clockworklabs/SpacetimeDB · error · TypeError

Cannot convert to : expected bigint, integer number, or…

Error message

Cannot convert ${typeof value} to ${what}: expected bigint, integer number, or decimal string

What it means

Column-attribute validation rejects #[default(...)] on a column that also carries #[auto_inc], #[primary_key], or #[unique]. Those attributes determine the column's value authoritatively (sequence generation, key identity, uniqueness), so a user-supplied default would conflict; the error is spanned to the default expression.

Solutions

Remove #[default(...)] from the auto_inc/primary_key/unique column.
If the default genuinely matters, drop the conflicting attribute — but auto-increment ids and primary keys almost always win.
Put #[default(...)] on plain data columns instead.

Example fix

// before
#[primary_key]
#[auto_inc]
#[default(0)]
pub id: u64,

// after
#[primary_key]
#[auto_inc]
pub id: u64,

Defensive patterns

Strategy: validation

Prevention

Never combine #[default(...)] with #[auto_inc], #[primary_key], or #[unique] on one field.
Reserve #[default(...)] for plain data columns.
Review column attributes as a set: key/uniqueness attributes own the value; defaults must not fight them.

When it happens

Trigger: A field combining #[default(...)] with any of #[auto_inc], #[primary_key], or #[unique] — e.g. #[unique] #[default(0)] pub id: u64.

Common situations: Adding defaults for not-null convenience on id columns; habits carried over from ORMs where primary keys have defaults.

Related errors

AI-assisted analysis of clockworklabs/SpacetimeDB@6dee26c6ef (2026-08-20). Data as JSON: /api/errors/37df46eb62abb8a3. Report an issue: GitHub.

Appendix: source

Thrown at crates/bindings-typescript/src/lib/util.ts:115

}

/**
 * Coerces a value that should be a `bigint` — but may arrive as a `number`
 * or decimal string after passing through JSON — into a `bigint`.
 *
 * Every other type is rejected up front: bare `BigInt()` would silently
 * accept booleans (`true` → `1n`), arrays (`[42]` → `42n`) and empty
 * strings (`'' ` → `0n`), turning malformed payloads into valid-looking
 * ids instead of failing early.
 *
 * @param value The value to coerce
 * @param what Type name used in the error message (e.g. `'ConnectionId'`)
 */
export function coerceToBigInt(value: unknown, what: string): bigint {
  if (typeof value === 'bigint') return value;
  if (typeof value === 'number') return BigInt(value);
  if (typeof value === 'string' && value.trim() !== '') return BigInt(value);
  throw new TypeError(
    `Cannot convert ${typeof value} to ${what}: expected bigint, integer number, or decimal string`
  );
}

/**
 * Converts a string to PascalCase (UpperCamelCase).
 * @param str The string to convert
 * @returns The converted string
 */
export function toPascalCase(s: string): string {
  const str = toCamelCase(s);
  return str.charAt(0).toUpperCase() + str.slice(1);
}

/**
 * Type safe conversion from a string like "some_identifier-name" to "someIdentifierName".
 * @param str The string to convert
 * @returns The converted string

View on GitHub (pinned to 6dee26c6ef)