When creating SharePoint framework webparts in Visual Studio code, out of the box integration with SASS files (.scss) does not work. You get errors which look like this (when you’re using ts-lint that is).

This also causes pain and angst when it comes to running CI / CD in Azure DevOps and the build breaks because npm test wont run – the enzyme rendering of the component wont work because it cannot find the scss file.

Natively, typescript does not understand scss as an import and you need to let it know that it’s ok to include.

You solve this problem in two steps:

1. Create a declarations.d.ts file in the root of the project
2. Add a reference into the tsconfig file to use the declarations file

declarations.d.ts

// We need to tell TypeScript that when we write "import styles from './styles.scss' we mean to load a module (to look for a './styles.scss.d.ts').
   declare module "*.scss" {
   const content: { [className: string]: string };
   export = content;
}

tsconfig.json

//add the following
"include": [
    "src/**/*.ts", 
    "declarations.d.ts"
  ],

and that’s all 🙂