error TS6504: is a JavaScript file. Did you mean to enable the 'allowJs' option?

9 min read

The error message "error TS6504: is a JavaScript file. Did you mean to enable the 'allowJs' option?" is a TypeScript compiler error message.

This error occurs when you try to compile a JavaScript file using the TypeScript compiler. By default, the TypeScript compiler only allows TypeScript files to be compiled. If you need to compile JavaScript files, you need to enable the 'allowJs' compiler option.

To resolve this issue, you can do the following:

  1. Make sure you have TypeScript installed globally on your system:

    npm install -g typescript

  2. Create a tsconfig.json file in the root of your project if you don't have one already.

  3. Open the tsconfig.json file and add the following compiler option:

    {
  "compilerOptions": {
    "allowJs": true
  }
}

  4. Save the tsconfig.json file.

  5. Try compiling the JavaScript file again using the TypeScript compiler.

This will enable the 'allowJs' option and allow you to compile both TypeScript and JavaScript files.