jdx/mise · error · eyre::Report

invalid Cargo crate name: {name:?}

Error message

invalid Cargo crate name: {name:?}

What it means

get_crate_url() builds the crates.io sparse-index URL for a crate name so mise can list its versions. A crates.io index path can only be constructed from a non-empty, pure-ASCII name, so anything else (empty string or any non-ASCII character) is rejected with this bail before a URL is formed.

Source

Thrown at src/backend/cargo.rs:522

        } else if let Some((user, repo)) = self.tool_name().split_once('/') {
            format!("https://github.com/{user}/{repo}.git").parse().ok()
        } else {
            None
        }
    }
}

fn format_tool_options(options: &[&'static str]) -> String {
    options
        .iter()
        .map(|option| format!("`{option}`"))
        .collect::<Vec<_>>()
        .join(", ")
}

fn get_crate_url(name: &str) -> eyre::Result<Url> {
    if name.is_empty() || !name.is_ascii() {
        bail!("invalid Cargo crate name: {name:?}");
    }
    let name = name.to_lowercase();
    let url = match name.len() {
        1 => format!("https://index.crates.io/1/{name}"),
        2 => format!("https://index.crates.io/2/{name}"),
        3 => format!("https://index.crates.io/3/{}/{name}", &name[..1]),
        _ => format!(
            "https://index.crates.io/{}/{}/{name}",
            &name[..2],
            &name[2..4]
        ),
    };
    Ok(url.parse()?)
}

fn parse_crate_versions(response: &str) -> eyre::Result<Vec<VersionInfo>> {
    let mut versions = vec![];
    for version in Deserializer::from_str(response).into_iter::<CrateVersion>() {

View on GitHub (pinned to 6f52dcdf99)

Solutions

1. Fix the crate name in mise.toml / CLI argument to the exact ASCII spelling from crates.io
2. Check for invisible unicode characters (homoglyphs, NBSP) with a hex dump of the config line
3. If generating config programmatically, validate the name is non-empty ASCII before writing it

Example fix

# before
mise use "cargo:cargô"
# after
mise use cargo:cargo

# shell: reject empty/non-ASCII crate names before calling mise
name='bat'
[[ "$name" =~ ^[A-Za-z0-9_-]+$ ]] && [[ -n "$name" ]] || { echo 'bad crate name'; exit 1; }

When it happens

Trigger: `mise use cargo:<name>` / a mise.toml entry `"cargo:<name>"` where <name> is empty or contains non-ASCII characters (e.g. a typo, a unicode look-alike character, or programmatic construction of a ToolRequest with a bad name). Fails during version listing or install when get_crate_url is called.

Common situations: Copy-pasting a crate name with a homoglyph or trailing unicode whitespace; an empty name from a templating/scripting bug in generated config; refactoring tool ids that accidentally drops the crate name after `cargo:`.

Related errors

• cargo-binstall cannot honor cargo install-only tool option(s
• windows_script_interpreter: {interpreter:?} must be a plain
• Windows script file name {filename:?} contains unsupported c
• workspace provider {provider_id:?} returned duplicate projec
• Cargo workspace member pattern {member:?} must be relative

AI-assisted analysis of jdx/mise@6f52dcdf99 (2026-08-22). Data as JSON: /api/errors/d4d218878069d2e1. Report an issue: GitHub.