmascript-modules for how to enable it.
• If you are trying to use TypeScript, see https://jestjs.io/docs/getting-started#using-typescript
• To have some of your "node_modules" files transformed, you can specify a custom "transformIgnorePatterns" in your config.
• If you need a custom transformation specify a "transform" option in your config.
• If you simply want to mock your non-JS modules (e.g. binary assets) you can stub them out with the "moduleNameMapper" config option.

You'll find more details and examples of these config options in the docs:
https://jestjs.io/docs/configuration
For information about custom transformations, see:
https://jestjs.io/docs/code-transformation

Details:

C:\Projects\xxx\node_modules\@dev-plugins\async-storage\build\index.js:1
({"Object.":function(module,exports,require,__dirname,__filename,jest){export let useAsyncStorageDevTools;
^^^^^^

SyntaxError: Unexpected token 'export'

3 |
4 |
> 5 | import { useAsyncStorageDevTools } from "@dev-plugins/async-storage";
| ^
6 | import { useNavigationContainerRef } from "expo-router";
7 | import React, { PropsWithChildren } from "react";
8 |

at Runtime.createScriptFromCode (node_modules/jest-runtime/build/index.js:1505:14)
at Object.require (src/app/DevToolsPluginsContainer.tsx:5:1)
at Object.require (src/app/_layout.tsx:11:1)
at Object.require (__tests__/app/_layout.test.tsx:7:1)
```

---

```
expo-env-info 1.2.2 environment info:
System:
OS: Windows 11 10.0.26100
Binaries:
Node: 22.12.0 - ~\AppData\Local\nvs\node\22.12.0\x64\node.EXE
Yarn: 1.22.22 - ~\AppData\Local\nvs\node\22.12.0\x64\yarn.CMD
npm: 11.0.0 - ~\AppData\Local\nvs\node\22.12.0\x64\npm.CMD
IDEs:
Android Studio: AI-242.23339.11.2421.12700392
npmPackages:
expo: ^52.0.25 => 52.0.25
expo-router: ~4.0.16 => 4.0.16
react: 18.3.1 => 18.3.1
react-dom: 18.3.1 => 18.3.1
react-native: 0.76.6 => 0.76.6
react-native-web: ^0.19.13 => 0.19.13
Expo Workflow: bare
```

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