zed-industries/zed · error

missing python/semantic_token_rules.json

Error message

missing python/semantic_token_rules.json

What it means

Panics because grammars::get_file("python/semantic_token_rules.json") returned None: the Python semantic-token rules asset is missing from the compiled-in grammars files. As with the other languages, this is a packaging invariant — the vendored file was not embedded, not a runtime condition.

Source

Thrown at crates/languages/src/python.rs:57

use util::paths::PathStyle;
use util::rel_path::RelPath;

use http_client::github_download::{GithubBinaryMetadata, download_server_binary};
use parking_lot::Mutex;
use std::str::FromStr;
use std::{
    borrow::Cow,
    fmt::Write,
    future::Future,
    path::{Path, PathBuf},
    sync::Arc,
};
use task::{ShellKind, TaskTemplate, TaskTemplates, VariableName};
use util::{ResultExt, maybe};

pub(crate) fn semantic_token_rules() -> SemanticTokenRules {
    let content = grammars::get_file("python/semantic_token_rules.json")
        .expect("missing python/semantic_token_rules.json");
    let json = std::str::from_utf8(&content.data).expect("invalid utf-8 in semantic_token_rules");
    settings::parse_json_with_comments::<SemanticTokenRules>(json)
        .expect("failed to parse python semantic_token_rules.json")
}

#[derive(Debug, Serialize, Deserialize)]
pub(crate) struct PythonToolchainData {
    #[serde(flatten)]
    environment: PythonEnvironment,
    #[serde(skip_serializing_if = "Option::is_none")]
    activation_scripts: Option<HashMap<ShellKind, PathBuf>>,
}

pub(crate) struct PyprojectTomlManifestProvider;

impl ManifestProvider for PyprojectTomlManifestProvider {
    fn name(&self) -> ManifestName {
        SharedString::new_static("pyproject.toml").into()

View on GitHub (pinned to f4178619ac)

Solutions

1. Verify the python asset is present in the grammars crate's embedded file list and rebuild
2. Add a test asserting get_file succeeds for every language's rules file
3. Return default empty rules with a warning instead of panicking

When it happens

Trigger: Thrown at crates/languages/src/python.rs:57 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of zed-industries/zed@f4178619ac (2026-08-20). Data as JSON: /api/errors/0749206ada9e048a. Report an issue: GitHub.