colinhacks/zod · error · Error

Cannot create literal schema with no valid values

Error message

Cannot create literal schema with no valid values

What it means

Thrown by the $ZodLiteral constructor when def.values.length === 0. A literal schema must enumerate at least one concrete value to match against; an empty literal set has nothing to accept and would silently reject every input, so construction fails. The public z.literal() API normally guarantees a non-empty array, so this typically surfaces through direct internal construction, a buggy wrapper, or an empty spread.

Solutions

1. Ensure the values array passed to z.literal() contains at least one entry.
2. Guard dynamic generators: if (values.length === 0) throw or fall back to z.never()/z.unknown().
3. Validate configuration upstream so empty allow-lists are caught with a clearer error.
4. Unit-test the generator against an empty input.

Example fix

// before
const L = z.literal([...allowed]); // allowed is []
// after
const L = allowed.length
  ? z.literal([...allowed])
  : z.never();

function safeLiteral(values: util.Literal[]) {
  if (!Array.isArray(values) || values.length === 0) {
    return z.never();
  }
  return z.literal(values);
}

function hasValues(values: unknown): values is [unknown, ...unknown[]] {
  return Array.isArray(values) && values.length > 0;
}

When it happens

Trigger: Calling z.literal([]) or constructing $ZodLiteral with { values: [] }; spreading an empty array into z.literal(...[]); dynamically building a literal from a list that turned out empty; a custom helper that forwards user input to def.values without checking length.

Common situations: Generating literal schemas from configuration data (an empty allow-list at config time); refactoring enums to literals and forgetting a fallback; user-driven feature flags that produce no values; off-by-one filters that strip every element.

Related errors

• A discriminator value for key
• Invalid discriminated union option at index
• Invalid UUID version
• This schema contains multiple valid literal values. Use…
• Unrecognized hash format

AI-assisted analysis of colinhacks/zod@2d90846af9 (2026-08-11). Data as JSON: /api/errors/759c2140359c9e92. Report an issue: GitHub.

Appendix: source

Thrown at packages/zod/src/v4/core/schemas.ts:3296

}

export interface $ZodLiteralInternals<T extends util.Literal = util.Literal> extends $ZodTypeInternals<T, T> {
  def: $ZodLiteralDef<T>;
  values: Set<T>;
  pattern: RegExp;
  isst: errors.$ZodIssueInvalidValue;
}

export interface $ZodLiteral<T extends util.Literal = util.Literal> extends $ZodType {
  _zod: $ZodLiteralInternals<T>;
}

export const $ZodLiteral: core.$constructor<$ZodLiteral> = /*@__PURE__*/ core.$constructor(
  "$ZodLiteral",
  (inst, def) => {
    $ZodType.init(inst, def);
    if (def.values.length === 0) {
      throw new Error("Cannot create literal schema with no valid values");
    }

    const values = new Set<util.Literal>(def.values);
    inst._zod.values = values;
    inst._zod.pattern = new RegExp(
      `^(${def.values

        .map((o) => (typeof o === "string" ? util.escapeRegex(o) : o ? util.escapeRegex(o.toString()) : String(o)))
        .join("|")})$`
    );

    inst._zod.parse = (payload, _ctx) => {
      const input = payload.value;
      if (values.has(input)) {
        return payload;
      }
      payload.issues.push({
        code: "invalid_value",

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