function-name-case can easily break Sass custom functions if left at its default value (inherited from stylelint-config-standard) #231
Description
The rule function-name-case is set to 'lower' in stylelint-config-standard. That makes a lot of sense in pure CSS, where functions are usually all lowercase.
But in Sass, you can create your own functions, and you can name them in camelCase if you want. This rule, being auto-fixable, is pretty dangerous when it comes to accidentally breaking user code.
The simplest fix I can imagine is to disable the rule ([ null ]) in this shareable config, so that people's Sass functions can't be broken, but there may be a smarter way to detect pure CSS functions and only activate the rule for those.