fix: doc comments regarding safety for Number.toU32()#27
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Discovered this while working on ChainSafe/lodestar-z#349. `napi_get_value_uint32` makes no guarantee of erroring on values out of bounds: > Let int32bit be int modulo 2**32. Source: https://tc39.es/ecma262/#sec-touint32 This little code snippet PoC when added to `BeaconStateView.test.ts` in lodestar-z passes: ```ts it("toU32 silently wraps around", () => { let i = 0; for (i = 0; i < 100; i++) { const a = state.getBalance(0 + i); const b = state.getBalance(2 ** 32 + i); expect(a).toBe(b); } }); ``` While this fails, but only because we're access the SSZ list index out of bounds: ```ts state.getBalance(-1) ``` ``` FAIL bindings/test/beaconStateView.test.ts > BeaconStateView > probe truncation behavior Error: IndexOutOfBounds ``` Other conversion methods might behave the same; i haven't fully checked, but we should be careful of this
nazarhussain
approved these changes
May 5, 2026
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Discovered this while working on ChainSafe/lodestar-z#349.
napi_get_value_uint32makes no guarantee of erroring on values out of bounds:Source: https://tc39.es/ecma262/#sec-touint32
This little code snippet PoC when added to
BeaconStateView.test.tsin lodestar-z passes:While this fails, but only because we're access the SSZ list index out of bounds:
Other conversion methods might behave the same; i haven't fully checked, but we should be careful of this