Unable to compose class named `default`

[mrginglymus]

input:

.default {
  color: blue;
}

.foo {
  composes: default;
  color: red;
}

expected output:

{
  "default": {
    "name": "EgL3uq_default",
    "composes": [],
    "isReferenced": false
  },
  "foo": {
    "name": "EgL3uq_foo",
    "composes": [
      {
        "type": "local",
        "name": "EgL3uq_default"
      }
    ],
    "isReferenced": false
  }
}

actual output:

{
  "default": {
    "name": "EgL3uq_default",
    "composes": [],
    "isReferenced": false
  },
  "foo": {
    "name": "EgL3uq_foo",
    "composes": [],
    "isReferenced": false
  }
}

Playground Reproduction

[mrginglymus]

Ah, it appears the problem is that

lightningcss/src/values/ident.rs

Lines 34 to 37 in fc7f350

	let valid = match_ignore_ascii_case! { &ident,
	"initial" | "inherit" | "unset" | "default" | "revert" | "revert-layer" => false,
	_ => true
	};

disallows idents with these reserved names. However, I'm not sure that that is required by the css modules spec; it's certainly not explicitly mentioned, and the class references aren't really custom idents.