Humanizr/Humanizer · critical · InvalidOperationException

Locale '{localeCode}.surfaces.ordinal.dateOnly' must be a ma

Error message

Locale '{localeCode}.surfaces.ordinal.dateOnly' must be a mapping, not a scalar or sequence.

What it means

Thrown by AddOrdinalFeatures when surfaces.ordinal.dateOnly is present but is not a YAML mapping. The 'dateOnly' surface (dateOnlyToOrdinalWords) must be a mapping; scalar or sequence values are rejected at build time.

Source

Thrown at src/Humanizer.SourceGenerators/Common/CanonicalLocaleAuthoring.cs:438

                features["ordinalizer"] = numericMapping;
            }

            if (ordinalSurface.TryGetValue("date", out var dateValue))
            {
                if (dateValue is not SimpleYamlMapping dateMapping)
                {
                    throw new InvalidOperationException(
                        $"Locale '{localeCode}.surfaces.ordinal.date' must be a mapping, not a scalar or sequence.");
                }

                features["dateToOrdinalWords"] = dateMapping;
            }

            if (ordinalSurface.TryGetValue("dateOnly", out var dateOnlyValue))
            {
                if (dateOnlyValue is not SimpleYamlMapping dateOnlyMapping)
                {
                    throw new InvalidOperationException(
                        $"Locale '{localeCode}.surfaces.ordinal.dateOnly' must be a mapping, not a scalar or sequence.");
                }

                features["dateOnlyToOrdinalWords"] = dateOnlyMapping;
            }
        }

        static void AddCalendarFeatures(
            string localeCode,
            SimpleYamlMapping calendarSurface,
            ImmutableDictionary<string, SimpleYamlValue>.Builder features)
        {
            foreach (var property in calendarSurface.Values.Keys.Where(static property => property is not ("months" or "monthsGenitive" or "hijriMonths")))
            {
                throw new InvalidOperationException(
                    $"Locale '{localeCode}.surfaces.calendar' defines unsupported property '{property}'. Supported properties: months, monthsGenitive, hijriMonths.");
            }

View on GitHub (pinned to ffc2b77c0f)

Solutions

1. Rewrite surfaces.ordinal.dateOnly as a mapping matching the dateOnlyToOrdinalWords rule shape.
2. Mirror the structure of surfaces.ordinal.date from a reference locale and adjust for date-only semantics.
3. Rebuild to confirm the ordinal surface validates.

Example fix

# before
ordinal:
  dateOnly: true
# after
ordinal:
  dateOnly:
    1: first

# Ensure surfaces.ordinal.dateOnly is a mapping, not a scalar/sequence.
# YAML lint: 'dateOnly:' must be followed by an indented mapping block.

When it happens

Trigger: A locale YAML writes 'dateOnly: true' or a list under surfaces.ordinal.dateOnly. The type guard at CanonicalLocaleAuthoring.cs:436-440 fails because dateOnlyValue is not a SimpleYamlMapping.

Common situations: Confusing dateOnly with a boolean enable flag; pasting an array; mis-indentation turning the mapping into a scalar.

Related errors

• Locale '{localeCode}.surfaces.ordinal' defines unsupported p
• Locale '{localeCode}.surfaces.ordinal.numeric' must be a map
• Locale '{localeCode}.surfaces.ordinal.date' must be a mappin
• Locale '{localeCode}.{path}' defines duplicate numeric minut
• Locale '{localeCode}.{path}.{key}' must be a string.

AI-assisted analysis of Humanizr/Humanizer@ffc2b77c0f (2026-08-13). Data as JSON: /api/errors/d9d86b03f6ddb7ae. Report an issue: GitHub.