Tests

cabal test

Suite

• The specification vectors, the step, the seeding function, blocks, derived keys and seed whitening.
• Fills, scalar draws and fills cut into slices against the stream dumps in tests/data, at K = 8 and K = 32, and genWord8 against the byte dump. Random access at chunk lengths 1 to 65536 against the definition.
• The conformance files of the spec, byte copies in tests/conformance, read by tests/Conformance.hs and run by tests/Checklist.hs, which demonstrates every item of the spec's conformance/CHECKLIST.md at 2a4bd08 that the port offers. Every case of the bounded, normal, exponential and weighted choice files runs as a fill, as scalar draws and cut at elements 1, 7, 20, 21 and n - 1, bit for bit with its end position. The checks cover the choice tables, the global draw index of the fallback, the width from the range, empty fills, the pair rule and odd n of the Float normals, rejected weights, the choice law, random access and the position bounds. The SHA-256 of every stream and dump in hashes.json matches, from the key. The port has no Bool, 128-bit, binary16, Char or complex draws, so those streams and the complex block span are left out, and the fill-end check of section 5 cannot be reached with a vector that fits in memory.
• The three Double normal dumps of hashes.json come out equal from the C fill, from scalar draws, and from Haskell fills of 1000 elements.
• Bounded and Double normal fills cut at any element, across the switch between Haskell and C and across the pieces of a long C fill. Empty fills, position rules of draws, split, fork and purpose, constructor bounds.
• Four raw moments and the Kolmogorov-Smirnov distance of 10^7 normals and exponentials, in Double and Float.
• RandomGen and SplitGen against the draws, and the random stateful adapters.

Fixtures

tools/gen_fixtures.py converts the specification's vectors.json into tests/Fixtures.hs. tests/conformance/*.json are byte copies of tandem-spec 2a4bd08 conformance/*.json. tools/gen_zig_tables.py writes the ziggurat tables from the spec's JSON. cabal run -f tools tandem-dump -- normals writes the bytes of tandem-c's tools/dump_normals.c, with SHA-256 700ec4d2f4d6b82aaa56c6eff18a4e5919585fdbd093988773383d580ea610d1.

CI

CI checks the vendored C, the dumps, the fixtures, the conformance files and the ziggurat tables against the commits pinned in .github/workflows/ci.yml. The tests run with GHC 9.14 on Ubuntu and macOS and with GHC 9.12 on Ubuntu. CI also checks that the dumps hash as tandem-c's, that fused multiply-adds lower to instructions, the tests with -mfma, and the tests in pure Haskell with -f -cbits. A second job runs the tests with GHC 9.14 and -f llvm on LLVM 21, on Ubuntu and macOS.