Add a lint for an explicit namespace that's the same as the default

[nex3]

If a user writes something like @use "foo" as foo, the as foo is totally redundant since it's the same as the default namespace that the @use rule would provide on its own. It would be nice to have a lint for this case.

[airyboy]

Any ideas for the name of this rule?
at-use-no-redundant-alias?

[thibaudcolas]

Based on the Sass @use documentation and the Sass Module System spec, I think a good name would be at-use-no-redundant-namespace. I quite like "alias" too, but the as-clause is not described with that term anywhere in the official documentation.

---

It took me a few months of occasional @use usage to discover that there was in fact a default namespace, extracted from the last component of the import URL. I’d almost be tempted to ask for the opposite rule (or a true/false at-use-redundant-namespace) to mandate the redundancy –  I find this automatic default very un-intuitive since the import path otherwise looks like any other string.

It might just be a matter of getting used to / seeing it used more / having better syntax highlighting that highlights the last component of the path as an identifier – but for now, I’d rather do:

@use "src/corners" as corners;
@use "sass:math" as math;