junit-team/junit5 · warning · DateTimeParseException

Timeout duration is not in the expected format (<number> [ns

Error message

Timeout duration is not in the expected format (<number> [ns|μs|ms|s|m|h|d])

What it means

Thrown by TimeoutDurationParser.parse() when the supplied text does not match the expected pattern '([1-9]\d*) ?((?:[nμm]?s)|m|h|d)?' (case-insensitive, unicode-aware). The format is a positive integer optionally followed by a unit abbreviation (ns, μs, ms, s, m, h, d); seconds is the default when no unit is given. Note: when used via TimeoutConfiguration for config parameters, this exception is caught and logged as a warning with the timeout ignored, so it does not surface as a test failure in that path.

Source

Thrown at junit-jupiter-engine/src/main/java/org/junit/jupiter/engine/extension/TimeoutDurationParser.java:58

		"ns", NANOSECONDS, //
		"μs", MICROSECONDS, //
		"ms", MILLISECONDS, //
		"s", SECONDS, //
		"m", MINUTES, //
		"h", HOURS, //
		"d", DAYS //
	);

	TimeoutDuration parse(CharSequence text) throws DateTimeParseException {
		Matcher matcher = PATTERN.matcher(text);
		if (matcher.matches()) {
			long value = Long.parseLong(matcher.group(1));
			String unitAbbreviation = matcher.group(2);
			TimeUnit unit = unitAbbreviation == null ? SECONDS
					: requireNonNull(UNITS_BY_ABBREVIATION.get(unitAbbreviation.toLowerCase(Locale.ENGLISH)));
			return new TimeoutDuration(value, unit);
		}
		throw new DateTimeParseException("Timeout duration is not in the expected format (<number> [ns|μs|ms|s|m|h|d])",
			text, 0);
	}

}

View on GitHub (pinned to 956246301e)

Solutions

1. Use one of the supported unit abbreviations: ns, μs, ms, s, m, h, d — e.g., '500ms' not '500millis'
2. Ensure the value is a positive integer (regex requires [1-9]\d*), so '0' and decimals are invalid
3. Check the log output for the 'Ignored invalid timeout' warning to confirm the parser rejected your value
4. Omit the unit entirely to default to seconds (e.g., '30' means 30 seconds)

Example fix

# before (in junit-platform.properties)
junit.jupiter.execution.timeout.default = 500millis

# after
junit.jupiter.execution.timeout.default = 500ms

// Validate a timeout config string before relying on it
String timeout = "500ms";
Pattern p = Pattern.compile("([1-9]\\d*) ?((?:[nμm]?s)|m|h|d)?",
    Pattern.CASE_INSENSITIVE | Pattern.UNICODE_CASE);
if (!p.matcher(timeout).matches()) {
    throw new IllegalArgumentException(
        "Invalid timeout format: " + timeout + ". Expected: <number> [ns|μs|ms|s|m|h|d]");
}
Set<String> validUnits = Set.of("ns", "μs", "ms", "s", "m", "h", "d");

When it happens

Trigger: Calling TimeoutDurationParser.parse(CharSequence) with a string that fails the regex: zero ('0s'), negative ('-5s'), decimal ('1.5s'), unsupported unit ('5min'), trailing characters ('5 seconds'), or a value starting with 0. This is invoked when parsing junit.jupiter.execution.timeout.* configuration parameter values.

Common situations: Setting junit.jupiter.execution.timeout.testable.method or junit.jupiter.execution.timeout.default in junit-platform.properties with a typo, wrong unit abbreviation (e.g., 'min' instead of 'm', 'sec' instead of 's'), or a zero/decimal value. The value is silently ignored and a warning is logged, so timeouts silently don't apply.

Related errors

• Could not map TimeUnit <unit> to ChronoUnit
• thread mode must not be INFERRED
• Scheduled executor could not be stopped in an orderly manner
• Failed to create output directory
• The following TestInstanceFactory extensions were registered

AI-assisted analysis of junit-team/junit5@956246301e (2026-08-04). Data as JSON: /data/errors/42324cf4e227631a.json. Report an issue: GitHub.