Parse CSS modules syntax for @keyframes :local(ident)

[jsnajdr]

The VSCode CSS parser fails to parse the CSS modules syntax for scoping keyframes identifiers:

The SASS tool (both the Dart and C++) implementations parse the @keyframes identifier either as a selector, or just as a generic raw params string (anything between atrule and start of the block), I'm not sure. But they are able to pass the :local(ident) string to a tool like postcss-modules which transforms it into a valid, locally scoped identifier.

[mirka]

Might be obvious given the error ("identifier expected" rather than "unknown pseudo class" or something), but I'll add that this also isn't resolved by adding the pseudos to css.customData, e.g.:

{
    "version": 1.1,
    "pseudoClasses": [
        {
            "name": ":local",
            "description": "css modules local"
        }
    ]
}

[jsnajdr]

Pseudoclasses are used only when scoping selectors. This is CSS modules syntax that is already syntactically valid:

:local {
  .foo {
    color: blue;
  }
}

But @keyframes :local(foo) is a special incompatible extension. According to the standard, it should be only a simple string identifier. And the VSCode CSS parser really insists that it's an identifier.