`@at-root` should now work properly in a nested import as long as the
only `@use` or `@forward` rules present are for built-in modules.
This is a partial but not complete fix for #1347. It's a bit hacky to
special case built-in modules here, but since they represent the only
real legitimate case for using this combination of features, it lets us
fix the bug for this case and avoid the bordering-on-infeasible work of
fixing this for user-defined modules.
These getters are only available through the sass_api package. This
will allow the Sass embedded compiler to more explicitly send the
color information it has on hand.
Fixes#1401 and #1414.
Adds `Dependency`, `SassDeclaration`, and `SassReference` interfaces,
which expose some getters that multiple AST nodes have in common with a
single type.
These also add getters for common subspans (URL, name, and namespace) to
the interfaces.
