The runner of the Shuffling test type has only one handler: core
.
However, this does not mean that testing is limited. Clients may take different approaches to shuffling, for optimizing, and supporting advanced lookup behavior back in older history.
For implementers, possible test runners implementing testing can include:
- Just test permute-index, run it for each index
i
inrange(count)
, and check against expectedmapping[i]
(default spec implementation). - Test un-permute-index (the reverse lookup; implemented by running the shuffling rounds in reverse, from
round_count-1
to0
). - Test the optimized complete shuffle, where all indices are shuffled at once; test output in one go.
- Test complete shuffle in reverse (reverse rounds, same as #2).
seed: bytes32
count: int
mapping: List[int]
- The
bytes32
is encoded as a string, hexadecimal encoding, prefixed with0x
. - Integers are validator indices. These are
uint64
, but realistically they are not as big.
The count
specifies the validator registry size. One should compute the shuffling for indices 0, 1, 2, 3, ..., count (exclusive)
.
The seed
is the raw shuffling seed, passed to permute-index (or optimized shuffling approach).
The mapping
is a look up array, constructed as [spec.compute_shuffled_index(i, count, seed) for i in range(count)]
I.e. mapping[i]
is the shuffled location of i
.
The resulting list should match the expected output after shuffling the implied input, using the given seed
.
The output is checked using the mapping
, based on the shuffling test type (e.g. can be backwards shuffling).