swc-project/swc · error · Error

The CSS-wide keywords are not valid custom ident, found '{va

Error message

The CSS-wide keywords are not valid custom ident, found '{value}'

What it means

Fired by the CustomIdent parser: the ident matched a CSS-wide keyword ('initial', 'inherit', 'unset', 'revert', 'default', case-insensitive). Per spec these keywords are excluded from <custom-ident>, so using one as a custom ident is invalid.

Source

Thrown at crates/swc_css_parser/src/parser/values_and_units/mod.rs:1837

}

impl<I> Parse<CustomIdent> for Parser<I>
where
    I: ParserInput,
{
    fn parse(&mut self) -> PResult<CustomIdent> {
        let span = self.input.cur_span();

        if !is!(self, Ident) {
            return Err(Error::new(span, ErrorKind::Expected("Ident")));
        }

        match bump!(self) {
            Token::Ident { value, raw, .. } => {
                if matches_eq_ignore_ascii_case!(
                    value, "initial", "inherit", "unset", "revert", "default"
                ) {
                    return Err(Error::new(span, ErrorKind::InvalidCustomIdent(value)));
                }

                Ok(CustomIdent {
                    span,
                    value,
                    raw: Some(raw),
                })
            }
            _ => {
                unreachable!()
            }
        }
    }
}

impl<I> Parse<DashedIdent> for Parser<I>
where
    I: ParserInput,

View on GitHub (pinned to 5176682b65)

Solutions

1. Choose a name that is not a CSS-wide keyword
2. Escape or rename the identifier if it must keep a similar meaning

When it happens

Trigger: Thrown at crates/swc_css_parser/src/parser/values_and_units/mod.rs:1837 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of swc-project/swc@5176682b65 (2026-08-17). Data as JSON: /api/errors/662ab1591fe37eed. Report an issue: GitHub.