diff options
Diffstat (limited to 'tvix/eval/src/lib.rs')
| -rw-r--r-- | tvix/eval/src/lib.rs | 151 |
1 files changed, 114 insertions, 37 deletions
diff --git a/tvix/eval/src/lib.rs b/tvix/eval/src/lib.rs index 00dc7918d41f..a53a2a02d140 100644 --- a/tvix/eval/src/lib.rs +++ b/tvix/eval/src/lib.rs @@ -42,13 +42,12 @@ use std::rc::Rc; use std::str::FromStr; use std::sync::Arc; -use crate::compiler::GlobalsMap; use crate::observer::{CompilerObserver, RuntimeObserver}; use crate::value::Lambda; use crate::vm::run_lambda; // Re-export the public interface used by other crates. -pub use crate::compiler::{compile, prepare_globals, CompilationOutput}; +pub use crate::compiler::{compile, prepare_globals, CompilationOutput, GlobalsMap}; pub use crate::errors::{AddContext, CatchableErrorKind, Error, ErrorKind, EvalResult}; pub use crate::io::{DummyIO, EvalIO, FileType}; pub use crate::pretty_ast::pretty_print_expr; @@ -64,6 +63,16 @@ pub use crate::value::{Builtin, CoercionKind, NixAttrs, NixList, NixString, Valu #[cfg(feature = "impure")] pub use crate::io::StdIO; +struct BuilderBuiltins { + builtins: Vec<(&'static str, Value)>, + src_builtins: Vec<(&'static str, &'static str)>, +} + +enum BuilderGlobals { + Builtins(BuilderBuiltins), + Globals(Rc<GlobalsMap>), +} + /// Builder for building an [`Evaluation`]. /// /// Construct an [`EvaluationBuilder`] by calling one of: @@ -75,9 +84,8 @@ pub use crate::io::StdIO; /// Then configure the fields by calling the various methods on [`EvaluationBuilder`], and finally /// call [`build`](Self::build) to construct an [`Evaluation`] pub struct EvaluationBuilder<'co, 'ro, 'env, IO> { - source_map: SourceCode, - builtins: Vec<(&'static str, Value)>, - src_builtins: Vec<(&'static str, &'static str)>, + source_map: Option<SourceCode>, + globals: BuilderGlobals, env: Option<&'env HashMap<SmolStr, Value>>, io_handle: IO, enable_import: bool, @@ -98,21 +106,31 @@ where /// - Adds a `"storeDir"` builtin containing the store directory of the configured IO handle /// - Sets up globals based on the configured builtins /// - Copies all other configured fields to the [`Evaluation`] - pub fn build(mut self) -> Evaluation<'co, 'ro, 'env, IO> { - // Insert a storeDir builtin *iff* a store directory is present. - if let Some(store_dir) = self.io_handle.as_ref().store_dir() { - self.builtins.push(("storeDir", store_dir.into())); - } + pub fn build(self) -> Evaluation<'co, 'ro, 'env, IO> { + let source_map = self.source_map.unwrap_or_default(); + + let globals = match self.globals { + BuilderGlobals::Globals(globals) => globals, + BuilderGlobals::Builtins(BuilderBuiltins { + mut builtins, + src_builtins, + }) => { + // Insert a storeDir builtin *iff* a store directory is present. + if let Some(store_dir) = self.io_handle.as_ref().store_dir() { + builtins.push(("storeDir", store_dir.into())); + } - let globals = crate::compiler::prepare_globals( - self.builtins, - self.src_builtins, - self.source_map.clone(), - self.enable_import, - ); + crate::compiler::prepare_globals( + builtins, + src_builtins, + source_map.clone(), + self.enable_import, + ) + } + }; Evaluation { - source_map: self.source_map, + source_map, globals, env: self.env, io_handle: self.io_handle, @@ -132,11 +150,13 @@ impl<'co, 'ro, 'env, IO> EvaluationBuilder<'co, 'ro, 'env, IO> { builtins.extend(builtins::placeholders()); // these are temporary Self { - source_map: SourceCode::default(), + source_map: None, enable_import: false, io_handle, - builtins, - src_builtins: vec![], + globals: BuilderGlobals::Builtins(BuilderBuiltins { + builtins, + src_builtins: vec![], + }), env: None, strict: false, nix_path: None, @@ -149,8 +169,7 @@ impl<'co, 'ro, 'env, IO> EvaluationBuilder<'co, 'ro, 'env, IO> { EvaluationBuilder { io_handle, source_map: self.source_map, - builtins: self.builtins, - src_builtins: self.src_builtins, + globals: self.globals, env: self.env, enable_import: self.enable_import, strict: self.strict, @@ -175,14 +194,64 @@ impl<'co, 'ro, 'env, IO> EvaluationBuilder<'co, 'ro, 'env, IO> { self.with_enable_import(true) } + fn builtins_mut(&mut self) -> &mut BuilderBuiltins { + match &mut self.globals { + BuilderGlobals::Builtins(builtins) => builtins, + BuilderGlobals::Globals(_) => { + panic!("Cannot modify builtins on an EvaluationBuilder with globals configured") + } + } + } + + /// Add additional builtins (represented as tuples of name and [`Value`]) to this evaluation + /// builder. + /// + /// # Panics + /// + /// Panics if this evaluation builder has had globals set via [`with_globals`] pub fn add_builtins<I>(mut self, builtins: I) -> Self where I: IntoIterator<Item = (&'static str, Value)>, { - self.builtins.extend(builtins); + self.builtins_mut().builtins.extend(builtins); + self + } + + /// Add additional builtins that are implemented in Nix source code (represented as tuples of + /// name and nix source) to this evaluation builder. + /// + /// # Panics + /// + /// Panics if this evaluation builder has had globals set via [`with_globals`] + pub fn add_src_builtin(mut self, name: &'static str, src: &'static str) -> Self { + self.builtins_mut().src_builtins.push((name, src)); self } + /// Set the globals for this evaluation builder to a previously-constructed globals map. + /// Intended to allow sharing globals across multiple evaluations (eg for the REPL). + /// + /// Discards any builtins previously configured via [`add_builtins`] and [`add_src_builtins`]. + /// If either of those methods is called on the evaluation builder after this one, they will + /// panic. + pub fn with_globals(self, globals: Rc<GlobalsMap>) -> Self { + Self { + globals: BuilderGlobals::Globals(globals), + ..self + } + } + + pub fn with_source_map(self, source_map: SourceCode) -> Self { + debug_assert!( + self.source_map.is_none(), + "Cannot set the source_map on an EvaluationBuilder twice" + ); + Self { + source_map: Some(source_map), + ..self + } + } + pub fn with_strict(self, strict: bool) -> Self { Self { strict, ..self } } @@ -191,11 +260,6 @@ impl<'co, 'ro, 'env, IO> EvaluationBuilder<'co, 'ro, 'env, IO> { self.with_strict(true) } - pub fn add_src_builtin(mut self, name: &'static str, src: &'static str) -> Self { - self.src_builtins.push((name, src)); - self - } - pub fn nix_path(self, nix_path: Option<String>) -> Self { Self { nix_path, ..self } } @@ -234,8 +298,8 @@ impl<'co, 'ro, 'env, IO> EvaluationBuilder<'co, 'ro, 'env, IO> { } impl<'co, 'ro, 'env, IO> EvaluationBuilder<'co, 'ro, 'env, IO> { - pub fn source_map(&self) -> &SourceCode { - &self.source_map + pub fn source_map(&mut self) -> &SourceCode { + self.source_map.get_or_insert_with(SourceCode::default) } } @@ -255,7 +319,9 @@ impl<'co, 'ro, 'env> EvaluationBuilder<'co, 'ro, 'env, Box<dyn EvalIO>> { pub fn enable_impure(mut self, io: Option<Box<dyn EvalIO>>) -> Self { self.io_handle = io.unwrap_or_else(|| Box::new(StdIO) as Box<dyn EvalIO>); self.enable_import = true; - self.builtins.extend(builtins::impure_builtins()); + self.builtins_mut() + .builtins + .extend(builtins::impure_builtins()); // Make `NIX_PATH` resolutions work by default, unless the // user already overrode this with something else. @@ -332,9 +398,26 @@ pub struct EvaluationResult { } impl<'co, 'ro, 'env, IO> Evaluation<'co, 'ro, 'env, IO> { + /// Make a new [builder][] for configuring an evaluation + /// + /// [builder]: EvaluationBuilder pub fn builder(io_handle: IO) -> EvaluationBuilder<'co, 'ro, 'env, IO> { EvaluationBuilder::new(io_handle) } + + /// Clone the reference to the map of Nix globals for this evaluation. If [`Value`]s are shared + /// across subsequent [`Evaluation`]s, it is important that those evaluations all have the same + /// underlying globals map. + pub fn globals(&self) -> Rc<GlobalsMap> { + self.globals.clone() + } + + /// Clone the reference to the contained source code map. This is used after an evaluation for + /// pretty error printing. Also, if [`Value`]s are shared across subsequent [`Evaluation`]s, it + /// is important that those evaluations all have the same underlying source code map. + pub fn source_map(&self) -> SourceCode { + self.source_map.clone() + } } impl<'co, 'ro, 'env> Evaluation<'co, 'ro, 'env, Box<dyn EvalIO>> { @@ -352,12 +435,6 @@ impl<'co, 'ro, 'env, IO> Evaluation<'co, 'ro, 'env, IO> where IO: AsRef<dyn EvalIO> + 'static, { - /// Clone the reference to the contained source code map. This is used after - /// an evaluation for pretty error printing. - pub fn source_map(&self) -> SourceCode { - self.source_map.clone() - } - /// Only compile the provided source code, at an optional location of the /// source code (i.e. path to the file it was read from; used for error /// reporting, and for resolving relative paths in impure functions) |