d9d627cdf0
This relates to the (abandoned) cl/7256. Introduces a Cargo workspace at //tvix that is primarily intended to be used as a workaround for the annoying Nix+Rust tooling while having a consistent set of dependencies. This is driven in part by a desire to adopt crate2nix and get more granular Nix builds for Tvix's Rust projects, and in part by a need to split //tvix/eval into something providing the CLI (REPL etc.), and a library providing eval, without significantly altering the structure of build targets. To accomplish this the workspace has been designed to allow projects to remain independent build targets. I want to avoid lumping all the projects together - something like //tvix/eval should always be independent of other parts of tvix. A helper function in //tvix/default.nix lets downstream naersk projects construct a sparse root for the project which combines the workspace's `Cargo.lock` with the project's own `Cargo.toml`. Note that cargo commands in the workspace itself require the build dependencies of _all_ projects to be present, which is currently a bit annoying to accomplish. This introduces some breakage: 1. It breaks usage of rust-analyser without being in a shell with the dependencies of *all* Tvix projects, as it is not capable of respecting only the subset of dependencies for a part of the workspace. 2. It is no longer possible to run tests using `cargo test`, as the test generation crate we use does not work with workspaces: https://github.com/frehberg/test-generator/issues/6 This still works in the Nix build as we construct a Cargo project that looks like it's not in a workspace there. Until somebody fixes that crate / writes a new macro / does something else with the test suite, the way to run the tests is through the Nix build. Long-term we'll probably want to get rid of cargo completely, it's just a big wart and most tooling works without it if correctly configured, but we don't have time for that now. Change-Id: I846bff7a8429a25c077fd1e9ef4e3c34a299a4a1 Reviewed-on: https://cl.tvl.fyi/c/depot/+/7533 Reviewed-by: flokli <flokli@flokli.de> Autosubmit: tazjin <tazjin@tvl.su> Tested-by: BuildkiteCI |
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| benches | ||
| builtin-macros | ||
| docs | ||
| proptest-regressions/value | ||
| src | ||
| tests | ||
| .skip-subtree | ||
| build.rs | ||
| Cargo.toml | ||
| default.nix | ||
| README.md | ||
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). The mg command is found in /tools/magrathea.
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.