swc-project/swc · error

Expected url or function (with 'url' or 'src' name) token

Error message

Expected url or function (with 'url' or 'src' name) token

What it means

Fired while parsing a Url: the current token was neither a url(...) token nor a Function token, so no URL value could be produced. This `if !is_one_of!(self, Url, Function)` check is a validation guard; input at fault is a url-required context (e.g. @import, background-image) receiving a bare ident or string instead of `url(...)`.

Source

Thrown at crates/swc_css_parser/src/parser/values_and_units/mod.rs:2594

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

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

        if !is_one_of!(self, Url, Function) {
            return Err(Error::new(
                span,
                ErrorKind::Expected("url or function (with 'url' or 'src' name) token"),
            ));
        }

        match bump!(self) {
            Token::Url { value, raw } => {
                let name_length = raw.0.len() as u32;
                let name = Ident {
                    span: Span::new(span.lo, span.lo + BytePos(name_length)),
                    value: self.input.atom("url"),
                    raw: Some(raw.0),
                };
                let value = Some(Box::new(UrlValue::Raw(UrlValueRaw {
                    span: Span::new(span.lo + BytePos(name_length + 1), span.hi - BytePos(1)),
                    value,
                    raw: Some(raw.1),
                })));

View on GitHub (pinned to 5176682b65)

Solutions

1. Use url(...) or src(...) syntax with a valid URL argument
2. Quote the URL if it contains special characters

When it happens

Trigger: Thrown at crates/swc_css_parser/src/parser/values_and_units/mod.rs:2594 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/6869dad1bf6e322a. Report an issue: GitHub.