earendil-works/pi · error · TypeError

Eval input arrays must not be sparse.

Error message

Eval input arrays must not be sparse.

What it means

Error "Eval input arrays must not be sparse." thrown in earendil-works/pi.

Source

Thrown at packages/evals/src/vitest-evals/harness-table.ts:80

	}
	return { schemaVersion, evalSet, groupKey, harness, baseline, candidates, repetition };
}

function canonicalizeJson(value: unknown, ancestors: WeakSet<object>): JsonValue {
	if (value === null || typeof value === "string" || typeof value === "boolean") return value;
	if (typeof value === "number") {
		if (!Number.isFinite(value)) throw new TypeError("Eval input must contain only finite numbers.");
		return value;
	}
	if (typeof value !== "object") throw new TypeError("Eval input must be JSON-serializable.");
	if (ancestors.has(value)) throw new TypeError("Eval input must not contain circular references.");

	ancestors.add(value);
	try {
		if (Array.isArray(value)) {
			const result: JsonValue[] = [];
			for (let index = 0; index < value.length; index += 1) {
				if (!Object.hasOwn(value, index)) throw new TypeError("Eval input arrays must not be sparse.");
				result.push(canonicalizeJson(value[index], ancestors));
			}
			return result;
		}
		const prototype = Object.getPrototypeOf(value);
		if (prototype !== Object.prototype && prototype !== null) {
			throw new TypeError("Eval input must contain only plain objects and arrays.");
		}
		const entries: Array<[string, unknown]> = Object.entries(value);
		return Object.fromEntries(
			entries
				.sort(([left], [right]) => (left < right ? -1 : left > right ? 1 : 0))
				.map(([key, item]): [string, JsonValue] => [key, canonicalizeJson(item, ancestors)]),
		);
	} finally {
		ancestors.delete(value);
	}
}

View on GitHub (pinned to 4af9d21d3b)

When it happens

Trigger: Thrown at packages/evals/src/vitest-evals/harness-table.ts:80 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of earendil-works/pi@4af9d21d3b (2026-08-24). Data as JSON: /api/errors/fc2309003fa9ee8f. Report an issue: GitHub.