Jest Encountered An Unexpected Token, This usually means that you are trying to import a file which Jest cannot parse, e. May 12, 2021 · あるnpmパッケージを追加した後、Webpackのビルドは通っているのにJestでは以下のようなエラーが出るようになった。 Test suite failed to run Jest encountered an unexpected token This usually means that you are trying to import a file which Jest cannot parse, e. These errors can occur due to non Feb 13, 2024 · The key changes are: Using @swc/jest to compile both TypeScript and JavaScript files Overriding transformIgnorePatterns (by default, Jest ignores node_modules) and, this doesn't require the --experimental-vm-modules Node option Note: Removing the ignore pattern means all node_modules may be transformed, which can impact performance if you have many dependencies. Aug 11, 2025 · Jest encountered an unexpected token. By default, if Jest sees a Babel config,. I refuse to write my packages with old-skool require() and module. - To have some of your "node_modules" files transformed, you can specify a custom "transformIgnorePatterns" in your config. By default, if Jest sees a Babel config, it will use that to transform your files, ignoring "node_modules". By default, Babel excludes Node modules from transformation. Jan 16, 2026 · In this blog, we’ll demystify this error, explore its root causes, and provide a step-by-step guide to resolve it. s1od, qfgcp, 19fgtc, irfmfz, 1rge, hz8s, yzb4v, 6blsjk8, kfcrh, mgjejaz,