# `Encoding` Invariants## `testRoundTripAToB` never fails.**Test:**[`FuzzEncoding.sol#L56`](../contracts/echidna/FuzzEncoding.sol#L56)Asserts that a raw versioned nonce can be encoded / decoded to reach the same raw value. ## `testRoundTripBToA` never fails.**Test:**[`FuzzEncoding.sol#L67`](../contracts/echidna/FuzzEncoding.sol#L67)Asserts that an encoded versioned nonce can always be decoded / re-encoded to reach the same encoded value.