brew-cask:{}: {kind} terminate_process notices must be an ar

Error message

brew-cask:{}: {kind} terminate_process notices must be an array

What it means

Thrown while parsing a terminate_process step. The optional 'notices' key must be an array of strings (user-facing notes shown before the process is terminated). Supplying any non-array JSON value — a bare string, number, or object — hits the Some(_) arm and bails. (Array entries that are not strings produce the sibling 'notices must be strings' error.)

Source

Thrown at src/system/packages/brew/cask.rs:5764

                            "brew-cask:{}: {kind} terminate_process attempts must be a positive integer",
                            cask.token
                        )
                    })?,
            };
            let notices = match object.get("notices") {
                None => Vec::new(),
                Some(Value::Array(values)) => values
                    .iter()
                    .map(|value| {
                        value.as_str().map(str::to_string).ok_or_else(|| {
                            eyre!(
                                "brew-cask:{}: {kind} terminate_process notices must be strings",
                                cask.token
                            )
                        })
                    })
                    .collect::<Result<Vec<_>>>()?,
                Some(_) => bail!(
                    "brew-cask:{}: {kind} terminate_process notices must be an array",
                    cask.token
                ),
            };
            let failure_message = match object.get("failure_message") {
                None | Some(Value::Null) => None,
                Some(Value::String(value)) => Some(value.clone()),
                Some(_) => bail!(
                    "brew-cask:{}: {kind} terminate_process failure_message must be a string",
                    cask.token
                ),
            };
            Ok(FlightStep::TerminateProcess {
                name: name.to_string(),
                match_mode,
                sudo,
                attempts,
                must_succeed,

View on GitHub (pinned to 6f52dcdf99)

Solutions

Wrap notices in an array of strings: "notices": ["This will close the app"]
Omit the key entirely if there are no notices (it defaults to an empty list)

Example fix

// before
{"type": "terminate_process", "name": "x", "notices": "will restart the app"}
// after
{"type": "terminate_process", "name": "x", "notices": ["will restart the app"]}

Defensive patterns

Strategy: validation

Validate before calling

fn notices_ok(step: &serde_json::Value) -> bool {
    match step.get("notices") {
        None => true,
        Some(serde_json::Value::Array(_)) => true,
        Some(_) => false,
    }
}

Try / catch

match parse_flight_step(&cask, kind, &step) {
    Ok(step) => { /* proceed */ }
    Err(e) if e.to_string().contains("notices must be an array") => {
        eprintln!("wrap each notice in a one-element array of strings");
    }
    Err(e) => return Err(e),
}

Prevention

Always emit notices as arrays, even for a single message
Check that templating does not collapse one-element lists to scalars

When it happens

Trigger: {"type": "terminate_process", "name": "x", "notices": "closing app"} or "notices": {"text": "..."} inside a preflight/postflight step.

Common situations: Authors writing a single notice as a plain string instead of a one-element array; config templating that renders a scalar when the list has one item.

Related errors

AI-assisted analysis of jdx/mise@6f52dcdf99 (2026-08-22). Data as JSON: /api/errors/895a6e4210101183. Report an issue: GitHub.