Pass `@warn` as warnings to webpack

[adiron]

At the moment I'm working on a project with a workflow that uses sass-loader in order to compile SCSS.

There is a Sass mixin with a @warn directive in it. At the moment it outputs warnings such as this to stdout:

WARNING: Warning message
         on line 56 of src/test.scss, in function `something`

I think it could be more useful if Webpack was aware of the warning. In the same way that eslint-loader can raise warnings. e.g.:

/path/to/code/file.js
  1:20  warning  'foobar' is defined but never used  no-unused-vars

Is this something I can do right now with sass-loader in any way? I think developers using similar workflows could benefit from seeing the warnings in a more organized fashion coming out of Webpack, rather than scattered warnings straight into stdout

[alexander-akait]

@adiron PR welcome 👍

[adiron]

I'll see what I can do, but I doubt I have the expertise atm. Any pointers for what I should look into?

[alexander-akait]

@adiron We should use webpack api for this https://webpack.js.org/api/loaders/#this-emitwarning

[alexander-akait]

@nex3 Hi, it is possible to implement the logger (logger.warn, logger.error, logger.debug and etc) option for sass? Will be great to use own logging system for better DX

[alexander-akait]

@nex3 Hello, can we put @warn and @error in result after run render?

[nex3]

@alexander-akait Plugins will be able to access @warn using the proposed logger API. I'm not sure how it would make sense to put @error in the render result, though, since @error causes compilation to fail entirely and throw an error rather than returning a result object.

[alexander-akait]

@nex3 Great, so we will implement this after the proposed logger API shipped