apple/pkl · error · PklException

Invalid DataSize unit symbol:

Error message

Invalid DataSize unit symbol: 

What it means

PklException("Invalid DataSize unit symbol: " + symbol) is thrown by DependencyMetadata.parsePObject when the `unit` field of a DataSize value is not a recognized DataSizeUnit symbol (e.g. "b", "kb", "mb", "gb", "tb"...). An unrecognized symbol means the metadata cannot construct a DataSize. It indicates a typo or wrong-casing in the unit symbol.

Source

Thrown at pkl-core/src/main/java/org/pkl/core/packages/DependencyMetadata.java:250

          var properties = new HashMap<String, Object>();
          for (var kv : props.entrySet()) {
            properties.put(kv.getKey(), parsePObject(kv.getValue()));
          }
          return new PObject(classInfo, properties);
        }
        case "Pattern" -> {
          var value = jsObj.getString("value");
          return Pattern.compile(value);
        }
        case "DataSize" -> {
          var symbol = jsObj.getString("unit");
          var value = jsObj.get("value");
          if (value == null) {
            throw new MissingFieldException(jsObj, "value");
          }
          var unit = DataSizeUnit.parse(symbol);
          if (unit == null) {
            throw new PklException("Invalid DataSize unit symbol: " + symbol);
          }
          if (!(value instanceof Double num)) {
            throw new FormatException("double", value.getClass());
          }
          return new DataSize(num, unit);
        }
        case "Duration" -> {
          var symbol = jsObj.getString("unit");
          var value = jsObj.get("value");
          if (value == null) {
            throw new MissingFieldException(jsObj, "value");
          }
          var unit = DurationUnit.parse(symbol);
          if (unit == null) {
            throw new PklException("Invalid Duration unit symbol: " + symbol);
          }
          if (!(value instanceof Double num)) {
            throw new FormatException("double", value.getClass());

View on GitHub (pinned to f3efcbfc9b)

Solutions

1. Use a valid Pkl DataSize unit symbol with correct casing, e.g. "kb", "mb", "gb" (or binary variants like "kib", "mib").
2. Regenerate the metadata with `pkl project package` so units are serialized canonically.
3. Check DataSizeUnit.parse for the exact accepted symbol list and match it.
4. Fall back to the base unit (e.g. convert to "b" bytes) if unsure.

Example fix

// before
{"type": "DataSize", "unit": "MB", "value": 10.0}
// after
{"type": "DataSize", "unit": "mb", "value": 10.0}

var validUnits = java.util.Set.of("b","kb","mb","gb","tb","pb","kib","mib","gib","tib","pib");
var unit = entry.get("unit").asString();
if (!validUnits.contains(unit)) throw new IllegalStateException("Unknown DataSize unit symbol: " + unit);

When it happens

Trigger: Parsing metadata with a DataSize entry whose `unit` is an unknown string such as "MB", "megabytes", "kib", or an empty string.

Common situations: Hand-written annotations using human unit names; case-sensitivity mistakes ("MB" vs "mb"); confusion between binary unit families supported by Pkl's DataSizeUnit.

Understand the failure class

Background: Invalid enum value errors: "Unknown type", "Invalid scope", "must be one of" — when a string is not on the library's allowed list — this error's family across 23 libraries.

Related errors

• value
• double
• object
• array
• Could not read annotation. Invalid object:

AI-assisted analysis of apple/pkl@f3efcbfc9b (2026-09-08). Data as JSON: /api/errors/0e6bfd7611907589. Report an issue: GitHub.