zed-industries/zed · error

incompatible grammar

Error message

incompatible grammar

What it means

Panics when parser.set_language fails while binding a tree-sitter grammar's language to the pooled parser in parse_text. The 'incompatible grammar' error fires when the grammar's ABI version is incompatible with the linked tree-sitter runtime, or the language node is corrupt — typically after upgrading tree-sitter without rebuilding vendored WASM/native grammars.

Source

Thrown at crates/language/src/language.rs:1450

}

impl PartialEq for Language {
    fn eq(&self, other: &Self) -> bool {
        self.id.eq(&other.id)
    }
}

impl Eq for Language {}

impl Debug for Language {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        f.debug_struct("Language")
            .field("name", &self.config.name)
            .finish()
    }
}

pub(crate) fn parse_text(grammar: &Grammar, text: &Rope, old_tree: Option<Tree>) -> Tree {
    with_parser(|parser| {
        parser
            .set_language(&grammar.ts_language)
            .expect("incompatible grammar");
        let mut chunks = text.chunks_in_range(0..text.len());
        parser
            .parse_with_options(
                &mut move |offset, _| {
                    chunks.seek(offset);
                    chunks.next().unwrap_or("").as_bytes()
                },
                old_tree.as_ref(),
                None,
            )
            .unwrap()
    })
}

View on GitHub (pinned to 9d272b0363)

Solutions

1. Rebuild/re-vendor the grammars so their tree-sitter ABI matches the runtime version
2. Check the LANGUAGE_VERSION/LANGUAGE_VERSION_MINIMUM reported by tree-sitter and pin compatible crate versions
3. Propagate the error from parse_text (return Result) so the language can be disabled instead of crashing parsing

When it happens

Trigger: Thrown at crates/language/src/language.rs:1382 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of zed-industries/zed@9d272b0363 (2026-08-20). Data as JSON: /api/errors/49e74cf64279e53e. Report an issue: GitHub.