Remove PostCSS warning

[StefanRein]

This removes following warning:

Remove warning: Without from option PostCSS could generate wrong source map or do not find Browserslist config. Set it to CSS file path or to undefined to prevent this warning

from: the input file name (most runners set it automatically).
Source: https://github.com/postcss/postcss

Fixes #1359 #13763
#1359
ionic-team/ionic-framework#13763

Short description of what this resolves:

This removes the PostCSS warning, which is resulting in an error in our automated builds.

Changes proposed in this pull request:

• Just add from field with an undefined value, as mentioned in the warning.

Fixes: #1359 #13763

[krishnakumarik]

In which file i have to add the from field.actually i have a from field in ionic-app-scripts-package.json. and from filed is having the value like this "@ionic/app-scripts@latest".now what i have to do.plz help me out.
and in my project postcss version is "6.0.13",

[krishnakumarik]

ok founded in sass.js .it is working.

[con17man]

thanks @krishnakumarik

you can find sass.js file under /node_modules/@ionic/app-scripts/dist/sass.js.
inside search for var postcssOptions and add from: undefined,.

it should look like this:

var postcssOptions = {
    from: undefined,
    to: path_1.basename(sassConfig.outFile),
    map: autoPrefixerMapOptions
};

[StefanRein]

@krishnakumarik @con17man You should not modify any files in the node_modules directory. If you update packages, reinstall them, installing them in a new project, any modifications are gone.

I did write here some suggestions how to solve this temporarily, so you don't have to modify files in the node_modules folder: ionic-team/ionic-framework#13763

[OooOooosss]

Modifying the sass.ts file can solve the problem, but it's not a good way to do it

[bleuscyther]

+1

[imhoffd]

Thank you @StefanRein much appreciated 😄