diff options
author | Vincent Ambo <mail@tazj.in> | 2022-08-24T13·58+0300 |
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committer | tazjin <tazjin@tvl.su> | 2022-09-02T12·59+0000 |
commit | 3d0280ec03f927ae4925aae400600a7b96058587 (patch) | |
tree | 93dc6dc23bb5fce5655f27cb563a984d3b11eda2 /tvix/eval/src/builtins | |
parent | 07fcaf034b17df80de2f37de008562209a76987c (diff) |
refactor(tvix/eval): implement clearer mechanism for globals r/4592
The set of things that can leak out of `builtins` into the global scope is statically known (it is what Nix 2.3 leaks there, essentially). This is a mild change over the previous mechanism, where instead at the point where the `builtins` set is constructed we "lift" the globals out of there (if they exist). This way users will still eventually be able to add additional builtins, HOWEVER they will not be able to leak them into the global scope. Note that upstream Nix technically leaks _all_ builtins into the global scope using the `__*` prefix, but we are trying to avoid this in Tvix if it is not required in nixpkgs. Change-Id: Ie9dec2ce33740134f3b2464eba3749f421dd5953 Reviewed-on: https://cl.tvl.fyi/c/depot/+/6258 Tested-by: BuildkiteCI Reviewed-by: sterni <sternenseemann@systemli.org>
Diffstat (limited to 'tvix/eval/src/builtins')
-rw-r--r-- | tvix/eval/src/builtins/mod.rs | 67 |
1 files changed, 52 insertions, 15 deletions
diff --git a/tvix/eval/src/builtins/mod.rs b/tvix/eval/src/builtins/mod.rs index b5e8bb289b0e..39e29580b4c3 100644 --- a/tvix/eval/src/builtins/mod.rs +++ b/tvix/eval/src/builtins/mod.rs @@ -3,29 +3,66 @@ //! See //tvix/eval/docs/builtins.md for a some context on the //! available builtins in Nix. -use std::collections::HashMap; +use std::{ + collections::{BTreeMap, HashMap}, + rc::Rc, +}; -use crate::value::{Builtin, Value}; +use crate::value::{Builtin, NixAttrs, NixString, Value}; -macro_rules! builtin { - ( $map:ident, $name:literal, $arity:literal, $body:expr ) => { - $map.insert($name, Value::Builtin(Builtin::new($name, $arity, $body))); - }; +fn pure_builtins() -> Vec<Builtin> { + vec![ + Builtin::new("isNull", 1, |args| { + Ok(Value::Bool(matches!(args[0], Value::Null))) + }), + Builtin::new("toString", 1, |args| { + // TODO: toString is actually not the same as Display + Ok(Value::String(format!("{}", args[0]).into())) + }), + ] +} + +fn builtins_set() -> NixAttrs { + let mut map: BTreeMap<NixString, Value> = BTreeMap::new(); + + for builtin in pure_builtins() { + map.insert(builtin.name().into(), Value::Builtin(builtin)); + } + + NixAttrs::from_map(map) } /// Set of Nix builtins that are globally available. pub fn global_builtins() -> HashMap<&'static str, Value> { - let mut globals = HashMap::new(); + let builtins = builtins_set(); + let mut globals: HashMap<&'static str, Value> = HashMap::new(); - builtin!(globals, "isNull", 1, |args| Ok(Value::Bool(matches!( - args[0], - Value::Null - )))); + // known global builtins from the builtins set. + for global in &[ + "abort", + "baseNameOf", + "derivation", + "derivationStrict", + "dirOf", + "fetchGit", + "fetchMercurial", + "fetchTarball", + "fromTOML", + "import", + "isNull", + "map", + "placeholder", + "removeAttrs", + "scopedImport", + "throw", + "toString", + ] { + if let Some(builtin) = builtins.select(global) { + globals.insert(global, builtin.clone()); + } + } - builtin!(globals, "toString", 1, |args| { - // TODO: toString is actually not the same as Display - Ok(Value::String(format!("{}", args[0]).into())) - }); + globals.insert("builtins", Value::Attrs(Rc::new(builtins))); globals } |