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.

The error "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." occurs because Jest is unable to handle some modern or non-standard JavaScript/TypeScript syntax by default. This can happen if:

• The code includes JSX/TSX (React syntax) or ECMAScript Modules (ESM) that Jest is not configured to transform.
• Some dependencies in "node_modules" use modern JavaScript that Jest does not transform by default.
• Jest lacks proper Babel or TypeScript transformer configuration to convert the code into a format Jest can execute.

To fix the issue, common steps include:

1. Ensure you have the correct Jest transformer configured, such as babel-jest for Babel or ts-jest for TypeScript.
2. Configure Jest to transform files with JSX/TSX by setting up the proper transform option.
3. For ESM packages inside node_modules that cause issues, whitelist these packages by adjusting the transformIgnorePatterns option in the Jest config to explicitly transform them.
4. Check your Babel or TypeScript config (babel.config.js, tsconfig.json) to ensure JSX mode and module settings are compatible with Jest.
5. In some cases, provide a moduleNameMapper or custom resolver in Jest config to handle problematic dependencies.

This error is common when working with React, TypeScript, or modern JavaScript SDKs, and careful configuration of Jest and Babel/TypeScript is key to resolving it.