swc-project/swc · error · swc_css_parser::Error

Expected ident or string

Error message

Expected ident or string

What it means

Fired while parsing the name of a @keyframes at-rule: the current token was neither an ident nor a string, so no valid keyframes name (a <custom-ident> or a <string>) could be produced. Input at fault is @keyframes with a missing or malformed name, e.g. `@keyframes { ... }` or `@keyframes 2x { ... }`.

Source

Thrown at crates/swc_css_parser/src/parser/at_rules/mod.rs:906

                }
            }
            tok!("ident") => {
                let custom_ident: CustomIdent = self.parse()?;

                if matches_eq_ignore_ascii_case!(custom_ident.value, "none") {
                    return Err(Error::new(
                        custom_ident.span,
                        ErrorKind::InvalidCustomIdent(custom_ident.value),
                    ));
                }

                Ok(KeyframesName::CustomIdent(Box::new(custom_ident)))
            }
            tok!("string") => Ok(KeyframesName::Str(Box::new(self.parse()?))),
            _ => {
                let span = self.input.cur_span();

                Err(Error::new(span, ErrorKind::Expected("ident or string")))
            }
        }
    }
}

impl<I> Parse<KeyframeSelector> for Parser<I>
where
    I: ParserInput,
{
    fn parse(&mut self) -> PResult<KeyframeSelector> {
        match cur!(self) {
            tok!("ident") => {
                let ident: Ident = self.parse()?;
                let lower = ident.value.to_ascii_lowercase();

                if lower != "from" && lower != "to" {
                    return Err(Error::new(
                        ident.span,

View on GitHub (pinned to 5176682b65)

Solutions

1. Give @keyframes a valid ident or string name
2. Report the error from the parse result
3. Fix the CSS source

When it happens

Trigger: Thrown at crates/swc_css_parser/src/parser/at_rules/mod.rs:906 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/3813a961b8711a20. Report an issue: GitHub.