expected EnvironmentVariables dictionary, got {value:?}

Error message

expected EnvironmentVariables dictionary, got {value:?}

What it means

Test assertion panic in test_render_plist. The test requires that the plist dictionary rendered by render_plist contains an 'EnvironmentVariables' key holding a dictionary in which PATH equals /usr/bin:/bin. The panic arm runs whenever the key is absent or holds a non-dictionary value, dumping the actual value with {:?}.

Source

Thrown at src/system/launchd.rs:818

                    .to_string_lossy()
                    .to_string()
            ))
        );
        match dict.get("ProgramArguments") {
            Some(Value::Array(args)) => {
                assert_eq!(args[0], Value::String("/bin/echo".to_string()));
                assert_eq!(args[1], Value::String("hello".to_string()));
            }
            value => panic!("expected ProgramArguments array, got {value:?}"),
        }
        match dict.get("EnvironmentVariables") {
            Some(Value::Dictionary(env)) => {
                assert_eq!(
                    env.get("PATH"),
                    Some(&Value::String("/usr/bin:/bin".to_string()))
                );
            }
            value => panic!("expected EnvironmentVariables dictionary, got {value:?}"),
        }
        assert!(plist_matches(&plist, &request));
    }

    #[test]
    fn test_render_plist_multiple_calendar_intervals() {
        let request = LaunchdRequest {
            name: "sync".to_string(),
            label: "dev.mise.sync".to_string(),
            program: "/bin/echo".to_string(),
            args: vec![],
            run_at_load: false,
            keep_alive: false,
            keep_alive_on_failure: false,
            start_interval: None,
            throttle_interval: None,
            nice: None,
            start_calendar_interval: Some(LaunchdCalendarIntervals::Multiple(vec![

View on GitHub (pinned to afd2eddd3a)

Solutions

Inspect the {value:?} payload in the panic to see the actual parsed plist fragment
Check render_plist in src/system/launchd.rs still serializes request.environment as an 'EnvironmentVariables' dictionary
Restore the key or update the test to match the new intended plist schema
Verify the PATH entry survives any env filtering/normalization added to render_plist

Example fix

// before
value => panic!("expected EnvironmentVariables dictionary, got {value:?}"),
// after
// ensure render_plist emits:
// "EnvironmentVariables" => Value::Dictionary(map with "PATH" => Value::String("/usr/bin:/bin"))

Defensive patterns

Strategy: validation

Validate before calling

let env = match dict.get("EnvironmentVariables") {
    Some(Value::Dictionary(e)) => e,
    other => panic!("EnvironmentVariables missing or wrong type: {other:?}"),
};
assert_eq!(env.get("PATH"), Some(&Value::String("/usr/bin:/bin".into())));

Type guard

fn as_dict(v: Option<&Value>) -> Option<&std::collections::HashMap<String, Value>> {
    match v { Some(Value::Dictionary(d)) => Some(d), _ => None }
}

Prevention

Never serialize empty env maps by omitting the key if tests expect the key present
Cover env serialization in a focused unit test on render_plist
Keep key names as constants shared between serializer and tests

When it happens

Trigger: render_plist omits 'EnvironmentVariables' from the generated launchd plist, or emits it as a non-dictionary (array/string), so the match on dict.get("EnvironmentVariables") falls through to the catch-all arm.

Common situations: Refactoring how environment variables are serialized into the plist, accidentally skipping empty env maps, or renaming the key — all cause this test to panic during cargo test.

Related errors

AI-assisted analysis of jdx/mise@afd2eddd3a (2026-09-09). Data as JSON: /api/errors/917badfcc6b96440. Report an issue: GitHub.