tvl-depot/tvix/eval
Griffin Smith 67e796b2e1 test(tvix/eval): Add the start of a nix oracle test suite
Add the start of a test suite that compares tvix eval results against
nix, using the string repr of the value as the comparison. This shells
out to a nix-instantiate binary, which is configurable as an environment
variable, to eval - there's some extra machinery there to setup a new
nix store as a tempdir to allow running this test inside the nix build
for tvix-eval itself.

Currently this has a macro that'll allow writing lots and lots of
hardcoded tests, but going forward I'm also going to be looking into
adding proptest-based generation of expressions to compare.

Change-Id: I9f4895fab1e668ed2b7dfd6f92f8c80de1bbb16b
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6307
Autosubmit: grfn <grfn@gws.fyi>
Reviewed-by: tazjin <tazjin@tvl.su>
Tested-by: BuildkiteCI
2022-09-17 17:23:55 +00:00
..
benches test(tvix/eval): Add attr merge benchmarks 2022-09-03 06:56:02 +00:00
docs docs(tvix/eval): propose builtin "inlining" optimisation 2022-09-11 20:02:46 +00:00
src feat(tvix_eval): Support builtins.compareVersions 2022-09-17 14:48:58 +00:00
tests test(tvix/eval): Add the start of a nix oracle test suite 2022-09-17 17:23:55 +00:00
.gitignore feat(tvix/eval): check in generated project skeleton 2022-08-12 12:34:29 +00:00
.skip-subtree feat(tvix/tests): check in Nix' language test suite 2022-08-24 21:25:41 +00:00
Cargo.lock test(tvix/eval): Add the start of a nix oracle test suite 2022-09-17 17:23:55 +00:00
Cargo.toml test(tvix/eval): Add the start of a nix oracle test suite 2022-09-17 17:23:55 +00:00
default.nix test(tvix/eval): Add the start of a nix oracle test suite 2022-09-17 17:23:55 +00:00
eval-okay-builtins-compareVersions.exp feat(tvix_eval): Support builtins.compareVersions 2022-09-17 14:48:58 +00:00
eval-okay-builtins-compareVersions.nix feat(tvix_eval): Support builtins.compareVersions 2022-09-17 14:48:58 +00:00
README.md docs(tvix/eval): remove the note on the private repo 2022-09-11 19:58:44 +00:00

Tvix Evaluator

This project implements an interpreter for the Nix programming language. You can experiment with an online version of the evaluator: tvixbolt.

The interpreter aims to be compatible with nixpkgs, on the foundation of Nix 2.3.

Important note: The evaluator is not yet feature-complete, and while the core mechanisms (compiler, runtime, ...) have stabilised somewhat, a lot of components are still changing rapidly.

Please contact TVL with any questions you might have.

Building the evaluator

If you are in a full checkout of the TVL depot, you can simply run mg build in this directory (or mg build //tvix/eval from anywhere in the repo).

Important note: We only use and test Nix builds of our software against Nix 2.3. There are a variety of bugs and subtle problems in newer Nix versions which we do not have the bandwidth to address, builds in newer Nix versions may or may not work.

The evaluator can also be built with standard Rust tooling (i.e. cargo build).

If you would like to clone only the evaluator and build it directly with Rust tooling, you can do:

git clone https://code.tvl.fyi/depot.git:/tvix/eval.git tvix-eval

cd tvix-eval && cargo build

Nix test suite

C++ Nix implements a language test suite in the form of Nix source code files, and their expected output. The coverage of this test suite is not complete, but we intend to be compatible with it.

We have ported the test suite to Tvix, but do not run it by default as we are not yet compatible with it.

You can run the test suite by enabling the nix_tests feature in Cargo:

cargo test --features nix_tests

rnix-parser

Tvix is written in memory of jD91mZM2, the author of rnix-parser who sadly passed away.

Tvix makes heavy use of rnix-parser in its bytecode compiler. The parser is now maintained by Nix community members.